Article

A nation‐wide survey of neonicotinoid insecticides in agricultural land with implications for agri‐environment schemes

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Abstract

1.Neonicotinoids are the most widely used class of insecticides globally. However, the link between farming practices and the extent of contamination of soils and crops by neonicotinoid insecticides, as well as and the extent of such contamination in organic fields and ecological focus areas (EFAs) are currently unclear. 2.We measured the concentrations of five neonicotinoid insecticides (imidacloprid, clothianidin, thiamethoxam, thiacloprid, acetamiprid) in 702 soil and plant samples in 169 cultivated fields and EFAs from 62 conventional, integrated production and organic farms distributed over the entire lowland of Switzerland. 3.We detected neonicotinoids in 93% of organic soils and crops, and more than 80% of EFA soils and plants – two types of arable land supposedly free of insecticides. We also tested 16 samples of organic seeds, of which 14 were positive for neonicotinoids. 4.Finally, we calculated hazard quotients (HQs) and potentially affected fractions for 72 beneficial and 12 pest species. Under a field‐realistic scenario, we found that between 5.3 and 8.6% of above‐ground invertebrate species may be exposed to lethal concentrations of clothianidin, and 31.6 to 41.2% to sublethal concentrations, in “integrated production” and conventional fields. We also found that 1.3 to 6.8% (up to 12.5% based on HQs) of the beneficial invertebrate species may be exposed to sublethal concentrations of neonicotinoids in EFAs and organic fields. In contrast, no pest species would be exposed to lethal concentrations, even under a worst‐case scenario. 5.Synthesis and applications. Our study suggests that diffuse contamination by neonicotinoids may harm a significant fraction of non‐target beneficial species. The Use of neonicotinoids on crops may threaten biodiversity in refuge areas, while also potentially jeopardizing the practice of organic farming by impeding the biological control of pests. Based on our results, we call for a reduction in the dispersion and overuse of neonicotinoid insecticides in order to prevent any detrimental effects on biodiversity and ecosystem services associated with agroecosystems. This article is protected by copyright. All rights reserved.

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... When applied to seeds, only a small fraction of the water-soluble neonicotinoid active ingredients are taken up by plants, whilst up to 95% remain in the environment and contaminate soils and water 10 . Widespread use of neonicotinoids led to ubiquitous contaminations of soils, even in areas that are supposedly neonicotinoid free 11 . ...
... To confirm the uptake of neonicotinoids by the ants, we tested queens and workers from all colonies that lasted until the end of the experiment for thiamethoxam and its metabolite clothianidin using UHPLC-MS/ MS analysis. Abdomens from queens (24.75 ± 4.52 mg fresh mass) and pooled samples with worker abdomens (25.02 ± 0.23 mg fresh mass) were prepared using an adapted QuEChERS protocol 11 . The samples were weighed in 2 ml tubes and freeze-dried overnight in a FreeZone lyophilizer (Labconco). ...
... The pellet was re-extracted with 1.5 ml acetonitrile and the supernatants combined. The further purification was performed according to Humann-Guilleminot, et al. 11 with the centrifugations at 3200 g for 3 min. ...
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The widespread prophylactic usage of neonicotinoid insecticides has a clear impact on non-target organisms. However, the possible effects of long-term exposure on soil-dwelling organisms are still poorly understood especially for social insects with long-living queens. Here, we show that effects of chronic exposure to the neonicotinoid thiamethoxam on black garden ant colonies, Lasius niger, become visible before the second overwintering. Queens and workers differed in the residue-ratio of thiamethoxam to its metabolite clothianidin, suggesting that queens may have a superior detoxification system. Even though thia-methoxam did not affect queen mortality, neonicotinoid-exposed colonies showed a reduced number of workers and larvae indicating a trade-off between detoxification and fertility. Since colony size is a key for fitness, our data suggest long-term impacts of neonicotinoids on these organisms. This should be accounted for in future environmental and ecological risk assessments of neonicotinoid applications to prevent irreparable damages to ecosystems.
... People may be exposed to NEOs through several principal routes, which include ingestion, inhalation and dermal contact of pesticide-contaminated soil (Bhandari et al. 2020). NEOs have been detected in agricultural soil, industrial soil, particulate matter (PM)2.5, dust and even soil particles of residential areas (Humann-Guilleminot et al. 2019;Wang et al. 2019;Zhang et al. 2020;Zhou et al. 2020Zhou et al. , 2021. Moreover, they have been found in human urine, blood, breast milk, saliva, tooth and hair samples (Bonmatin et al. 2021;Chen et al. 2020aChen et al. , b, 2021Xu et al. 2021b;Zhang et al. 2021aZhang et al. , 2021bZhang and Lu 2022). ...
... Several publications have described the ubiquitous existence of NEOs in soils of different land use types, soil depth, seasons or regions (Bonmatin et al. 2019;Humann-Guilleminot et al. 2019;Wu et al. 2020;Zhou et al. 2021;Zheng et al. 2022). In particular, Zhou et al. (2021) reported that the concentrations of NEOs in greenhouses were far higher than those found in the orchard, farm, park and residential areas, with the highest concentration being 459 ng/g in the spring and 252 ng/g in the fall. ...
... Although most of the detected NEO residues were at low levels, all the soil samples we analysed contained multiple NEOs (≥ 2 NEOs), of which 93.29% contained ≥ 4 NEOs. Similarly, several publications also concluded that multiple NEOs occurred ubiquitously in different soils (Humann-Guilleminot et al. 2019;Wu et al. 2020;Yu et al. 2021;Zhou et al. 2021). For instance, Zhou et al. (2021) found that all the 61 soil samples in the spring and 84.30% of the 158 samples in the fall contained ≥ 2 NEOs. ...
Article
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Purpose The benefits associated with the conventional use of neonicotinoids on greenhouse vegetables have lasted for several decades. Extensive use of neonicotinoids could result in their accumulation in the soils, thereby potentially threatening human health through ingestion, dermal contact and inhalation. This study aimed to clarify the pollution characteristics and non-dietary human cumulative risk of neonicotinoids in vegetable greenhouse soils. Materials and methods A total of 283 soil samples were collected from celery, cucumber, pepper and tomato greenhouses across Shandong Province in China and analysed for nine widely used neonicotinoids. Furthermore, the potential health risks for both adults and children were assessed. Results Among all the soil samples, imidacloprid, clothianidin and thiamethoxam were the top three detected neonicotinoids, with detection frequencies of 96.82–99.65%. The three neonicotinoids had higher average concentrations in the soils, with average concentrations of 27.55–157.64 µg/kg. All the soil samples contained at least two neonicotinoids, but most of the detected residues were at low levels with concentrations ranging from 0.02 to 1816.67 µg/kg. The levels of total neonicotinoids (calculated based on a relative potency factor method) in tomato and pepper soils were statistically higher than those in cucumber and celery soils. Although the exposure risk to children was far higher than that to adults, the health risk assessment for each neonicotinoid or total neonicotinoids was within the established safe limits (hazard index range, 1.07 × 10⁻¹⁰ to 1.95 × 10⁻³, < 1). Despite the low health risk, potential hazards of exposure to neonicotinoid-contaminated soils should be continuously assessed due to the low-dose adverse effects and potential accumulation in human tissues. Conclusions Our findings indicate that attention should be given to the neonicotinoids in vegetable greenhouse soils due to their ubiquity and toxicokinetic characteristics.
... In response to these concerns, measures have been taken by the European Union and Switzerland in the form of a moratorium on the use of three molecules (imidacloprid, clothianidin and thiamethoxam) on selected crops that came into force in 2013 (EU Regulation No 485/ 2013). Since January 2019, a new regulation stated a ban of these three molecules in all outdoor crops, restricting them to greenhouses (Bundesamt für Landwirtschaft, 2018) Yet, recent studies have established that, due to high contamination risks from the treated fields to the surrounding areas (Bonmatin et al., 2019;Botías et al., 2016;Humann-Guilleminot et al., 2019b) combined with long persistence in the agroecosystems, NNIs continue to expose a large range of nontarget species even years after the ban (Humann-Guilleminot et al., 2019b;Wintermantel et al., 2020). ...
... In response to these concerns, measures have been taken by the European Union and Switzerland in the form of a moratorium on the use of three molecules (imidacloprid, clothianidin and thiamethoxam) on selected crops that came into force in 2013 (EU Regulation No 485/ 2013). Since January 2019, a new regulation stated a ban of these three molecules in all outdoor crops, restricting them to greenhouses (Bundesamt für Landwirtschaft, 2018) Yet, recent studies have established that, due to high contamination risks from the treated fields to the surrounding areas (Bonmatin et al., 2019;Botías et al., 2016;Humann-Guilleminot et al., 2019b) combined with long persistence in the agroecosystems, NNIs continue to expose a large range of nontarget species even years after the ban (Humann-Guilleminot et al., 2019b;Wintermantel et al., 2020). ...
... A plausible explanation for the high detection rate of NNIs in food boluses would be that the contamination comes through the inhalation of aerosolized NNIs from toxic dust or after a drench application (Girolami et al., 2012;Krupke et al., 2012;Rogers et al., 2019). However, these relatively low concentrations in food boluses, compared to the reported lethal concentrations for a variety of arthropods (Humann-Guilleminot et al., 2019b), may be due to the fact that insects weakened by lethal or sublethal doses of NNIs may be unlikely to enter the diet of Alpine swifts, whose hunting behaviour protects them from being exposed to substantial amounts of NNIs. This low contamination by ingestion is further reflected by the low prevalence of neonicotinoids in the plasma of adults. ...
Article
Monitoring the extent to which wildlife is exposed to the broadly used neonicotinoid insecticides (NNIs) is essential to assess their potential negative effects on biodiversity. Birds are good subjects to assess such exposure, because they inhabit various habitats and they feed at different trophic levels. However, so far, most studies have focused on the contamination of granivorous species. In this study, we assess the concentrations of five NNIs (acetamiprid, clothianidin, imidacloprid, thiacloprid, thiamethoxam) in the carnivorous Barn owl (Tyto alba), and the insectivorous Alpine swift (Tachymarptis melba). NNIs were measured in the Barn owl in feathers collected from nestlings in 2012 (n = 49 broods) and adults in 2016 (n = 58 individuals), and in the Alpine swift from feathers collected from 50 pooled nestling samples from 50 nests between 2004 and 2017 (nestlings raised in five different nests over ten years; n = 50 broods), plasma samples from adults in 2018 (n = 15), and food boluses collected from nestling provisioning adults in 2018 (n = 12). We found that 69% and 56.9% of Barn owl feathers from nestlings and adults respectively contained at least one NNI at measurable concentration. Mean ± SE and median concentrations (in ppb) of total NNIs were 0.66 ± 1.13 and 0.42 for nestlings, and 0.17 ± 0.57 and 0.04 for adults. In the Alpine swift, although we detected no NNI in nestling feathers, we found that 75% of food boluses and 20% adult plasma samples contained at least one NNI at measurable concentration. Mean ± SE and median concentrations (in ppb) of total NNIs were 0.24 ± 0.20 and 0.24 in food boluses, and 0.06 ± 0.13 and 0 in plasma. In view of these results, further research is warranted to determine the extent of contamination in non-granivorous birds and their potential effects.
... The prophylactic abundant usage of non-specific pesticides to combat pest species inevitably harms non-target organisms 14,15 . As systemic pesticides, neonicotinoids are usually applied as seed coatings and only a minor fraction of the active ingredients is actually taken up by the plant roots, resulting in widespread environmental contaminations 16,17 . Even though environmental concentrations of neonicotinoids are often low, they can persist for a long time in the environment as they often have long half-life times (DT 50 ) 18 . ...
... days and DT 90 ranging from 188 to more than 1000 days 20,21 . Chronic exposure of soil-dwelling organisms to fluctuating concentrations and mixtures of neonicotinoids in the range of 1 to > 100 ppb in arable farmlands are likely 17,18 . ...
... Therefore, the extent of the actual exposure of ants in contaminated soils remains elusive. Nonetheless, the neonicotinoid levels used in this experiment can be considered as a worst-case scenario as they were constantly in the upper range of what can be found in arable fields 17,18 . Furthermore, it can be assumed that such arable fields are probably less suitable habitats for ants in the first place because frequent disturbance, e.g. ...
Article
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Pesticides and pathogens are known drivers of declines in global entomofauna. However, interactions between pesticides and viruses, which could range from antagonistic, over additive to synergistic, are poorly understood in ants. Here, we show that in ants the impact of single and combined pesticide and virus stressors can vary across castes and at the colony level. A fully-crossed laboratory assay was used to evaluate interactions between a sublethal dose of the neonicotinoid thiamethoxam and Acute bee paralysis virus (ABPV) in black garden ants, Lasius niger. After monitoring colonies over 64 weeks, body mass, neonicotinoid residues and virus titres of workers and queens, as well as worker behavioural activity were measured. ABPV, but not thiamethoxam, reduced activity of workers. Neonicotinoid exposure resulted in reduced body mass of workers, but not of queens. Further, thiamethoxam facilitated ABPV infections in queens, but not in workers. Overall, virus exposure did not compromise detoxification and body mass, but one colony showed high virus titres and worker mortality. Although the data suggest additive effects at the level of individuals and castes, co-exposure with both stressors elicited antagonistic effects on colony size. Our results create demand for long-term holistic risk assessment of individual stressors and their interactions to protect biodiversity.
... These systemic insecticides are globally most widely used (Simon-Delso et al., 2014) because they can be applied against a broad range of insect pests in most crops and ornamentals. Neonicotinoids are highly persistent, as they can remain for more than one year in plant tissues (Byrne et al., 2014), and for more than ten years in the environment (Humann-Guilleminot et al., 2019). Due to their persistence and negative effects on nontarget beneficial insects (Pisa et al., 2015), the European Union banned the neonicotinoids imidacloprid, thiamethoxam and clothianidin for outdoor uses in 2019. ...
... During this long period, hemipterans can feed on plants and excrete honeydew contaminated with neonicotinoids at different concentrations that may cause lethal and sublethal effects on beneficial insects. Moreover, a recent study has demonstrated that neonicotinoids are present in lower than recommended rates in 93% of organic soils and crops, that had not been treated with neonicotinoids for the last 10 years (Humann-Guilleminot et al., 2019). The presence and concentration of imidacloprid and thiamethoxam in the honeydew samples were further analysed for both soil and foliar-treated trees using LC-MS/MS. ...
... Neonicotinoids are highly persistent in plants, water and soil. In fact, they have been detected in fields in which neonicotinoids have not been applied for more than ten years (Humann-Guilleminot et al., 2019). Under this scenario, it would be beneficial for insects to discriminate and avoid food sources contaminated with neonicotinoids. ...
... Depuis des années, l'EFSA (l'autorité européenne de sécurité des aliments) demandeà l'Europe de remettreà jour les conditions d'évaluation des risques des pesticides. Si le principal contrôle porte sur la toxicitéà court terme sur les abeilles adultes, les recherches montrent que les insecticides peuvent avoir d'autres effets néfastes, notamment la contamination des sols (Humann-Guilleminot et al., 2019). ...
Thesis
La bonne gestion des espaces partagés impose de tenir compte de la multiplicité des parties prenantes qui ont chacune leurs valeurs et leurs objectifs. Elle est soumise à deux problèmes récurrents. Le premier est l’absence de consensus, le second est un consensus sur une solution inefficace dans sa réponse aux problèmes soulevés. Combiner l’aspect participatif avec une aide technique permet d’aborder chacun des deux aspects. Il est possible à la fois d’aider les acteurs dans la prise de décision, tout en aiguillant leur raisonnement vers un résultat cohérent. Afin de fournir une aide technique, nous choisissons d’utiliser la théorie de la viabilité qui propose aux utilisateurs de définir un ensemble de contraintes regroupant les intérêts et objectifs de chacun. Cette méthode possède deux avantages. D’une part, il n’est plus nécessaire d’agréger ou de hiérarchiser les critères. D’autre part, la viabilité permet la prise en compte d’un horizon temporel infini, impliquant le respect de l’équité intergénérationnelle. De plus, nous nous inspirons des techniques utilisées pour la conception de jeux sérieux afin de conférer un aspect éducatif et de sensibilisation à notre outil pour la gestion participative. Ce travail de thèse est axé sur la conception, le développement et l’étude de l’impact d’un outil pour la gestion participative basé sur la théorie de la viabilité. Nous avons implémenté un prototype d’assistant informatique concrétisant les idées proposées dans la thèse. Puis, nous avons mené une première expérimentation de son utilisation afin d’analyser son intérêt et les avantages apportés à la décision et à la négociation. Cette évaluation nous a permis d’étudier l’influence de cet outil sous l’angle de l’aide à décision, de l’aide à la négociation et de la sensibilisation aux enjeux soulevés par le partage des ressources. Une application inspirée du cas des réserves extractivistes brésiliennes nous a permis d’illustrer cette démarche.
... The most efficient strategies to reduce damage caused by mirids on the cacao trees under economic threshold relies essentially on the use of synthetic insecticides of the neonicotinoid family, such as lambda-cyhalothrin and imidacloprid (Ayenor et al. 2007;Mahob 2013;Mahob et al. 2014). Although effective, chemical control has led to insecticide resistance of targeted and/or nontargeted pests; it also has negative effects on the environment, human health and other living organisms such as beneficial arthropods, especially cocoa flower pollinators (Sarmah et al. 2004;Geiger et al. 2010;Manfo Tsagué et al. 2010;Fosu-Mensah et al. 2016;Kibria 2016;Lehmann et al. 2017;Humann-Guilleminot et al. 2019). Risks due to the use of synthetic pesticides, coupled with the stringent legislation of cocoa-importing countries (e.g. ...
Article
The African mirid bug (Sahlbergella singularis) is the most economically important insect pest in cocoa farms. Pesticide management, although controversial due to the adverse effects of these substances on the environment and on human health, remains the main option used for controlling this pest. In the recent decades, the development of alternative approaches to synthetic pesticides is a requirement. Therefore, we used neem oil (NO) and ethanolic extracts (EE) from leaves at different concentrations to evaluate, in vitro, their insecticidal potentials against mirids. Mirid mortality increased significantly with increase in concentrations, values ranged from 32.5 to 92.5 % for EE and 52.5 to 97.5 % for NO. Apart from negative controls, Tween 80 and distilled water, that showed significant low mortality rates, both extracts revealed effectiveness comparable to the reference insecticide used in controlling mirids, except for EE by ingestion. Mirids treated by contact showed significantly high mortality rates (72.5 to 97.5 %) compared to those treated by ingestion (32.5 to 70.0 %). The greatest biological effectiveness values were obtained at a concentration of 8 % by contact exposure: 0.88 ml/ml (NO) and 0.73 g/ml (EE) for LC50 and ≈1 day to both extracts for LT50. Given effectiveness comparable to that of the insecticide, both tested extracts should be considered as effective biopesticides for IPM against mirids, especially S. singularis.
... Nous explorons également une méthode TIER 2 +, qui permettrait de prendre en compte l'intensité des pratiques agricoles et, notamment, la fréquence et l'intensité des pesticides appliqués dans les parcelles. En effet, la nocivité des pesticides, notamment les néonicotinoides, sur la biodiversité est de plus en plus démontrée par les études scientifiques (Humann-Guilleminot et al., 2019). C'est donc un enjeu crucial de mieux les prendre en compte dans les indicateurs de biodiversité appliqués aux paysages agricoles. ...
... Neonicotinoids and their metabolites are highly effective in disrupting neural transmission by binding to acetylcholine receptors in the central nervous system of insects (Matsuda et al., 2020). Due to their systemic nature, high water solubility, and persistence, widespread neonicotinoid contaminations can accumulate and remain in the environment over a long period (Douglas et al., 2020;Humann-Guilleminot et al., 2019). This has become problematic for pollinators, as they can be exposed via contaminated pollen, nectar, or guttationfluids of numerous flowering crops and wildflowers, David et al., 2016;Wintermantel et al., 2020), as well as water (Borsuah et al., 2020). ...
Article
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Insecticides are contributing to global insect declines, thereby creating demand to understand the mechanisms underlying reduced fitness. In the eusocial Hymenoptera, inclusive fitness depends on successful mating of male sexuals (drones) and efficient collaborative brood care by female workers. Therefore, sublethal insecticide effects on sperm and glands used in larval feeding (hypopharyngeal glands (HPG)) would provide key mechanisms for population declines in eusocial insects. However, while negative impacts for bumblebee colony fitness have been documented, the effects of insecticide exposure on individual physiology are less well understood. Here, we show that field-realistic concentrations (4.5 - 40 ng ml⁻¹) of the neonicotinoid insecticide thiamethoxam significantly impair Bombus terrestris sperm and HPGs, thereby providing plausible mechanisms underlying bumblebee population decline. In the laboratory, drones and workers were exposed to five thiamethoxam concentrations (4.5 to 1000 ng ml⁻¹). Then, survival, food consumption, body mass, HPG development, sperm quantity and viability were assessed. At all concentrations, drones were more exposed than workers due to higher food consumption. Increased body mass was observed in drones starting at 20 ng ml⁻¹ and in workers at 100 ng ml⁻¹. Furthermore, environmentally realistic concentrations (4.5 - 40 ng ml⁻¹) did not significantly affect survival or consumption for either sex. However, thiamethoxam exposure significantly negatively affected both sperm viability and HPG development at all tested concentrations. Therefore, the results indicate a trade-off between survival and fitness components, possibly due to costly detoxification. Since sperm and HPG are corner stones of colony fitness, the data offer plausible mechanisms for bumblebee population declines. To adequately mitigate ongoing biodiversity declines for the eusocial insects, this study suggests it is essential to evaluate the impact of insecticides on fitness parameters of both sexuals and workers.
... Because of the broad spectrum of toxicity of pesticides and their extensive use in agriculture, contamination of environmental matrices with pesticide residues from multiple applications is a critical issue (Brühl and Zaller 2019;IPBES IPBES). Only a few studies exist on terrestrial pesticide exposure in wildflowers (Botías et al 2015(Botías et al , 2017David et a. 2016), agricultural soils (Hvězdová et al 2018;Silva et al. 2019) or entire landscapes (Humann-Guilleminot et al. 2019). Pesticide transport from cropping areas into adjacent non-target areas was measured in a playground in Southern Tyrol (Linhardt et al. 2019(Linhardt et al. , 2021. ...
Article
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Insect declines and biodiversity loss have attracted much attention in recent years, but lack of comprehensive data, conflicting interests among stakeholders and insufficient policy guidance hinder progress in preserving biodiversity. The project DINA (Diversity of Insects in Nature protected Areas) investigates insect communities in 21 nature reserves in Germany. All selected conservation sites border arable land, with agricultural practices assumed to influence insect populations. We taught citizen scientists how to manage Malaise traps for insect collection, and subsequently used a DNA metabarcoding approach for species identification. Vegetation surveys, plant metabarcoding as well as geospatial and ecotoxicological analyses will help to unravel contributing factors for the deterioration of insect communities. As a pioneering research project in this field, DINA includes a transdisciplinary dialogue involving relevant stakeholders such as local authorities, poli-cymakers, and farmers, which aims at a shared understanding of conservation goals and action pathways. Stakeholder engagement combined with scientific results will support the development of sound policy recommendations to improve legal frameworks, landscape planning, land use, and conservation strategies. With this transdisciplinary approach, we aim to provide the background knowledge to implement policy strategies that will halt further decline of insects in German protected areas.
... The intensification of agriculture plays a significant role in the decline of biodiversity since several decades (Benton et al., 2003;Green et al., 2005;Dudley and Alexander, 2017). The reiterative use of synthetic pesticides along with the simplification of the farming landscape has negative consequences on ecosystem services associated to biodiversity such as natural pest control based on predation by beneficial insects (Emmerson et al., 2016;Rusch et al., 2016;Humann-Guilleminot et al., 2019). Different measures have been proposed to reconcile agricultural production with biodiversity (see for example Tittonell, 2014). ...
Article
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The role of functional biodiversity for favouring natural regulation and reducing pesticide use in fruit production is generally acknowledged. Although a number of farmers attempt to favour biodiversity through different strategies (e.g. diversified hedges, nesting boxes), they often lack means to evaluate how their actions contribute in practice to functional biodiversity. We assumed here that to create useful and appropriate monitoring methods, it is necessary to take into account the variety of knowledge, perceptions and interests about functional biodiversity. To test our hypothesis, we adopted a comprehensive and participative approach based on interviews and workshops with farmers, advisors and field agronomists involved in apple orchard management. Our objective was to understand their different perceptions and uses of functional biodiversity and then, to design monitoring methods adapted to those perceptions and pre-existing uses. Our findings revealed both a plurality of perceptions of functional biodiversity along with a diversity of objectives and uses of monitoring methods. Based on these results, we identified four main attitudes towards the management of functional biodiversity: the wait-and-see attitude, the naturalist attitude, the regulation attitude and the multifunctional attitude. These attitudes do not correspond to person’s profiles, since one person can adopt different attitudes in regard to different biodiversity components or in regard to the different practices supporting biodiversity. In addition, attitudes can vary over time. The identification of these attitudes allowed us to design, with the workshops’ participants, a guiding framework to create monitoring programs (i.e. combinations of monitoring methods) adapted to a variety of uses and targeted services.
... Neonicitinoids for example, although highly effective against a number of crop pests, have been shown to readily leach into surrounding non-crop areas where pollinators are likely to encounter them and be adversely affected [54]. So pervasive are neonicitinoids that they can also be found in the soil of organic farms [55]. If we are to successfully combat the decline of non-target insect species, very effort must be made to convince farmers to reduce, or even curtail, their use of pesticides and to adopt a fully integrated pest management strategy to crop production [56]. ...
Article
Reports of declines in abundance of a number of insect species have been increasing over the last two decades. These have variously been attributed to climate change, urbanisation, deforestation, agricultural intensification, habitat fragmentation and pesticide usage. The picture has been complicated by the fact that not all insect groups have shown the drastic declines reported for others, flawed methodology, paucity of long-term studies, the lack of data from the tropics with most long-term studies emanating from Europe and North America. In addition, the number of insect groups studied has largely been restricted to charismatic species such as Hymenoptera, Lepidoptera, Coleoptera and Odonata. Despite this, the evidence for long-term declines in insect abundance is incontrovertible. To aid in our understanding of the problem we need to set up more globally coordinated studies, use past data in innovative ways and convince policy makers and governments to support these studies.
... Studies have also found that non-target wild plants nearby fields with seed-treated crops also could incorporate the respective insecticides at variable concentrations, posing an additional exposure route (Botías et al., 2016). Diffuse spread of systemic insecticides has also been proposed after a recent study found that a majority of fields of organic farms, free of insecticides, were contaminated with neonicotinoids (Humann-Guilleminot et al., 2019). Another recent study found that honey dew from phloem-feeding insects on treated plants contained levels of neonicotinoids that were large enough to be toxic to hoverflies feeding on it (Calvo-Agudo et al., 2019), illustrating another potential route of exposure for insects feeding on honey dew, which has previously not been considered. ...
... SDDs have been used in the risk assessment of endocrine disruptors (Kim et al., 2018(Kim et al., , 2020, metals (Cândido et al., 2020;Wang et al., 2015bWang et al., , 2018 and pesticides (Claus and Spanoghe, 2020;Wu et al., 2020) to non-target soil organisms. Recently, Humann-Guilleminot et al. (2019) failed to elaborate a SSD for clothianidin in the soil compartment due to the lack of toxicity data for soil organisms, and Wu et al. (2020) constructed an acute SSD using toxic values of clothianidin derived mostly from tests with insects. Then, a chronic SSD approach could substantially improve the ecological risk assessment (ERA) of clothianidin for in-soil organisms. ...
Article
This study aimed to assess the chronic toxicity and risk of clothianidin in a seed dressing formulation to non-target soil invertebrates. The toxicity assays were performed with two oligochaetes (earthworms Eisenia andrei and enchytraeids Enchytraeus crypticus) and three collembolans (Folsomia candida, Proisotoma minuta and Sinella curviseta) species following ISO protocols. Risk assessment (via Hazard Quotient approach – HQ) was based on the hazardous concentrations for 95% of the species (HC5), derived from chronic Species Sensitivity Distributions (SSD) for clothianidin, and on its predicted environmental concentrations (PEC). Four SSD scenarios were generated with literature and/or this study data, following different data selection criteria (i.e., general, only data from tests using similar formulations, similar soils, or identical soil/formulation). In our experiments, a higher clothianidin toxicity (EC50-based) was found for collembolans (varying from 0.11 to 0.28 mg kg-1 between species) followed by the earthworms (4.35 mg kg-1), while the enchytraeids were the least sensitive (33.5 mg kg-1). HQ indicated a significant risk of clothianidin to soil invertebrates because the estimated PEC were at least 16.6-times higher than HC5 and are expected to affect the whole group of collembolans. Despite the criteria for data inclusion have influenced the HC5 values, no substantial changes were observed for the risk outcomes. To our knowledge, this is the first study assessing the chronic ecological risk of clothianidin to beneficial soil fauna based on a probabilistic SSD approach. Data from this study can help to derive more reliable protection thresholds for clothianidin in soils.
... This reduction of water volume is important because it reduces the risk of drift and runoff and, therefore, the risk of insecticide contamination in non-target organisms of different trophic levels. For example, neonicotinoids occur in 93% of organic soils and crops that had not been treated with neonicotinoids for the last 10 years [31]. Moreover, the reduction of water volume also reduces the risk for human health, including farmers, bystanders and consumers. ...
Article
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Aonidiella aurantii is one of the most damaging armored scales in citrus crops worldwide. To control this pest, high water volume rates are conventionally used. In order to rationalize the pesticide applications in citrus, IVIA developed CitrusVol, a tool that recommends the optimal volume rate based on the vegetation, the pest or disease and the active ingredient. In this study the objectives were: (i) validate CitrusVol as a tool to adjust the spray volume to control A. aurantii and (ii) quantify its environmental and economical advantages. For this, the spray volume adjusted with CitrusVol was compared with the one conventionally used by farmers in 18 applications in seven orchards during two years. The following parameters were evaluated: (i) spray distribution in the canopy, (ii) A. aurantii males trapped per day, and (iii) number of scales per fruit at harvest. CitrusVol reduced the spray volume and the amount of pesticide by 35% on average. Despite this reduction, a satisfactory spray distribution was achieved, and the volume was found to control the pest in a comparable way to the conventional volume. Moreover, CitrusVol saved per application and on average 31.25 h/100 ha of spray operating time, 241.83 L/100 ha of fuel consumption and consequently, the reduction of emissions of CO2 was 631.18 kg/100 ha. Therefore, CitrusVol allows for efficient, low-input and low-impact pesticide applications.
... One study compared residues of currently used pesticides in agricultural soils under conventional and organic management, considering five neonicotinoid insecticides. 8 However, broad scale investigations of various groups of pesticides (e.g., fungicides, herbicides, and insecticides) in organically managed soils are missing. Testing this is of great importance, as pesticide residues of past agricultural management or contamination from conventional fields could especially affect organic agriculture. ...
Article
Pesticides are applied in large quantities to agroecosystems worldwide. To date, few studies assessed the occurrence of pesticides in organically managed agricultural soils, and it is unresolved whether these pesticide residues affect soil life. We screened 100 fields under organic and conventional management with an analytical method containing 46 pesticides (16 herbicides, 8 herbicide transformation products, 17 fungicides, seven insecticides). Pesticides were found in all sites, including 40 organic fields. The number of pesticide residues was two times and the concentration nine times higher in conventional compared to organic fields. Pesticide number and concentrations significantly decreased with the duration of organic management. Even after 20 years of organic agriculture, up to 16 different pesticide residues were present. Microbial biomass and specifically the abundance of arbuscular mycorrhizal fungi, a widespread group of beneficial plant symbionts, were significantly negatively linked to the amount of pesticide residues in soil. This indicates that pesticide residues, in addition to abiotic factors such as pH, are a key factor determining microbial soil life in agroecosystems. This comprehensive study demonstrates that pesticides are a hidden reality in agricultural soils, and our results suggest that they have harmful effects on beneficial soil life.
... Although effective, chemical control has been expensive to farmers and has led to considerable side effects, such as a widespread insecticide resistance for targeted and nontargeted species, a decrease in the diversity and biomass of plants and animals, including useful beneficial arthropods like natural enemies and pollinators, and a general pollution of the environment leading to negative effects on human health (Geiger et al. 2010;Bagny Beilhe et al. 2018b;Humann-Guilleminot et al. 2019). Due to these risks, there is nowadays an increasing societal demand for organic cocoa farming that excludes the use of wide range of synthetic pesticides for cocoa pest and disease management (Babin 2018;Bagny Beilhe et al. 2018b). ...
Article
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Sahlbergella singularis is a major insect pest of cocoa in Cameroon. Conventional insecticides remain the most widely used option for mirid control, which unfortunately have adverse effects on the environment and human health. Improved methods of controlling this species, both environmentally friendly and inexpensive to farmers, are requirements. Varietal control based on the selection of resistant and/or tolerant genotypes can be an interesting approach. Nonetheless, the role of secondary metabolites (SMs) in cocoa defense against mirids is poorly documented; yet, these compounds are reported to be key elements in plant defense against herbivores. For this purpose, SMs of twelve cocoa genotypes were identified and quantified, as well as their impact on food preference by mirids. Food preference was assessed through microtests measuring cocoa attractiveness and antixenosis toward mirids. The results showed that cocoa genotypes were differently accepted as food by mirids, with a significant preference for hybrid IMC60 x SNK605 and a non-preference for T60/887. The ten other cocoa genotypes showed intermediate results. Five SMs classes: alkaloids, flavonoids, polyphenols, saponins, and tannins were identified. Their rates varied between cocoa genotypes: polyphenols > alkaloids > flavonoids > tannins, and saponins. Cocoa genotypes with high total phenolic contents were significantly preferred by S. singularis (rα = 0.86, R2 = 74.0%, P < 0.001), while those with low saponins contents were lowly accepted (rα = − 0.83, R2 = 68.9%, P < 0.015), independently of the levels of other SMs. Given SMs high potential to affect mirid feeding behavior, analyzing cocoa SMs composition may help in early selection of resistant cocoa varieties against S. singularis.
... Neonicotinoids act as an agonist of postsynaptic nicotinic acetylcholine receptors (causing a depolarizing blockade), which leads to paralysis and ultimately death of the affected organism [14]. Moreover, they are systemic and can thus be found in many aquatic-as well as terrestrial compartments, including agricultural soils (treated in preceding years), ecological flower strips, and organic agricultural soils [15][16][17]. Therefore, these broad-spectrum insecticides pose a high risk to non-target organisms [7], and unsurprisingly, numerous studies have demonstrated inadvertent negative sublethal and lethal effects for pollinators [18,19]. ...
Article
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The ubiquitous use of pesticides is one major driver for the current loss of biodiversity, and the common practice of simultaneously applying multiple agrochemicals may further contribute. Insect toxicology currently has a strong focus on survival to determine the potential hazards of a chemical routinely used in risk evaluations. However, studies revealing no effect on survival or even indicating enhanced survival are likely to be misleading, if potential trade-offs between survival and other physiological factors are overlooked. Here, we used standard laboratory experiments to investigate the sublethal (i.e., food consumption) and lethal (i.e., survival) effects of two common agricultural pesticides (Roundup ® and clothianidin) on adult female solitary bees, Osmia bicornis. The data showed no significant effect of the treatment on cumulative survival; however, a significant positive correlation between herbicide and insecticide exposure and age was revealed, i.e., bees exposed to higher dosages lived longer. As no significant differences in daily food consumption were observed across treatment groups, increased food intake can be excluded as a factor leading to the prolonged survival. While this study does not provide data on fitness effects, two previous studies using solitary bees observed significant negative effects of neonicotinoid insecticides on fitness, yet not on survival. Thus, we conjecture that the observed non-significant effects on longevity may result from a trade-off between survival and reproduction. The data suggest that a focus on survival can lead to false-negative results and it appears inevitable to include fitness or at least tokens of fitness at the earliest stage in future risk assessments.
... Five neonicotinoids are currently approved as active substances in the EU for use in plant protection products (PPP), namely acetamiprid, clothianidin, imidacloprid, thiacloprid and thiamethoxam (The European Commission 2018). They can persist and accumulate in the environment (Goulson 2013) and have recently been found in organic soils and seeds (Guilleminot et al. 2019), demonstrating their presence even in soils to which they are not applied. Each neonicotinoid has specific properties concerning its environmental fate (persistence, biodegradability and accumulation) and specific toxicity levels. ...
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Pesticide residues in honey can negatively affect bee health. Although recent studies have detected neonicotinoid residues in honeys from around the world, little is known about how residues relate to land use and vegetation composition. To investigate potential relationships, we sampled multi-floral honey from 30 Apis mellifera hives from urban, agricultural and semi-natural habitats (SNH), identified and quantified three neonicotinoids present (clothianidin, imidacloprid and thiacloprid) using UHPLC-MS, and classified surrounding land use up to 5 km around hive sites. Neonicotinoids were most frequently detected in honeys from hives in agricultural habitats, and 70% of all samples contained at least one of the three neonicotinoid compounds. Imidacloprid was the most frequently detected neonicotinoid (found in 43% of honey samples) followed by clothianidin (40%) and thiacloprid (37%). Almost half (48%) of samples contained at least two neonicotinoids, and two of the 30 samples contained all three. Clothianidin and thiacloprid were more frequently detected in honeys from urban habitats, highlighting that exposure to pesticides does not just occur in agricultural settings. This suggests that pesticide use in urban domestic, sport and amenity contexts, given potential exposure of bees and other pollinators, needs urgent consideration.
... When applied to seeds, soil, or foliage, the neonicotinoids move to the growing tissue of the plant and provide long-term protection against pest insects (Elbert et al., 2008;Simon-Delso et al., 2015). The global popularity of neonicotinoids, combined with their systemic properties and environmental persistence, has resulted in a widespread contamination of the environment with these pesticides (Main et al., 2016;Wood and Goulson, 2017;Humann-Guilleminot et al., 2019). When neonicotinoids are employed as seed treatment, approximately 5% of the neonicotinoid is taken up by the crop plant, whereas most remnant pesticide disperses into the soil and the wider environment (Sur and Stork, 2003). ...
Article
The aim of this study was to estimate the risk posed by imidacloprid (IMI) seed coating to passerine birds of the Pampa Region of Argentina using data specifically generated with the grayish baywing (Agelaioides badius). Median lethal dose (LD50) of the IMI-based formulation tested was 57.11 mg IMI/kg body weight (bw), with intoxication signs starting from 20.6 mg IMI/kg bw. The feed intake rate (FIR) was estimated experimentally as 4.895 g/day per bird, representing 12.43% of bw. It was calculated that the ingestion of 7–10% of the FIR as treated seeds would be enough to achieve the LD50 for sorghum, corn, sunflower, and alfalfa,whereas consumption of 31 and 54% of FIRwas necessary for oat andwheat, respectively. Based on spill data values available in the literature, it was calculated that, for most crops, a baywing would have to forage an area of field corresponding to less than 60 m2 to obtain the number of seeds required to reach the LD50. It was also shown that this number of seeds is coherent with the amount of seeds ingested in a bout. In a pilot study, all grayish baywings fed with millet seeds treated with 3 g IMI/kg died within three to five days of exposure. In Tier I risk assessment, the trigger value was achieved for all crops except soybean and a weight-of-evidence risk assessment was performed. All lines of evidence examined are consistent with the view that grayish baywings, and probably other small farmland birds, are exposed to a risk of acute toxicity and mortality under bothworst-case and mixed-ration exposure scenarios. The possible impacts on bird species calls for an urgent reconsideration of IMI seed coating practices currently approved in the Pampa Region of Argentina and the various parts of the world where this practice is still in use.
... Neonicotinoid insecticides were used extensively over recent decades because they were considered economic, highly effective against a broad spectrum of insect pests, and could be applied in different modes: foliar spray, soil drench, soil granules, injected into irrigation systems, injected directly into trees, or as a seed coating (Jeschke et al., 2011). However, neonicotinoids can be highly persistent in water, plants and soils, where they can remain for years (Table S2) (Byrne et al., 2014;Humann-Guilleminot et al., 2019), and can be highly toxic to beneficial insects, especially pollinators (Pisa et al., 2015) (see oral median lethal dose LD 50 values for honeybees in Table S2; LD 50 is the dose required to cause death of 50% of a tested population after a specified test duration). Due to their high persistence and toxicity to beneficial insects, in 2018 the EU banned use of the neonicotinoids thiamethoxam, imidacloprid and clothianidin on outdoor crops (European Commission, 2018a, 2018c. ...
Article
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Honeydew is the sugar-rich excretion of phloem-feeding hemipteran insects such as aphids, mealybugs, whiteflies, and psyllids, and can be a main carbohydrate source for beneficial insects in some ecosystems. Recent research has revealed that water-soluble, systemic insecticides contaminate honeydew excreted by hemipterans that feed on plants treated with these insecticides. This contaminated honeydew can be toxic to beneficial insects, such as pollinators, parasitic wasps and generalist predators that feed on it. This route of exposure has now been demonstrated in three plant species, for five systemic insecticides and four hemipteran species; therefore, we expect this route to be widely available in some ecosystems. In this perspective paper, we highlight the importance of this route of exposure by exploring: (i) potential pathways through which honeydew might be contaminated with insecticides; (ii) hemipteran families that are more likely to excrete contaminated honeydew; and (iii) systemic insecticides with different modes of action that might contaminate honeydew through the plant. Furthermore, we analyse several model scenarios in Europe and/or the USA where contaminated honeydew could be problematic for beneficial organisms that feed on this ubiquitous carbohydrate source. Finally, we explain why this route of exposure might be important when exotic, invasive, honeydew-producing species are treated with systemic insecticides. Overall, this review opens a new area of research in the field of ecotoxicology to understand how insecticides can reach non-target beneficial insects. In addition, we aim to shed light on potential undescribed causes of insect declines in ecosystems where honeydew is an important carbohydrate source for insects, and advocate for this route of exposure to be included in future environmental risk assessments.
... www.nature.com/scientificreports/ in the agricultural landscape remain scarce compared to the pesticide water monitoring that has been in place on country-wide scales for decades as a requirement of the EU Water Framework Directive 22 . The first data on pesticide residues measured in soils from agricultural fields have recently emerged [23][24][25] , and a landscape-scale assessment for exposure has been conducted for neonicotinoids 26 . Residues in pollen, a food source for honey bees (Apis mellifera) and other pollinating insects, have been monitored for years 27,28 , revealing bee exposure to multiple pesticides and seasonal changes of pesticide residue mixtures 29 . ...
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In Germany, the decline of insect biomass was observed in nature conservation areas in agricultural landscapes. One of the main causal factors discussed is the use of synthetic pesticides in conventional agriculture. In a Germany-wide field study, we collected flying insects using Malaise traps in nature conservation areas adjacent to agricultural land. We used a multi-component chemical trace element analysis to detect 92 common agricultural pesticides in ethanol from insect traps sampled in May and August 2020. In total, residues of 47 current use pesticides were detected, and insect samples were on average contaminated with 16.7 pesticides. Residues of the herbicides metolachlor-S, prosulfocarb and terbuthylazine, and the fungicides azoxystrobin and fluopyram were recorded at all sites. The neonicotinoid thiacloprid was detected in 16 of 21 nature conservation areas, most likely due to final use before an EU-wide ban. A change in residue mixture composition was noticeable due to higher herbicide use in spring and increasing fungicide applications in summer. The number of substances of recorded residues is related to the proportion of agricultural production area in a radius of 2000 m. Therefore, a drastic pesticide reduction in large buffers around nature conservation areas is necessary to avoid contamination of their insect fauna.
... Among pesticides, neonicotinoids (NN), which are selectively neurotoxic and bind to nicotinic acetycholine receptors (nAChRs), are of special concern for their impacts on the environment and human health since they are the most widely used class of insecticides worldwide [6] and are ubiquitously found in the environment [7], wildlife [8], and various foods [9,10]. NN use has been restricted in some part of the world due to their significant toxicity to non-target insects such as bees [11]. ...
Article
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Background Neonicotinoids (NN) are selective neurotoxic pesticides that bind to insect but also mammal nicotinic acetycholine receptors (nAChRs). As the most widely used class of insecticides worldwide, they are ubiquitously found in the environment, wildlife, and foods, and thus of special concern for their impacts on the environment and human health. nAChRs are vital to proper brain organization during the prenatal period and play important roles in various motor, emotional, and cognitive functions. Little is known on children’s contamination by NN. In a pilot study we tested the hypothesis that children’s cerebro-spinal fluid (CSF) can be contaminated by NN. Methods NN were analysed in leftover CSF, blood, and urine samples from children treated for leukaemias and lymphomas and undergoing therapeutic lumbar punctions. We monitored all neonicotinoids approved on the global market and some of their most common metabolites by ultra-high performance liquid chromatography-tandem mass spectrometry. Results From August to December 2020, 14 children were consecutively included in the study. Median age was 8 years (range 3–18). All CSF and plasma samples were positive for at least one NN. Nine (64%) CSF samples and 13 (93%) plasma samples contained more than one NN. Thirteen (93%) CSF samples had N-desmethyl-acetamiprid (median concentration 0.0123, range 0.0024–0.1068 ng/mL), the major metabolite of acetamiprid. All but one urine samples were positive for ≥ one NN. A statistically significant linear relationship was found between plasma/urine and CSF N-desmethyl-acetamiprid concentrations. Conclusions We have developed a reliable analytical method that revealed multiple NN and/or their metabolites in children’s CSF, plasma, and urine. Our data suggest that contamination by multiple NN is not only an environmental hazard for non-target insects such as bees but also potentially for children.
... Often, the synthetic fertilizer that is necessary to drive monoculture production is not taken up by the crop or stored in soil organic matter, meaning some portion of the fertilizer remains in the soil and is therefore susceptible to loss and movement to other ecosystems (Robertson and Vitousek, 2009). Similarly, the pesticides which are required to control otherwise untenable pest levels rarely remain confined to their intended targets (Kolpin et al., 1998;Humann-Guilleminot et al., 2019). ...
Article
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There is no shortage of data demonstrating that diversified cropping systems can sustain high levels of productivity with fewer external inputs and lower externalities compared to more simplified systems. Similarly, data exist indicating diverse cropping systems have greater capacity to buffer against and adapt to weather extremes associated with climate change. Yet, agriculture in the US Corn Belt and other major crop production regions around the world continues to move toward simplified rotations grown over increasingly large acreages. If our goal is to see more of the agricultural landscape made up of diverse agricultural systems and the ecosystem services they provide, it is critical we understand and creatively address the factors that both give rise to monocultures and reinforce their entrenchment at the exclusion of more diversified alternatives. Using the current state of farming and agriculture policy in the US as a case study, we argue that a pernicious feedback exists in which economic and policy forces incentivize low diversity cropping systems which then become entrenched due, in part, to a lack of research and policy aimed at enabling farming practices that support the diversification of cropping systems at larger spatial scales. We use the recent example of dicamba-resistant crops to illustrate the nature of this pernicious feedback and offer suggestions for creating “virtuous feedbacks” aimed at achieving a more diversified agriculture.
... All samples were analysed by ultra-high performance liquid chromatography-tandem mass spectrometry using an Acquity UPLC™ (Waters) coupled to a TQ-S triple quadrupole mass spectrometer (Waters) using a well-established method (Bonmatin et al., 2019;Humann-Guilleminot et al., 2019a;Kammoun et al., 2019). Blank water samples (2-3 per batch of 50-80 samples) were included in the runs to ascertain the quality of the analysis obtained. ...
Article
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Synthetic pesticides such as neonicotinoids are commonly used to treat crops in tropical regions, where data on environmental and human contamination are patchy and make it difficult to assess to what extent pesticides may harm human health, especially in less developed countries. To assess the degree of environmental and human contamination with neonicotinoids we collected soil, water and people's hair in three agricultural regions of the Philippines and analysed them by ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS-MS). Five neonicotinoids, namely acetamiprid, clothianidin, imidacloprid, thiacloprid and thiamethoxam were targeted. Residues of neonicotinoids were found in 78% of 67 soil samples from the three provinces. Total neonicotinoid loads ranged on average between 0.017 and 0.89 μg/kg in soils of rice, banana and vegetable crops, and were 130 times higher (113.5 μg/kg) in soils of a citrus grove. Imidacloprid was the most prevalent compound at an average of 0.56 μg/kg in soil while thiacloprid was below the limit of detection. Half of the eight water samples from a rice field and nearby creek contained residues of imidacloprid (mean 1.29 ng/L) and one contained thiamethoxam (0.15 ng/L). Residues of neonicotinoids were found in 81% of 99 samples of people's hair from the surveyed regions (average total concentrations 0.14 to 1.18 ng/g, maximum 350 ng/g). Hair residue levels correlated well with the concentrations of thiamethoxam and total residues in soils from the same locality (r=0.98). The presence of thiacloprid in 15% of the hair samples but not in soil samples suggests an additional route of exposure among people, which is most likely to be through ingestion of agricultural food and drinks available in the market.
... The neonicotinoid insecticide in our sample, imidacloprid, had a grace period until 2022, while other neonicotinoids have been banned for outdoor use in the EU since 2018 (EC, 2021b). Neonicotinoids have been linked to detrimentally affect insects (Simon-Delso et al., 2015;van der Sluijs, 2020), soil organisms (van Hoesel et al., 2017), and were found in organically farmed soils and crops (Humann-Guilleminot et al., 2019) and in carnivorous and insectivorous birds (Humann-Guilleminot et al., 2021). Emergency authorizations in Austria (and other EU member states) still allowed their use for short periods in justifiable cases. ...
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Little is known about (i) how numbers and concentrations of airborne pesticide residues are influenced by land use, interactions with meteorological parameters, or by substance-specific chemo-physical properties, and (ii) what potential toxicological hazards this could pose to non-target organisms including humans. We installed passive air samplers (polyurethane PUF and polyester PEF filter matrices) in 15 regions with different land uses in eastern Austria for up to 8 months. Samples were analyzed for 566 substances by gas-chromatography/mass-spectrometry. We analyzed relationships between frequency and concentrations of pesticides, land use, meteorological parameters, substance properties, and season. We found totally 67 pesticide active ingredients (24 herbicides, 30 fungicides, 13 insecticides) with 10–53 pesticides per site. Herbicides metolachlor, pendimethalin, prosulfocarb, terbuthylazine, and the fungicide HCB were found in all PUF samplers, and glyphosate in all PEF samplers; chlorpyrifos-ethyl was the most abundant insecticide found in 93% of the samplers. Highest concentrations showed the herbicide prosulfocarb (725 ± 1218 ng sample⁻¹), the fungicide folpet (412 ± 465 ng sample⁻¹), and the insecticide chlorpyrifos-ethyl (110 ± 98 ng sample⁻¹). Pesticide numbers and concentrations increased with increasing proportions of arable land in the surroundings. However, pesticides were also found in two National Parks (10 and 33 pesticides) or a city center (17 pesticides). Pesticide numbers and concentrations changed between seasons and correlated with land use, temperature, radiation, and wind, but were unaffected by substance volatility. Potential ecotoxicological exposure of mammals, birds, earthworms, fish, and honeybees increased with increasing pesticide numbers and concentrations. Human toxicity potential of detected pesticides was high, with averaged 54% being acutely toxic, 39% reproduction toxic, 24% cancerogenic, and 10% endocrine disrupting. This widespread pesticide air pollution indicates that current environmental risk assessments, field application techniques, protective measures, and regulations are inadequate to protect the environment and humans from potentially harmful exposure.
... Exposure at the hive has detected banned or misused pesticides in bee products (Ruiz-Toledo et al., 2018;Woodcock et al., 2018). In some cases, studies report the HQ not correlated with landscape factor of interest or relationship unclear Stoner and Eitzer, 2013;Frazier et al., 2015;Nai et al., 2017;Tosi et al., 2018;El Agrebi et al., 2019;Humann-Guilleminot et al., 2019Smart et al., 2016McArt et al., 2017;Calatayud-Vernich et al., 2018;Ruiz-Toledo et al., 2018;Stoner et al., 2019Urbanowicz et al., 2019 Sixteen papers using HQ at the hive to understand landscape context. These papers are divided into two categories: classifications based off percent land class in the foraging radius of the hive, and site-type classifications where only the immediate surroundings were considered. ...
Article
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Estimates of pesticide application hazards have grown to be one of the most common methodologies for evaluating the impact of pest management practices on honey bees. Typically, hazards are estimated by calculating a Hazard Quotient (HQ), which is based on acute toxicity data for different pesticides and the quantity of those pesticides applied to a field or detected on bees and matrices associated with their hive (honey, wax, pollen, and/or bee bread). Although use of HQ is widespread, there have been few reviews of this methodology, particularly with focus on how effective this method is at predicting effects of pesticides on hives. We evaluated 36 relevant papers, containing calculations of HQ to estimate hazards to honey bees. We observed that HQ was primarily calculated using two different approaches: (1) from the concentration of pesticides in the food, hive, or tissues of honey bees or (2) using the field application rate of the active ingredient as the estimation of pesticide hazard. Within and between HQ calculation methods, thresholds vary widely with some HQ thresholds set below 1 and others set at 10,000. Based on our review we identify key weakness with current HQ methodology and how studies relate HQ to honey bee health endpoints. First, HQ thresholds from studies of pesticides in hives are not based on the same pesticide consumption models from the EPA, potentially overestimating the risk of impacts to colonies. Conversely, HQ estimates calculated from field application rates are not based on eco-toxicological estimates of field exposure, resulting in an overestimation of pesticide reaching colonies. We suggest it is for these reasons that there is poor correspondence between HQ and field-level honey bee health endpoints. Considering these challenges, HQ calculations should be used cautiously in future studies and more research should be dedicated to field level exposure models.
... Pest insects, however, have been causing large losses to crop yields since crop domestication about ten thousand years ago 3,4 . Applications of pesticides and fertilizers are important for improving yields, however, over-use of synthetic insecticides and fertilizers may have negative impacts on agricultural sustainability and human health 5,6 . Moreover, pest populations may outbreak more frequently and more intensely under climate change 7-9 posing a greater threat to global food security. ...
Article
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Temperature has a large influence on insect abundances, thus under climate change, identifying major drivers affecting pest insect populations is critical to world food security and agricultural ecosystem health. Here, we conducted a meta-analysis with data obtained from 120 studies across China and Europe from 1970 to 2017 to reveal how climate and agricultural practices affect populations of wheat aphids. Here we showed that aphid loads on wheat had distinct patterns between these two regions, with a significant increase in China but a decrease in Europe over this time period. Although temperature increased over this period in both regions, we found no evidence showing climate warming affected aphid loads. Rather, differences in pesticide use, fertilization, land use, and natural enemies between China and Europe may be key factors accounting for differences in aphid pest populations. These long-term data suggest that agricultural practices impact wheat aphid loads more than climate warming.
... Arthropods include numerous agricultural pests, as well as key species that play a major role as vectors of pathogens, including malaria, dengue, Zika virus, lymphatic filariasis, Lyme disease, and many others [1,2]. Their control has a long history, and it is still routinely achieved through massive applications of synthetic insecticides [3][4][5], with severe effects on human health and the environment, long-term sub-lethal effects [6][7][8][9][10], and the quick development of resistance in the targeted species [11][12][13]. In the attempt to discover novel active ingredients for insecticidal, acaricidal, and repellent formulations, botanical products have been largely investigated [14][15][16], outlining their scarce toxicity to vertebrates [17], as well as their multiple modes of action on arthropods, which strongly reduce the risk of resistance development [18,19]. ...
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Several species of the family Apiaceae are aromatic herbs that produce essential oils usable on an industrial scale for pharmaceutical, cosmetic, and food purposes. In particular, some essential oils, such as green insecticides for example, may replace synthetic insecticides, keeping most of their efficacy and avoiding environmental pollution or human poisoning. In the present study, we explored the insecticidal potential of Ridolfia segetum (L.) Moris essential oil (EO) against three different pests: Culex quinquefasciatus Say, Musca domestica L., and Spodoptera littoralis (Boisduval). For this purpose, the EO was obtained by hydrodistillation of flowers and its composition was achieved by gas chromatography/flame ionization detection (GC/FID) and gas chromatography/mass spectrometry (GC/MS). This EO was rich in α-phellandrene (49.3%), β-phellandrene (9.2%), terpinolene (20.7%), and piperitenone oxide (5.9%). Concerning the mosquitocidal efficacy, the EO showed noteworthy toxicity against C. quinquefasciatus 3rd instar larvae, with a LC50 = 27.1 µL L−1 and LC90 = 42.5 µL L−1. Regarding M. domestica, a different toxicity of the R. segetum EO was found on male and female flies, calculating LD50 values of 10.5 and 50.8 µg adult−1, respectively. The EO was also toxic to S. littoralis 3rd instar larvae, achieving LD50 and LD90 values of 37.9 and 99.6 µg larva−1, respectively. Overall, this flower EO, extracted from a traditional Sicilian food plant, merits further investigation for the development of green insecticide formulations to be used in real world conditions, pending a careful assessment of non-target toxicity on beneficial organisms.
Article
Neonicotinoids from insecticidal seed coatings can contaminate soil in treated fields and adjacent areas, posing a potential risk to nontarget organisms and ecological function. To determine if cover crops can mitigate neonicotinoid contamination in treated and adjacent areas, we measured neonicotinoid concentrations for three years in no-till corn-soybean rotations, planted with or without neonicotinoid seed coatings, and with or without small grain cover crops. Although neonicotinoids were detected in cover crops, high early season dissipation provided little opportunity for winter-planted cover crops to absorb significant neonicotinoid residues; small grain cover crops failed to mitigated neonicotinoid contamination in either treated or untreated plots. As the majority of neonicotinoids from seed coatings dissipated shortly after planting, residues did not accumulate in soil, but persisted at concentrations below 5 ppb. Persistent residues could be attributed to historic neonicotinoid use and recent, nearby neonicotinoid use. Tracking neonicotinoid concentrations over time revealed a large amount of local interplot movement of neonicotinoids; in untreated plots, contamination was higher when plots were less isolated from treated plots.
Article
This work investigated the preparation of Ti/Sb–SnO2 electrode co-doped with graphene and europium and the electrochemical degradation of clothianidin in aqueous solution with Ti/Sb–SnO2-Eu&rGO electrode. The physicochemical properties of different electrodes were characterized by using the scanning electron microscopy, X-ray diffraction, oxygen evolution potential and cyclic voltammetry tests. The results indicated that the Ti/Sb–SnO2-Eu&rGO electrodes have a compact structure and fine grain size and have a higher oxygen evolution overpotential than Ti/Sb–SnO2-None, Ti/Sb–SnO2-Eu and Ti/Sb–SnO2-rGO electrodes. Among the four electrodes, the Ti/Sb–SnO2-Eu&rGO electrode showed the highest efficiency and was chosen as the experimental electrode. The main influence factors on the degradation of clothianidin, such as initial pH, electrolyte concentration, current density and initial concentration of clothianidin, were analyzed. The results showed that the removal rate of clothianidin can reach 96.44% under the optimal conditions for 120 min treatment. Moreover, a possible degradation pathway including the fracture of internal bonds of clothianidin such as the N–N bond, the C–N bond that connects nitroguanidine to the thiazole ring and mineralization was elucidated by intermediate products identified by HPLC-MS method and Fourier transform infrared spectroscopy (FTIR). This paper introduces the Ti/Sb–SnO2-Eu&rGO electrode into an electrocatalytic degradation system and could provide basic data and technique support and guidance for the clothianidin wastewater pollution control.
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Soils harbour highly‐diverse invertebrate communities that play important roles for ecosystem services, including the mitigation of environmental pollution. Chemical stressors, such as pesticides, pharmaceuticals and metals, are being increasingly spread into ecosystems due to human activities. While it is crucial to predict the consequences of chemical stressors for soil biodiversity, chemical toxicity is often assessed using individuals or populations in laboratory cultures. There has been no systematic evaluation of the evidence documenting the impacts of chemical stressors on diverse, natural soil communities. Here, we use a comprehensive literature review of 274 studies to evaluate the current state of knowledge about the effects of chemicals on soil fauna communities. Most research has had limited spatial scope, with noteworthy gaps in the regions that are potentially the most threatened by soil pollution (Southern Hemisphere). Furthermore, reports generally were constrained to a few emblematic soil fauna groups (nematodes, collembola and earthworms) and chemical stressors (metals). Future research should address biases in spatial distribution of studies, as well as the taxonomic groups and chemical compounds considered. Specifically, emphasis on indirect effects mediated by species interactions, ecosystem functioning and interactive effects of stressors and climate change, currently lacking in the literature, is needed to improve soil‐biodiversity conservation and restoration efforts, as well as predictions of global diversity change.
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Pierce’s disease is of major concern for grapevine (Vitis vinifera) production wherever the bacterial pathogen Xylella fastidiosa and its vectors are present. Long-term management includes the deployment of resistant grapevines such as those containing the PdR1 locus from the wild grapevine species Vitis arizonica, which do not develop Pierce’s disease symptoms upon infection. However, little is understood about how the PdR1 locus functions to prevent disease symptom development. Therefore, we assessed the concentrations of plant defense-associated compounds called phenolics in healthy and X. fastidiosa-infected PdR1-resistant and susceptible grapevine siblings over time. Soluble foliar phenolic levels, especially flavonoids, in X. fastidiosa-infected PdR1-resistant grapevines were discovered to be significantly lower than those in infected susceptible grapevines. Therefore, it was hypothesized that PdR1-resistant grapevines, by possessing lowered flavonoid levels, affects biofilm formation and causes reduced X. fastidiosa intra-plant colonization, thus limiting the ability to increase pathogen populations and cause Pierce’s disease. These results therefore reveal that differences in plant metabolite levels might be a component of the mechanisms that PdR1 utilizes to prevent Pierce’s disease.
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During the Green Revolution, older classes of insecticides contributed to biodiversity loss by decreasing insect populations and bioaccumulating across food webs. Introduction of Integrated Pest Management (IPM) improved stewardship of insecticides and promised fewer non-target effects. IPM adoption has waned in recent decades, and popularity of newer classes of insecticides, like the neonicotinoids, has surged, posing new and unique threats to insect populations. In this review, we first address how older classes of insecticides can affect trophic interactions, and then consider the influence of neonicotinoids on food webs and the role they may be playing in insect declines. We conclude by discussing challenges posed by current use patterns of neonicotinoids and how their risk can be addressed.
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In this study, the artificial soil poisoning method was used to explore the antioxidative stress mechanism and gene changes of earthworms (Eisenia foetida) after application of nitenpyram. The toxic effects of nitenpyram on earthworms were combined with the method called the second-generation integrated biomarker response index method (IBRv2) to be comprehensively analyzed by studying the reactive oxygen species (ROS) content, superoxide dismutase (SOD) activity, catalase (CAT) activity, glutathione S-transferase (GST) activity, malondialdehyde (MDA) content and DNA damage degree in earthworms. The results showed that the ROS content in the high-concentration (2.5 mg/kg) nitenpyram treatment group changed significantly. The changes of antioxidant enzymes in earthworms were also obvious. In terms of SOD enzyme activity, under the induction of nitenpyram, SOD activity in the 1 mg/kg and 2.5 mg/kg treatment groups was significantly enhanced. The concentration-treated group could all affect the activity of earthworm detoxifying enzyme GST. Earthworm DNA olive tail in the nitenpyram treatment group with different concentrations was mainly concentrated at low and medium levels at 21d, and the proportion was the largest during the whole exposure period, showing a significant dose-effect relationship. This study confirms that nitenpyram not only has a toxic effect on the physiological and biochemical indicators of earthworms, but also cannot be underestimated on its genetic level.
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Residues of pesticides not allowed in organic farming are often found in organic food. A large number of samples are being tested by organic certifiers, but the sampling methods often do not allow to determine if such residues stem from prohibited pesticide use by organic farmers, from mixing organic with conventional products, from short-range spray-drift from neighbour farms, from the ubiquitous presence of such substances due to long-distance drift, or from other sources of contamination. Eight case studies from different crops and countries are used to demonstrate that sampling at different distances from possible sources of short distance drift allows in most cases to differentiate deliberate pesticide application by the organic farmer from drift. Datasets from 67 banana farms in Ecuador, where aerial fungicide spraying leads to a heavy drift problem, were subjected to statistical analysis. A linear discriminant function including four variables was identified for distinguishing under these conditions application from drift, with an accuracy of 93.3%.
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Pestizide werden primär in der Landwirtschaft, aber auch im Siedlungsraum und in weiteren Bereichen eingesetzt. Als Pflanzenschutzmittel vermindern sie Ertrags- oder Qualitätseinbussen durch Schadorganismen. Der heutige Pestizideinsatz belastet aber die Umwelt und insbesondere die Biodiversität beträchtlich. Trotz Wissenslücken sind die unerwünschten Auswirkungen gut dokumentiert. Das Faktenblatt nimmt spezifisch die Auswirkungen von Pestiziden auf Umwelt, Biodiversität und Ökosystemleistungen in den Blick und zeigt mögliche Handlungsansätze für Politik und Gesellschaft zur Reduktion der unerwünschten Nebenwirkungen des Pestizideinsatzes auf. Nicht thematisiert werden im Faktenblatt etwa die Bedeutung von Pestiziden für die landwirtschaftliche Produktion oder die Auswirkungen auf die menschliche Gesundheit.
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Neonicotinoid insecticides (NIIs) are extensively used worldwide and frequently detected in the environment. The human and ecological risks associated with the occurrence of NIIs in agricultural zones are of high importance. The present study highlights the regional occurrence and human exposure risks of NIIs in agricultural soil within the Pearl River Delta (PRD), South China. Six neonicotinoids, i.e., imidacloprid, clothianidin, acetamiprid, imidaclothiz, dinotefuran, and flonicamid, were measured in 351 soil samples from Zengcheng, a typical agricultural zone. The soil samples were categorized into three groups based on cultivated plants: vegetables, rice, and fruits. At least one of these neonicotinoid insecticides was detected in 95% of the soil samples. The levels of ∑6NII (range (median)) were 0.26−390 (23), 0.26−280 (6.1), and 0.26−120 (5.0) ng g⁻¹ dry weight in soil samples from vegetable farms, rice paddies, and fruit farms, respectively. Neonicotinoids were detected more frequently and at statistically higher concentrations in vegetable farms than in both rice paddies and fruit farms. This is likely ascribed to higher application frequencies of NIIs in vegetable farms due to higher planting frequencies. The hazard index values for human exposure to NIIs in the agricultural soils were all below 1, suggesting negligible non-cancer risks. The current residual levels of NIIs in the soils could however pose sub-lethal or acute effects to non-target terrestrial organisms such as earthworms. The present study suggests that more information is needed regarding NIIs contamination in soils from agricultural regions of South China to ensure that human and ecological risk from exposure to these compounds can be fully addressed.
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Pesticide residues are much lower in organic than in conventional food. The article summarizes the available residue data from the EU and the U.S. organic market. Differences between samples from several sources suggest that organic products are declared conventional, when they have residues—but the origin of the residues is not always investigated. A large number of samples are being tested by organic certifiers, but the sampling methods often do not allow to determine if such residues stem from prohibited pesticide use by organic farmers, from mixing organic with conventional products, from short-range spray-drift from neighbour farms, from the ubiquitous presence of such substances due to long-distance drift, or from other sources of contamination. Eight case studies from different crops and countries are used to demonstrate that sampling at different distances from possible sources of short-distance drift in most cases allows differentiating deliberate pesticide application by the organic farmer from drift. Datasets from 67 banana farms in Ecuador, where aerial fungicide spraying leads to a heavy drift problem, were subjected to statistical analysis. A linear discriminant function including four variables was identified for distinguishing under these conditions application from drift, with an accuracy of 93.3%.
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The current study sought to assess the residual levels of neonicotinoid insecticides (NEO) in organic and conventional green tea leaves produced in Japan. A total of 103 tea leaves (thus, 42 organic and 61 conventional), were sampled from grocery stores in Japan. Concentrations of NEOs in the tea leaves were quantified using LC–MS/MS; and the data was used to estimate maximum daily intakes of NEOs within the Japanese population. Seven native NEO compounds and one NEO metabolite were detected in both organic and conventional tea leaves. Detection frequencies (%Dfs) of NEOs in the tea samples (n = 103) were found in the decreasing order; thiacloprid (84.47 %) > dinotefuran (74.76 %) > imidacloprid (69.90 %) ≈ clothianidin (69.90 %) > dm-acetamiprid (63.11 %) > thiamethoxam (58.25 %) > acetamiprid (4.85 %) > nitenpyram (1.94 %). About 94.20 % of the tea leaves contained two or more NEO compounds simultaneously. The %Dfs of NEOs were relatively lower in organic tea leaves, compared to the conventional tea leaves. Various percentile concentrations of NEOs were far lower in organic tea leaves, compared to the conventional tea leaves. The maximum daily intakes of NEOs through consumption of tea (MDIgt) were also lower for organic tea leaves, compared to the conventional tea samples.
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Temperature drastically determines insect abundances, thus under climate change, identifying major drivers affecting pest insect populations is critical to world food security and agricultural ecosystem health. Here, we conducted a meta-analysis with data obtained from 120 studies across China and Europe from 1970 to 2017 to reveal the roles of climate and agricultural practices in determining populations of wheat aphids. We showed aphid loads on wheat had distinct patterns between these two regions, with a significant increase in China but decrease in Europe over this time period. Although average winter and growing season temperatures increased over this period in both regions, we found no evidence showing climate warming affected aphid loads. Rather, differences in pesticide use, fertilization, land use, and natural enemies between China and Europe may be key factors accounting for differences in aphid pest populations. These findings provide insights for developing effective agroecosystem management under global change. These long-term data suggest that climate change may not be the most important driver of agricultural pest loads. Therefore, under global environmental change, consideration of multiple factors at large spatial-temporal scales will likely provide more insights for developing effective agroecosystem management to safeguard world food security.
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Ground-cover vegetation attracts and harbors beneficial insects to the agrosystem, playing an important role in conservation biological control. Integrated pest management (IPM) program guidelines recommend the implantation of sowed or resident wild covers in perennial crops. Given the high-quality fruit requirements, even in IPM programs, insecticides can be required in citrus crops. This study presents, over a year, the levels of neonicotinoids (thiamethoxam and imidacloprid) in not-target ground-cover wildflowers growing spontaneously in citrus orchards after foliar treatment of citrus trees. The presence and persistence of these neonicotinoids in different wildflower species were studied. Concentrations of thiamethoxam and imidacloprid in whole wildflowers ranged from < method quantification limit (MQL) to 52.9 ng g⁻¹ and from < MQL to 98.6 ng g⁻¹, respectively. Thiamethoxam was more frequently detected than imidacloprid. Thiamethoxam and imidacloprid were detected up to 336 and 230 days after treatment, respectively. The highest detection frequencies (100%) and highest thiamethoxam and imidacloprid mean concentrations (26.0 ± 7.3 ng g⁻¹ and 11.0 ± 10.6 ng g⁻¹, respectively) occurred in wildflowers collected 9 days after the treatments. Since application, a clear decrease in the concentration of both compounds and differences in the accumulation depending on wildflower species were observed. Cross contamination was detected, indicating a transport from adjacent treated plots. Maintaining a cover crop in citrus orchards may lead to detrimental effects on non-target arthropods if these neonicotinoid compounds are used for pest control since they can entail a chronic exposure during at least 230 days for imidacloprid and 336 days for thiamethoxam.
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Pesticides are synthetic chemicals that destroy pests and insects, improving vegetation and damaging the ruling class. Pesticides gain the vegetation; However, the protective use of pesticides goes against the traditional ethics of Integrated Pest Management (IPM), leading to environmental concerns. It has been observed that neonicotinoid pesticides and their metabolites can continue and accumulate in soils. They are freely soluble in water and compulsive, draining into waterways, and more are found in environmental samples, eventually affecting human well-being. Therefore, regional instability, the traditional principles, and anthropogenic versus natural origin of conceivably dangerous title pesticide in soils and water assessment are precariously main to evaluate human impact. This review article mainly focuses on extensive information about the sample preparation methods, discovery methods, and the developed systems to samples from various fields of soils and water to detect the neonicotinoids.
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The use of insecticides, especially neonicotinoids (NEOCs), poses a significant threat to honey bees, thus prompting the EU to ban all outdoor uses of clothianidin, imidacloprid, and thiamethoxam. However, due to the persistence of NEOCs, as well as the fact that certain NEOCs are in use in some areas of the world, exposure to them is still an on-going issue. In the present study, we used laboratory acute toxicity test to examine the effects of sublethal concentrations (resulting in consumed doses approximately 50, 20, and 5 times below LD50) of thiacloprid and clothianidin on selected parameters of antioxidative defense (superoxide dismutase, catalase, glutathione S-transferase activities), oxidative status (reduced glutathione, protein thiols, malondialdehyde), neurotoxicity (acetylcholinesterase activity), and immune response (prophenoloxidase and phenoloxidase activities) in honey bees. Results indicated that both neonicotinoids’ sublethal concentrations promote oxidative stress in honey bees and affect their immune defense. NEOCs impair detoxification abilities through reduced glutathione S-transferase activity, as well as disturb immune response due to decreased prophenoloxidase and phenoloxidase activities, which can explain the high toxicity of these substances to honey bees.
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The use of synthetic pesticides is not allowed in organic production, but traces of synthetic pesticides are regularly detected in organic food. To safeguard the integrity of organic production, organic certifiers are obliged to investigate the causes for pesticide residues on organic food, entailing high costs to the organic sector. Such residues can have various origins, including both fraud and unintentional contamination from the environment. Because the knowledge about contamination from environmental sources is scattered, this review provides an overview of pathways for unintentional and technically unavoidable contamination of organic food with synthetic pesticides in Europe. It shows that synthetic pesticides are widely present in all environmental compartments. They originate from applications in the region, in distant areas or from historical use. Transition into the food chain has been demonstrated by various studies. However, large uncertainties remain regarding the true pesticide contamination of the environment, their dynamics and the contamination risks for the food chain. Organic operators can take certain measures to reduce the risks of pesticide contamination of their products, but a certain extent of pesticide contamination is technically unavoidable. The present paper indicates that (i) a potential risk for pesticide residues exists on all organic crops and thus organic operators cannot meet a ‘zero-tolerance’ approach regarding pesticide residues at the moment. (ii) Applying a residue concentration threshold to distinguish between cases of fraud and unavoidable contamination for all pesticides is not adequate given the variability of contamination. More reliable answers can be obtained with a case-by-case investigation, where evidence for all possible origins of pesticide residues is collected and the likelihood of unavoidable contamination and fraud are estimated. Ultimately, for organic certification bodies and control authorities it will remain a challenge to determine whether a pesticide residue is due to neglect of production rules or technically unavoidable.
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The populations of meadow birdsMeadow birds in pastoral landscapes have declined seriously since 1970. Apart from changes in land management, this decline could also be related to pesticides in the environment and, consequently, fewer insects. On 15 conventional stock farms and 9 organic stock farms in Gelderland in The NetherlandsNetherlands, The, samples of concentrated feed, manure and soil were found to contain ecologically significant concentrations of 134 different fungicides, herbicidesHerbicide, insecticidesInsecticides and biocides. No sample was free of pesticides. On average, pesticide residuesPesticidesresidues in concentrated feed were 3.7 times lower in organic concentrated feed than in conventionally produced concentrates but there was not so much difference between conventional and organic farmsOrganic farms in levels of pesticide residuesPesticidesresidues in the soil and manure. The observed facts have many implications for the sustainabilitySustainability of organic production. In order to reduce this contamination, practices and regulations of organic production should be revised.
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Due to concerns over negative impacts on insect pollinators, the European Union has implemented a moratorium on the use of three neonicotinoid pesticide seed dressings for mass-flowering crops. We assessed the effectiveness of this policy in reducing the exposure risk to honeybees by collecting 130 samples of honey from bee keepers across the UK before (2014: N = 21) and after the moratorium was in effect (2015: N = 109). Neonicotinoids were present in about half of the honey samples taken before the moratorium, and they were present in over a fifth of honey samples following the moratorium. Clothianidin was the most frequently detected neonicotinoid. Neonicotinoid concentrations declined from May to September in the year following the ban. However, the majority of post-moratorium neonicotinoid residues were from honey harvested early in the year, coinciding with oilseed rape flowering. Neonicotinoid concentrations were correlated with the area of oilseed rape surrounding the hive location. These results suggest mass flowering crops may contain neonicotinoid residues where they have been grown on soils contaminated by previously seed treated crops. This may include winter seed treatments applied to cereals that are currently exempt from EU restrictions. Although concentrations of neonicotinoids were low (<2.0 ng g⁻¹), and posed no risk to human health, they may represent a continued risk to honeybees through long-term chronic exposure.
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New information on the lethal and sublethal effects of neonicotinoids and fipronil on organisms is presented in this review, complementing the previous Worldwide Integrated Assessment (WIA) in 2015. The high toxicity of these systemic insecticides to invertebrates has been confirmed and expanded to include more species and compounds. Most of the recent research has focused on bees and the sublethal and ecological impacts these insecticides have on pollinators. Toxic effects on other invertebrate taxa also covered predatory and parasitoid natural enemies and aquatic arthropods. Little new information has been gathered on soil organisms. The impact on marine and coastal ecosystems is still largely uncharted. The chronic lethality of neonicotinoids to insects and crustaceans, and the strengthened evidence that these chemicals also impair the immune system and reproduction, highlights the dangers of this particular insecticidal class (neonicotinoids and fipronil), with the potential to greatly decrease populations of arthropods in both terrestrial and aquatic environments. Sublethal effects on fish, reptiles, frogs, birds, and mammals are also reported, showing a better understanding of the mechanisms of toxicity of these insecticides in vertebrates and their deleterious impacts on growth, reproduction, and neurobehaviour of most of the species tested. This review concludes with a summary of impacts on the ecosystem services and functioning, particularly on pollination, soil biota, and aquatic invertebrate communities, thus reinforcing the previous WIA conclusions (van der Sluijs et al. 2015).
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Global declines in insects have sparked wide interest among scientists, politicians, and the general public. Loss of insect diversity and abundance is expected to provoke cascading effects on food webs and to jeopardize ecosystem services. Our understanding of the extent and underlying causes of this decline is based on the abundance of single species or taxo-nomic groups only, rather than changes in insect biomass which is more relevant for ecological functioning. Here, we used a standardized protocol to measure total insect biomass using Malaise traps, deployed over 27 years in 63 nature protection areas in Germany (96 unique location-year combinations) to infer on the status and trend of local entomofauna. Our analysis estimates a seasonal decline of 76%, and midsummer decline of 82% in flying insect biomass over the 27 years of study. We show that this decline is apparent regardless of habitat type, while changes in weather, land use, and habitat characteristics cannot explain this overall decline. This yet unrecognized loss of insect biomass must be taken into account in evaluating declines in abundance of species depending on insects as a food source, and ecosystem functioning in the European landscape.
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Growing evidence for global pollinator decline is causing concern for biodiversity conservation and ecosystem services maintenance. Neonicotinoid pesticides have been identified or suspected as a key factor responsible for this decline. We assessed the global exposure of pollinators to neonicotinoids by analyzing 198 honey samples from across the world. We found at least one of five tested compounds (acetamiprid, clothianidin, imidacloprid, thiacloprid, and thiamethoxam) in 75% of all samples, 45% of samples contained two or more of these compounds, and 10% contained four or five. Our results confirm the exposure of bees to neonicotinoids in their food throughout the world. The coexistence of neonicotinoids and other pesticides may increase harm to pollinators. However, the concentrations detected are below the maximum residue level authorized for human consumption (average ± standard error for positive samples: 1.8 ± 0.56 nanograms per gram).
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Neonicotinoid pesticides were first introduced in the mid-1990s, and since then, their use has grown rapidly. They are now the most widely used class of insecticides in the world, with the majority of applications coming from seed dressings. Neonicotinoids are water-soluble, and so can be taken up by a developing plant and can be found inside vascular tissues and foliage, providing protection against herbivorous insects. However, only approximately 5% of the neonicotinoid active ingredient is taken up by crop plants and most instead disperses into the wider environment. Since the mid-2000s, several studies raised concerns that neonicotinoids may be having a negative effect on non-target organisms, in particular on honeybees and bumblebees. In response to these studies, the European Food Safety Authority (EFSA) was commissioned to produce risk assessments for the use of clothianidin, imidacloprid and thiamethoxam and their impact on bees. These risk assessments concluded that the use of these compounds on certain flowering crops poses a high risk to bees. On the basis of these findings, the European Union adopted a partial ban on these substances in May 2013. The purpose of the present paper is to collate and summarise scientific evidence published since 2013 that investigates the impact of neonicotinoids on non-target organisms. Whilst much of the recent work has focused on the impact of neonicotinoids on bees, a growing body of evidence demonstrates that persistent, low levels of neonicotinoids can have negative impacts on a wide range of free-living organisms.
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Neonicotinoid insecticides have come under increasing scrutiny for their impact on non-target organisms, especially pollinators. The current scientific literature is mainly focused on the impact of these insecticides on pollinators and some aquatic insects, leaving a knowledge gap concerning soil invertebrates. This study aimed at filling this gap, by determining the toxicity of imidacloprid and thiacloprid to five species of soil invertebrates: earthworms (Eisenia andrei), enchytraeids (Enchytraeus crypticus), Collembola (Folsomia candida), oribatid mites (Oppia nitens) and isopods (Porcellio scaber). Tests focused on survival and reproduction or growth, after 3–5 weeks exposure in natural LUFA 2.2 standard soil. Imidacloprid was more toxic than thiacloprid for all species tested. F. candida and E. andrei were the most sensitive species, with LC50s of 0.20–0.62 and 0.77 mg/kg dry soil for imidacloprid and 2.7–3.9 and 7.1 mg/kg dry soil for thiacloprid. EC50s for effects on the reproduction of F. candida and E. andrei were 0.097–0.30 and 0.39 mg/kg dry soil for imidacloprid and 1.7–2.4 and 0.44 mg/kg dry soil for thiacloprid. The least sensitive species were O. nitens and P. scaber. Enchytraeids were a factor of 5–40 less sensitive than the taxonomically related earthworm, depending on the endpoint considered. Although not all the species showed high sensitivity to the neonicotinoids tested, these results raise awareness about the effects these insecticides can have on non-target soil invertebrates.
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There is clear evidence for sublethal effects of neonicotinoid insecticides on non-target ecosystem service-providing insects. However, their possible impact on male insect reproduction is currently unknown, despite the key role of sex. Here, we show that two neonicotinoids (4.5 ppb thiamethoxam and 1.5 ppb clothianidin) significantly reduce the reproductive capacity of male honeybees (drones), Apis mellifera. Drones were obtained from colonies exposed to the neonicotinoid insecticides or controls, and subsequently maintained in laboratory cages until they reached sexual maturity. While no significant effects were observed for male teneral (newly emerged adult) body mass and sperm quantity, the data clearly showed reduced drone lifespan, as well as reduced sperm viability (percentage living versus dead) and living sperm quantity by 39%. Our results demonstrate for the first time that neonicotinoid insecticides can negatively affect male insect reproductive capacity, and provide a possible mechanistic explanation formanaged honeybee queen failure and wild insect pollinator decline. The widespread prophylactic use of neonicotinoids may have previously overlooked inadvertent contraceptive effects on non-target insects, thereby limiting conservation efforts.
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Worldwide pollinator declines are attributed to a number of factors, including pesticide exposures. Neonicotinoid insecticides specifically have been detected in surface waters, non-target vegetation, and bee products, but the risks posed by environmental exposures are still not well understood. Pollinator strips were tested for clothianidin contamination in plant tissues, and the risks to honey bees assessed. An enzyme-linked immunosorbent assay (ELISA) quantified clothianidin in leaf, nectar, honey, and bee bread at organic and seed-treated farms. Total glycogen, lipids, and protein from honey bee workers were quantified. The proportion of plants testing positive for clothianidin were the same between treatments. Leaf tissue and honey had similar concentrations of clothianidin between organic and seed-treated farms. Honey (mean±SE: 6.61 ± 0.88 ppb clothianidin per hive) had seven times greater concentrations than nectar collected by bees (0.94 ± 0.09 ppb). Bee bread collected from organic sites (25.8 ± 3.0 ppb) had significantly less clothianidin than those at seed treated locations (41.6 ± 2.9 ppb). Increasing concentrations of clothianidin in bee bread were correlated with decreased glycogen, lipid, and protein in workers. This study shows that small, isolated areas set aside for conservation do not provide spatial or temporal relief from neonicotinoid exposures in agricultural regions where their use is largely prophylactic.
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The bee species Melipona scutellaris Latreille, 1811 (Hymenoptera: Apidae) is native to Brazil and, stingless. In Brazil, stingless bees are responsible for 40% to 90% of tree species pollination, depending on the considered ecosystem. However, their survival has been threatened since the country has been standing out as a big consumer of pesticides. Many of the pesticides used are considered toxic to bees, including imidacloprid. Although the bees are not the target of these substances, they are highly vulnerable to contamination. Thereby, the objective of this study was to establish the mean lethal dose (LD50) and the mean lethal concentration (LC50) of imidacloprid for the M. scutellaris. In order to carry out this experiment, bees were collected and the test was performed according to OECD's protocol (1998a, 1998b), developed for A. mellifera. For the determination of LD50 and LC50, data was analyzed through the Probit method. The topical LD50 established in this study was 2.41 ng/ bee for 24 hours and 1.29 ng/bee for 48 hours. The oral LC50 was 2.01 ng i.a./mu L for 24 hours and 0.81 ng i.a./mu L for 48 hours. Thus, it is important to establish management methods which take this higher susceptibility into account to protect native species.
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The package ftdistrplus provides functions for tting univariate distributions to different types of data (continuous censored or non-censored data and discrete data) and allowing different estimation methods (maximum likelihood, moment matching, quantile matching and maximum goodness-of-fit estimation). Outputs of fitdist and fitdistcens functions are S3 objects, for which speci c methods are provided, including summary, plot and quantile. This package also provides various functions to compare the fit of several distributions to the same data set and can handle to bootstrap parameter estimates. Detailed examples are given in food risk assessment, ecotoxicology and insurance contexts. Download at http://www.jstatsoft.org/article/view/v064i04
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This is the author accepted manuscript. It is under infinite embargo pending publication of the final version.
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Over half of the European landscape is under agricultural management and has been for millennia. Many species and ecosystems of conservation concern in Europe depend on agricultural management and are showing ongoing declines. Agri-environment schemes (AES) are designed partly to address this. They are a major source of nature conservation funding within the European Union (EU) and the highest conservation expenditure in Europe. We reviewed the structure of current AES across Europe. Since a 2003 review questioned the overall effectiveness of AES for biodiversity, there has been a plethora of case studies and meta-analyses examining their effectiveness. Most syntheses demonstrate general increases in farmland biodiversity in response to AES, with the size of the effect depending on the structure and management of the surrounding landscape. This is important in the light of successive EU enlargement and ongoing reforms of AES. We examined the change in effect size over time by merging the data sets of 3 recent meta-analyses and found that schemes implemented after revision of the EU's agri-environmental programs in 2007 were not more effective than schemes implemented before revision. Furthermore, schemes aimed at areas out of production (such as field margins and hedgerows) are more effective at enhancing species richness than those aimed at productive areas (such as arable crops or grasslands). Outstanding research questions include whether AES enhance ecosystem services, whether they are more effective in agriculturally marginal areas than in intensively farmed areas, whether they are more or less cost-effective for farmland biodiversity than protected areas, and how much their effectiveness is influenced by farmer training and advice? The general lesson from the European experience is that AES can be effective for conserving wildlife on farmland, but they are expensive and need to be carefully designed and targeted.
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