Philippe Juneau

• PhD
• Professor (Full) at University of Quebec in Montreal

Nanoplastics (NPs) and neonicotinoids are common pollutants in aquatic ecosystems. Although their co-occurrence is expected in multiple environments, studies assessing their combined effects are still limited. This toxicological assessment investigated the potential effects of polystyrene NPs (PSNPs), clothianidin (CLO), and their mixtures on four...

The phytotoxicity and removal of atrazine and S-metolachlor in sterile duckweed systems were estimated in this study. Herbicides were added at environmentally relevant ranges: 0–400 µg/L for atrazine or 0–200 µg/L for S-metolachlor in systems with Spirodela polyrhiza or Lemna minor. Toxicity biomarkers, i.e., changes in plant biomass, surface area,...

We compared the ability of one emergent (Sagittaria montevidensis), two floating (Salvinia minima and Lemna gibba), and one heterophyllous species (Myriophyllum aquaticum) to simultaneously remove sulfamethoxazole, sulfadiazine, ciprofloxacin, enrofloxacin, norfloxacin, levofloxacin, oxytetracycline, tetracycline, doxycycline, azithromycin, amoxici...

Elsevier Journal of Hazardous Materials Available online 2 April 2024, 134202 In Press, Journal Pre-proofWhat’s this? Journal of Hazardous Materials Emerging Threat: Antimicrobial Resistance Proliferation During Epidemics — A Case Study of the SARS-CoV-2 Pandemic in South Brazil Author links open overlay panelRaizza Zorman Marques a 1, Keite da Sil...

The mechanisms of cadmium toxicity to cyanobacterial photosynthesis have been extensively studied, but the response mechanisms to combinations of different cadmium concentrations and different light intensities are not yet well understood. The two principal objectives of the present work were to: 1) study the short term (5 h) toxic effects of cadmi...

This study aimed (1) to assess the ability of collembolans Folsomia candida to avoid soils contaminated with three seed dressing insecticides imidacloprid, clothianidin, and fipronil; (2) to assess the effects of the insecticides on collembolans’ locomotion behavior; (3) to check if changes in the locomotion behavior would explain the avoidance/pre...

Citation: Kitamura, R.S.A.; Fusaro, T.; Marques, R.Z.; Brito, J.C.M.; Juneau, P.; Gomes, M.P. The Use of Aquatic Macrophytes as a Nature-Based Solution to Prevent Ciprofloxacin Deleterious Effects on Microalgae. Water 2023, 15, 2143. https:// Abstract: Macrophytes have demonstrated excellent potential for the removal of pharmaceuticals from water....

In aquatic ecosystems, microalgae are exposed to light fluctuations at different frequencies due to daily and seasonal changes. Although concentrations of herbicides are lower in Arctic than in temperate regions, atrazine and simazine, are increasingly found in northern aquatic systems because of long-distance aerial dispersal of widespread applica...

Water contamination by pharmaceuticals is a global concern due to their potential negative effects on aquatic ecosystems and human health. This study examined the presence of three repositioned drugs used for COVID-19 treatment: azithromycin (AZI), ivermectin (IVE) and hydroxychloroquine (HCQ) in water samples collected from three urban rivers in C...

Citation: Kochi, L.Y.; Kitamura, R.S.A.; Rocha, C.S.; Brito, J.C.M.; Juneau, P.; Gomes, M.P. Synergistic Removal of Ciprofloxacin and Sulfamethoxazole by Lemna minor and Salvinia molesta in Mixed Culture: Implications for Phytoremediation of Antibiotic-Contaminated Water. Water 2023, 15, 1899. https:// Abstract: Aquatic macrophytes have been used f...

We investigated physiological responses of Lemna minor plants and their capacity to remove tenofovir (TNF; 412 ng l−1), lamivudine (LMV; 5428 ng l−1) and/or efavirenz (EFV; 4000 ng l−1) from water through phytoremediation. In addition, the toxicological safety of water contaminated with these drugs after treatment with L. minor plants to photosynth...

Pesticides leaching and run-off to nearby freshwater sources are a major ecological concern. The emergence of herbicide-resistant weeds led to the increased usage of fomesafen, a diphenyl ether herbicide inhibiting protoporphyrinogen oxidase (PPO). This recent rise in demand and use for this molecule invariably increases the chance of this herbicid...

The intensive global use of glyphosate has led to the evolution of glyphosate resistant (GR) weed species, including the economically damaging horseweed (Conyza sumatrensis). We evaluated the glyphosate resistance mechanisms of C. sumatrensis. While 5-enolpyruvylshikimate-3-phosphate synthase activity was similar between the glyphosate resistant (G...

The intensive global use of glyphosate has led to the evolution of glyphosate resistant (GR) weed species, including the economically damaging horseweed (Conyza sumatrensis). We evaluated the glyphosate resistance mechanisms of C. sumatrensis. While 5-enolpyruvylshikimate-3-phosphate synthase activity was similar between the glyphosate resistant (G...

Enrofloxacin (Enro) is often detected in soil and animal manure used for crop production and phytotoxic responses have been observed in plants grown under antimicrobial presence. In the present paper, we investigated the effects of the presence of Enro in soils (1.9 mg kg-1) and manure (50.4 mg kg-1) in growth and flower production of calla lily pl...

Polar ecosystems play an important role in global primary production. Microalgae have adaptations that enable them to live under low temperature environments where irradiance and day length change drastically. Their adaptations, leading to different ecophysiological characteristics relative to temperate species, could also alter their sensitivity t...

Approximately half of the global annual production of wastewater is released untreated into aquatic environments, which results in worldwide organic matter pollution in urban rivers, especially in highly populated developing countries. Nonetheless, information on microbial community assembly and assembly‐driving processes in organic matter‐polluted...

Aminomethylphosphonic acid (AMPA) has been proposed to interfere with chlorophyll biosynthesis in photoautotrophic organisms – which may explain its greater toxicity to plants in relation to animals. By using the aquatic macrophyte Lemna minor, we investigated the AMPA toxicity and its effects on chlorophyll biosynthesis. Environmentally relevant c...

We investigated the occurrence and risk assessment of three anti-HIV drugs [(tenofovir (TNF), lamivudine (LMV) and efavirenz (EFV)] in urban rivers from Curitiba (Brazil), as well as the individual and combined effects of their environmental representative concentrations on the freshwater periphytic species Synechococcus elongatus (Cyanobacteria) a...

This study investigated the occurrence and risk assessment of ten pharmaceutical products and two herbicides in the water of rivers from the Doce river watershed (Brazil). Of the 12 chemicals studied, ten (acyclovir, amoxicillin, azithromycin, ciprofloxacin, enrofloxacin, fluoxetine, erythromycin, sulfadiazine, sulfamethoxazole, glyphosate and amin...

Clarifying mechanisms underlying the ecological succession of gut microbiota is a central theme of gut ecology. Under experimental manipulations of zebrafish hatching and rearing environments, we test our core hypothesis that the host development will overwhelm environmental dispersal in governing fish gut microbial community succession due to host...

We have studied the isolated and combined effects of metals (Fe and Mn) and NaCl the on growth, physiology, and metal-uptake capacity of two photosynthetic periphytic species-Synechococcus elongatus (Cyanobacteria) and Chlorococcum infusionum (Chlorophyta)-isolated from an impacted area of the Rio Doce River (Brazil) after the Fundão dam collapse....

Both low temperature and nitrogen starvation caused chlorosis of cyanobacteria. Here, in this study, for the first time, we compared the effects of low temperature, nitrogen starvation, and their combination on the photosynthesis and metabolites of a thermophilic cyanobacterium strain, Thermosynechococcus E542. Under various culture conditions, the...

Shift of phytoplankton niches from low to high latitudes has altered their experienced light exposure durations and temperatures. To explore this interactive effect, the growth, physiology, and cell compositions of smaller Alexandrium minutum and larger A. catenella, globally distributed toxic red tide dinoflagellates, were studied under a matrix o...

Norfloxacin is one of the widely used antibiotics, often detected in aquatic ecosystems, and difficultly degraded in the environment. However, how norfloxacin affects the photosynthetic process of freshwater phytoplankton is still largely unknown, especially under varied light conditions. In this study, we investigated photosynthetic mechanisms of...

Environmental Molecular Microbiology (EMM) is a core course cluster for students majoring in environmental engineering. To help students learn the EMM courses, we developed a three-stage teaching approach to deliver EMM courses in a systematic manner: prerequisite course and survey studies; course cluster teaching; and feedback and improvement. In...

Harmful algal blooms of cyanobacteria (CyanoHABs) can lead to the release of potent toxins that can seriously affect ecosystem integrity. Some freshwater watersheds are particularly at risk considering the threats to already imperiled wildlife. The consumption of tainted drinking water and contaminated food also raises concerns for human health. In...

An increasing production and use of titanium dioxide nanoparticles (TiO2 NPs) pose a huge threat to phytoplankton since they are largely released into aquatic environments, which represent a sink for TiO2 NPs. However, toxicity and protective mechanisms of cyanobacteria in response to TiO2 NPs remain elusive. Here we investigated toxic effects of t...

Antibiotics and metals introduced during manure application are believed to be the major drivers of the bloom and spread of antibiotic resistance genes (ARGs) and metal resistance genes (MRGs) in agricultural environments. However, the coexistence of multidrug resistance (MDR) and metal resistance and the effects of manure application on the coexis...

The effects of the photocatalytic toxicity of titanium dioxide nanoparticle (nano-TiO2) on phytoplankton are well understood. However, as UV light intensity decreases sharply with the depth of the water column, the effects of nano-TiO2 itself on deeper water phytoplankton, such as green algae, need further research. In this research, we investigate...

With rapid global urbanization, massive anthropogenic inputs of organic matter and inorganic nutrients are resulting in severe pollution of urban rivers and consequently altering the structure and function of their aquatic microbial communities. In contrast to nutrient-induced eutrophication of freshwaters, water blackening and odorization of urban...

There is growing concern among health institutions worldwide to supply clean water to their populations, especially to more vulnerable communities. Although sewage treatment systems can remove most contaminants, they are not efficient at removing certain substances that can be detected in significant quantities even after standard treatments. Consi...

We investigated individual and combined effects of environmentally representative concentrations of amoxicillin (AMX; 2 μg l⁻¹), enrofloxacin (ENR; 2 μg l⁻¹), and oxytetracycline (OXY; 1 μg l⁻¹) on the aquatic macrophyte Lemna minor. While the concentrations of AMX and ENR tested were not toxic, OXY decreased plant growth and cell division. OXY ind...

Les cyanotoxines présentes dans l’environnement menacent l’intégrité des écosystèmes aquatiques et la santé humaine. Dans un contexte où les changements climatiques sont susceptibles de favoriser les efflorescences cyanobactériennes, il nous apparaît nécessaire de mettre à jour nos connaissances sur ce sujet. Cette revue de littérature synthétise l...

Elevated nitrate in the environment inhibits sulfate reduction by important microorganisms of sulfate-reducing bacteria (SRB). Several SRB may respire nitrate to survive under elevated nitrate, but how SRB that lack nitrate reductase survive to elevated nitrate remains elusive. To understand nitrate adaptation mechanisms, we evolved 12 populations...

The poorly understood filamentous cyanobacterium Pseudanabaena is commonly epiphytic on Microcystis colonies and their abundances are often highly correlated during blooms. The response and adaptation of Microcystis to iron limitation have been extensively studied, but the strategies Pseudanabaena uses to respond to iron limitation are largely unkn...

Herbicides are one of the major causes of aquatic environment degradation. Among herbicides, concerns on the fate and environmental occurrence of glyphosate (N-(phosphonometyl)glycine), the most used herbicide worldwide, have greatly increased over the past decade. However, due to its short half-life, the co-occurrence of glyphosate and its by-prod...

The mechanisms of cadmium toxicity to cyanobacterial photosynthesis have been extensively studied, but the response mechanisms to combinations of different cadmium concentrations and different light intensities are not yet well understood. The two principal objectives of the present work were to: 1) study the short term (5 h) toxic effects of cadmi...

The co-occurrence of aquatic contaminants, such as antibiotics and herbicides, has motivated investigations into their interactive effects on aquatic organisms. We examined the combined effects of environmental concentrations of the antibiotic Enrofloxacin (Enro; 0-2.25 μg l-1) and Roundup OriginalDI (Roundup®; 0-0.75 μg active ingredient l-1), a g...

Riparian buffer strips (RBS) are encouraged to control agricultural diffuse pollution. In Quebec Province, Canada, a policy promotes 3‐m‐wide RBS. Abiding farmers minimally maintain herbaceous vegetation, but nutrient retention efficiency could be improved with woody biomass. This work aimed to assess if fast‐growing willows (Salix miyabeana Seemen...

Bacterioplankton are both primary producers and primary consumers in aquatic ecosystems, which were commonly investigated to reflect environmental changes, evaluate primary productivity, and assess biogeochemical cycles. However, there is relatively less understanding of their responses to anthropogenic disturbances such as constructions of dams/tu...

Cladocerans feed on a variety of phytoplankton food sources, which are variable across space and time. Different phytoplankton groups represent different nutritional quality to Daphnia magna (Straus) due to differences in their Redfield stoichiometry or digestibility. We used chlorophyll fluorescence to directly measure phytoplankton group quantity...

Mesotrione, an herbicide increasingly found in aquatic systems due to its increased application frequency in corn fields, is an inhibitor of the p-hydroxyphenylpyruvate dioxygenase (HPPD), a key enzyme for plastoquinone-9, α-tocopherol and indirectly for carotenoid biosynthesis. The direct effect of mesotrione on plastoquinone-9 and α-tocopherol sy...

The 16S rRNA gene is one of the most commonly used molecular markers for estimating bacterial diversity during the past decades. However, there is no consistency about the sequencing depth (from thousand to millions of sequences per sample), and the clustering methods used to generate OTUs may also be different among studies. These inconsistent pre...

In situ remediation employing organohalide-respiring bacteria represents a promising solution for cleanup of persistent organohalide pollutants. The organohalide-respiring bacteria conserve energy by utilizing H2or organic compounds as electron donors and organohalides as electron acceptors. Reductive dehalogenase (RDase), a terminal reductase of t...

Residual glyphosate from glyphosate based herbicides (GBH) are ubiquitously detected in streams draining agricultural fields, and may affect phytoplankton communities present in these ecosystems. Here, the effects of the exposure (96 h) of a phytoplankton community collected in an agricultural stream to various glyphosate concentrations (1, 5, 10,...

The use of glyphosate-based herbicides in agriculture has increased steadily since the mid 90's and there is now evidence of glyphosate leaching and contamination of aquatic ecosystems. The aim of this study was to evaluate the effects of a glyphosate-based herbicide (Factor 540(®)) on growth and photosynthetic capacity of algae and cyanobacteria....

HIGHLIGHTS We reviewed the interaction between light, temperature and herbicides on algal and cyanobacterial physiology. Temperature is the main factor affecting herbicide toxicity to algae and cyanobacteria. Changes in light environment may modulate the effects of photosynthesis-targeting herbicides. Important interactions between climatic parame...

Aqueous glyphosate transport across narrow riparian buffer strips (RBS) is little studied. • RBS efficiency for reducing glyphosate and AMPA leaching to streams is limited. • Spontaneous herbaceous vegetation RBS is as efficient as Salix plantations. • Glyphosate, present in runoff after a year, suggest unexpected persistence. • RBS may favor glyph...

We studied the physiological mechanisms involved in the deleterious effects of a glyphosate-based herbicide (Factor® 540) on photosynthesis and related physiological processes of willow (Salix miyabeana cultivar SX64) plants. Sixty-day-old plants grown under greenhouse conditions were sprayed with different rates (0, 1.4, 2.1, and 2.8 kg a.e ha⁻¹)...

Iron deficiency has been considered one of the main limiting factors of phytoplankton productivity in some aquatic systems including oceans and lakes. Concomitantly, solar ultraviolet-B radiation has been shown to have both deleterious and positive impacts on phytoplankton productivity. However, how iron-deficient cyanobacteria respond to UV-B radi...

Atrazine is an herbicide frequently detected in watercourses that can affect the phytoplankton community, thus impacting the whole food chain. This study aims, firstly, to measure the sensitivity of monocultures of the green alga Scenedemus obliquus and toxic and non-toxic strains of the cyanobacteria Microcystis aeruginosa before, during and after...

A simple first-principles mathematical model is developed to predict the performance of a micro photosynthetic power cell ( μ PSC), an electrochemical device which generates electricity by harnessing electrons from photosynthesis in the presence of light. A lumped parameter approach is used to develop a model in which the electrochemical kinetic ra...

The growing interest for monitoring the quality of water has triggered the need of fast, portable and cheap detection systems. To answer this problematic, we developed a lab on a chip for herbicide detection based on micro algal photosynthesis. A blue organic light-emitting diode is used as the excitation source while the resulting algae luminescen...

The integration of optical source with microfluidics leads to promising low-cost, rapid and sensitive lab-on-a-chip analytical systems. This work deals with the optimization of the electrochemical sensors and the dedicated organic light-emitting diode (OLED) for the monitoring of herbicides though algal photo synthetic activities disturbances. Vari...

A simple first-principles mathematical model is developed to predict the performance of a micro photosynthetic power cell (?PSC), an electrochemical device which generates electricity by harnessing electrons from photosynthesis in the presence of light. A lumped parameter approach is used to develop a model in which the electrochemical kinetic rate...

Since the emergence of microfluidic platforms sensors integration has been a major challenge. With the advances in miniaturization of these platforms, there is a need for solutions to integrate various optical components in order to build sensors, which will offer different detection characteristics such as several emission and sensing wavelengths....

We investigated the physiological responses of Lemna minor plants exposed to glyphosate. The deleterious effects of this herbicide on photosynthesis, respiration, and pigment concentrations were related to glyphosate-induced oxidative stress through hydrogen peroxide (H2O2) accumulation. By using photosynthetic and respiratory electron transport ch...

The present work was dedicated to the development of a lab-on-chip device for water toxicity analysis and more particularly herbicide detection in water. It consists in a portable system for on-site detection composed of three-electrode electrochemical microcells, integrated on a fluidic platform constructed on a glass substrate. The final goal is...

Zinc pollution of freshwater aquatic ecosystems is a problem in many countries, although its specific effects on phytoplankton may be influenced by other environmental factors. Light intensity varies continuously under natural conditions depending on the cloud cover and the season, and the response mechanisms of cyanobacteria to high zinc stress un...

Microcystis sp., especially in its colonial form, is a common dominant species during cyanobacterial blooms in many iron-deficient water bodies. It is still not entirely clear, however, how the colonial forms of Microcystis acclimate to iron-deficient habitats, and the responses of unicellular and colonial forms to iron-replete and iron-deficient c...

Since the emergence of microfluidic platforms, optical sensor integration has been a major challenge. With the advances in miniaturization of these platforms, there is a need of solutions to integrate various optical components in order to build sensors, which will offer different detection characteristics such as several emission and sensing wavel...

Devices such as solar and fuel cells have been studied for many decades and noticeable improvements have been achieved. This paper proposes a Micro Photosynthetic Power Cell (μPSC) as an alternative energy-harvesting device based on photosynthesis of blue-green algae. The effect of important biodesign parameters on the performance of the device, su...

A portable system to monitor water quality in both developed and developing countries is highly required. Currently, there is no commercial test available to satisfy this demand, as only accredited laboratories can perform such evaluations. Miniaturization of analytical instrumentation is one of the dominant trends within the chemical and biologica...

The development of new nanomaterial like carbon nanotubes, graphene and nanowires brings new possibilities to existing technologies. With the emergence of transparent electrode based on these materials, we could imagine new type of sensors, which combines transparency and flexibility. Silver nanowire transparent electrodes are currently transformin...

The strong biological production of estuarine intertidal flats is mainly supported by benthic diatoms in temperate areas. Their photosynthetic productivity is largely driven by changes in light intensity and temperature at the surface of sediment flats during emersion. The impact of an increase in salinity of the upper-layer sediment pore-water dur...

Accumulated sevidence suggests that reactive oxygen species (ROS) and plant hormone signaling pathways form an integrated network that regulates plant growth, development, and their responses to environmental factors. This network involves plant hormones and ROS, which are intrinsically interlinked in plant biology and development, as well as in st...

Norflurazon (Nf) and fluridone (Fd) are phytoene desaturase inhibitor herbicides that are widely used for the control of grasses and invasive aquatic weeds, respectively. These herbicides enter aquatic environments where they can negatively affect non-target plant species (e.g. algae). Their toxicity towards algae may be modified by abiotic factors s...

We investigated the effects of leaf color change in the fall on photosynthetic production and nitrogen resorption. Seedlings of Acer platanoides L. and A. saccharum Marsh. were grown in a shade house for 5 months in either 21 % (intermediate light, M) or 4.9 % (low light, L) of incident irradiance. After this period, a subset of the intermediate-li...

It is generally claimed that glyphosate kills undesired plants by affecting the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) enzyme, disturbing the shikimate pathway. However, the mechanisms leading to plant death may also be related to secondary or indirect effects of glyphosate on plant physiology. Moreover, some plants can metabolize glyp...

An autonomous electrochemical biosensor with three electrodes integrated on the same silicon chip dedicated to the detection of herbicides in water was fabricated by means of silicon-based microfabrication technology. Platinum (Pt), platinum black (Pt Bl), tungsten/tungsten oxide (W/WO3) and iridium oxide (Pt/IrO2) working ultramicroelectrodes were...

Lake thermocline depth is likely to be altered with climate change. We assessed the response of crustacean zooplankton biomass and productivity to an experimental whole-lake manipulation of thermocline depth. Weekly sampling occurred in Experimental and Reference years and responses were assessed with a before–after-control– impact design. While on...

Export Date: 18 October 2014

Les fertilisants, les pesticides et l’érosion des terres agricoles affectent les écosystèmes aquatiques. Depuis longtemps, le gouvernement du Québec recommande l’instauration et la végétalisation de bandes riveraines à titre de phytotechnologie assainissante. Sachant cela, leur faible adoption par les agriculteurs soulève un problème de politique p...