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A Review of Boron Toxicity in Insects With an Emphasis on Termites

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Abstract

Managing urban pests with "environmentally-friendly" com­ pounds has gained importance in recent years with the global deregistration of persistent organochlorine insecticides. Boron compounds, especially boric acid, zinc borate, and disodium octaborate tetrahydrate, are considered excellent options for preserving lumber from insect attack as well as decay by fungi and bacteria. Remedial borate applications are used primarily to treat cockroach and flea infestations but have also achieved recent popularity as wood treat­ ments to protect timber from colonization by subterranean termites. The goal of this review is to provide a synthesis of the research on the toxicity of boron in insects with a specific focus on termites and urban pests.
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... Although the scientific community has shown increasing interest in exploring the biological effects of BCCs [6,9], many people remain cautious about their use in many applications. This is likely linked to the widespread information about boron compounds, essentially about boric acid with regard to its ability to contaminate soils and then be toxic to plants [1] when widely used for effectively controlling the plagues of cockroaches due to its toxicity towards some insects (which is considered a difficult task due to the ability of insects to adapt and resist multiple situations mitigating their life) [10,11]. ...
... In animals, BCCs induce high toxicity in some species of invertebrates, particularly in some nematodes [36], insects [10,11], and spiders [37]. Meanwhile, only poor data exist about boron toxicity in marine invertebrates [38,39]. ...
... The toxicity to some phyla in the Kingdom Eukarya can be used for controlling vectors for infectious diseases or poisoning species for humans. The design of BCCs for protists, insects and spiders is poorly approached [11,29] despite natural BCCs having been identified as efficient compounds generated by evolution [22,49]. The toxicity of BCCs isolated from plants can be useful at least in infection, inflammatory and cardiovascular therapy research [49,50]; this can be supported if clear mechanisms of action and dosages are established. ...
Article
Background Despite the historical employment of boron-containing compounds (BCCs) with medicinal purposes, the reported cases of BCC toxicity in humans during the twentieth-century drived us towards a “boron-withdrawal” period. Fortunately, the use of boric acid for specific purposes remains, and the discovery of natural BCCs with biological action attractive for therapeutic purposes as well as the introduction of some new BCCs for clinical use has reactivated the interest in studying the properties of these BCCs. Methods We carried out a structured search of bibliographic databases for scientific peerreviewed research literature regarding boron toxicity and linked that information to that of BCCs in drug design and development. A deductive qualitative content analysis methodology was applied to analyse the interventions and findings of the included studies using a theoretical outline. Results This review recapitulates the following on a timeline: the boron uses in medicine, the data known about the toxicological profiles of some BCCs, the pharmacological properties of some BCCs that are employed in cancer and infectious disease therapies, and the known properties of BCCs recently introduced into clinical assays as well as the identification of their structure-activity relationships for toxicity and therapeutic use. Then, we discuss the use of new approaches taking advantage of some toxicological data to identify potent and efficient BCCs for prevention and therapy while limiting their toxic effects. Conclusion Data for boron toxicity can be strategically used for boron-containing drug design.
... Currently, modern wood preservatives can be characterized into fi ve groups: containing boron, CCA (restricted use and being phased out), dissolved copper based (primary replacements for CCA), copper suspension based (micronized or fi nely ground copper particles suspended in water) and carbon based (containing little or no metals) (Gentz and Grace, 2006;Cushman, 2009;Ismayati, et al., 2011). The mode of action of boron include the rapid esterifi cation of borates with molecules of biological significance (Gentz and Grace, 2006), for copperbased preservatives the oxidizing of pro teins, enzymes and lipids (Freeman and McIntyre, 2008) and for products containing imidacloprid, a nerve poison that affects the acetylcholine binding sites called nicotinergic receptors (Ramakrishnan et al., 2000). ...
... Currently, modern wood preservatives can be characterized into fi ve groups: containing boron, CCA (restricted use and being phased out), dissolved copper based (primary replacements for CCA), copper suspension based (micronized or fi nely ground copper particles suspended in water) and carbon based (containing little or no metals) (Gentz and Grace, 2006;Cushman, 2009;Ismayati, et al., 2011). The mode of action of boron include the rapid esterifi cation of borates with molecules of biological significance (Gentz and Grace, 2006), for copperbased preservatives the oxidizing of pro teins, enzymes and lipids (Freeman and McIntyre, 2008) and for products containing imidacloprid, a nerve poison that affects the acetylcholine binding sites called nicotinergic receptors (Ramakrishnan et al., 2000). By some estimates, the use of wood preservatives is 75% of the total poundage of pesticides used in North America . ...
... 8 Using borates such as borax and boric acid as toxicant would be desirable given their low mammalian toxicity 9 and presumed lack of insect resistance, compared to the organic insecticides. 8 Boratebased insecticides have been used to kill cockroaches, 10 termites, 11 and flies. [12][13][14] Lethal and sublethal effects of boric acid were observed in Galleria mellonella (L.) (Lepidoptera: Pyralidae) when exposed to a wide range of concentrations. ...
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Background: In recent years, there has been interest in low-cost, reduced-risk materials that could be used for attract-and-kill of the invasive pest, spotted-wing Drosophila, Drosophila suzukii. This pest causes heavy economic damage to soft-skinned fruits in many countries. In this study, we evaluated physiological and behavioral effects of adding either borax, boric acid, or sodium chloride to diluted Concord grape juice (DGJ), a material that is attractive to adult D. suzukii. Results: Results showed that the addition of borax, sodium chloride and boric acid did not significantly affect the response of adult D. suzukii, relative to DGJ alone. Increases in concentrations (to 5% and 10%) of borax, sodium chloride and boric acid were correlated with decreased ingestion of materials. Mortality of males and females was almost 100% with lower concentrations (1% and 5%) of borax and boric acid within 72 h. The higher concentrations of sodium chloride (5% and 10%) resulted in 100% mortality of both sexes within 72 h. There was no significant effect of chemicals on the number of crop contractions of flies when fed for 4h. Conclusions: This study suggests that some substances such as boric acid and borax may act as toxicants without influencing the behavioral response of D. suzukii.
... In practical use, boron is used as a wood preservative to prevent attack by decay fungi and certain insects including termites and wood-boring beetles, as well as in insecticide formulations against urban insects, such as cockroaches and fleas. Various boron formulations alter behavioral and physiological responses of the termite Coptotermes formosanus (Gentz and Grace, 2006). For example, termite damage is lower in boratetreated lumber than in untreated wood Tsuboda et al., 2006). ...
Article
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Flower thinning is necessary for crop production in various orchards. The effects of various ingredients of Koduri–Plus, an eco–friendly flower thinning formulation (FTF), were determined on the major pollination insect Apis mellifera. Three different FTFs, a mixture of 0.7% zinc and 1.5% manganese (A), a mixture of 0.7% zinc and 2.0% boron (B), a mixture of 2.0% seaweed extract (C), and lime sulfur solution were examined by measuring the contact and oral toxicities against adult worker bees. Both direct spray and oral ingestion of all three 1% FTF solutions did not cause any lethal effects for workers based on 72 h observation, but treatment with 1% lime sulfur solution increased worker mortality. Oral ingestion of FTF A and FTF C did not inhibit acetylcholinesterase (AChE) activity of workers at 24 h after treatment, but was slightly decreased by FTF B treatment. However, oral ingestion of the organophosphate pesticide dichlorvos or lime sulfur solutions significantly inhibited AChE activities. Our results suggest that manganese and seaweed extract of FTFs were not toxic for honeybees, in terms of contact and ingestion. Therefore, newly developed FTFs can be used to improve flower thinning activity without any detrimental effects on pollinating insects
... In order to achieve an increased protection against pests, formulation improvements should take into account several features of the target substrate [22]. In the case of wool panels, boron behaviour after application could be affected by the chemical-physical properties of both wool and additional materials that make up the structure of the panels [16]. ...
Article
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In this study the resistance opposed to Tineola bisselliella larvae by a commercial sheep-wool panel incorporating borate salts was determined under laboratory conditions. The susceptibility of clothes moth larvae to different concentrations of disodium octaborate tetrahydrate (DOT) incorporated in pure wool was also determined. The commercial wool panel showed a remarkable resistance to moth attack compared with pure untreated wool, and the damage to panel samples was limited to their surface. As a result of bioassays exposing larvae to pure wool treated with DOT, a concentration dependent effect was observed, achieving a good efficacy at an application rate between 40–100 mg/mL. This study highlights the need to protect wool-based construction material with appropriate insecticidal (antifeedant or repellent) substances and supports the development of eco-sustainable solutions.
... Omurgasız canlılar üzerinde görülen ve çalışmamızda elde ettiğimiz LC 50 değerine en yakın değer Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae) işçileri üzerinde borik asit uygulaması sonucunda elde edilen 721 mg/kg (721 ppm) değeridir [17] Gammarid bireylerinde tespit edilen ölümlerin nedeni [18][19] anlaşılmaktadır. Ayrıca, Bauer vd. ...
... However, due to its high mammalian and environmental toxicity, it has been banned by EU legislation in 2003 and is being phased out also by other countries. Presently, anti-termite wood preservative treatments include those containing boron (Gentz and Grace 2006;Nami Kartal et al. 2007;Kose et al. 2011;Han et al. 2012;Li et al. 2012), copper and/or zinc (Tascioglu and Tsunoda 2010;Wu et al. 2012;Maistrello et al. 2012a;Akhtari and Nicholas 2013). More treatments are being discovered and tested, such as those derived from plants (Kartal et al. , 2012(Kartal et al. , 2013. ...
Chapter
A standard is a technical document approved by a recognized certification body at national or international level, which defines and unifies the characteristics and specifications of a process, product or service, to ensure quality and safe, reliable performances in respect to environment. The use of international standards allows to remove barriers to world trade, and their importance is particularly recognized in the field of wood technology, to guarantee that preservatives are effective in protecting wood from biotic degradation agents, such as termites. In the European Union, the USA, Australia and Japan, the existing standard norms to test efficacy against termites are exclusively related to subterranean species (Rhinotermitidae). Due to the great differences in biological features, these standards are not suitable for drywood termites (Kalotermitidae) that, on the other hand, are increasingly indicated as serious wood pests, worldwide. This chapter aims at filling this gap by outlining the differences in biology, ecology and behaviour of the two types of termites and their importance as invasive pests, describing the importance and features of standard norms and reviewing the available standards for wood protection against termites. Finally, a proposal for a standard protocol is presented, specifically developed to determine the efficacy of preventive wood treatments on drywood termites.
... (103) and M. darwiniensis are relatively borate-tolerant (104). Boron is known to affect some species of protozoa in the gut of lower termites (105), and also inhibits a number of metabolic processes although the main mode of action remains unclear (106,107). ...
Chapter
The management of termite risk for the protection of timber structures mainly from subterranean termites, are discussed. Inedible wood may be produced from naturally durable timber, impregnation using extractives from naturally durable wood, wood preservatives such as preservative oils, copper-based preservatives, pyrethroids and other organic insecticides, modified wood and preserved wood composites. These measures should be used in conjunction with a whole-of-structure approach that protects buildings using barriers such as graded particles that termites cannot penetrate, resistant sheet materials, or soil treatments. Traditional and electronic detection methods are available for detecting termite activity in a structure, which then allows additional control methods such as baiting and dusting to be introduced. An understanding of the termite hazard and their habits will allow for improved building design and maintenance regimes that will mitigate the risk of termite attack.
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Book
For the first time, the whole field of organoboronic acids is presented in one comprehensive handbook. Professor Dennis Hall, a rising star within the community, covers all aspects of this important substance class, including applications in chemistry, biology and medicine. Starting with an introduction to the structure, properties, and preparation of boronic acid derivatives, together with an overview of their reactions and applications, the book goes on to look at metal-catalyzed borylation of alkanes and arenas, coupling reactions and rhodium-catalyzed additions of boronic acids to alkenes and carbonyl compounds. There follows chapters on copper-promoted C-O and C-N cross-coupling of boronic acids, recent applications in organic synthesis, as well as alpha-haloalkylboronic esters in asymmetric synthesis. Later sections deal with cycloadditions, organoboronic acids, oxazaborolidines as asymmetric inducers, and boronic acid based receptors and sensors. The whole is rounded off with experimental procedures, making this invaluable reading for organic, catalytic and medicinal chemists, as well as those working in organometallics. © 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. All rights reserved.
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Comparative toxicity of three boron compounds, boric acid (BA), disodium tetraborate decahydrate (DTD) and disodium octaborate tetrahydrate (DOT), against a lower termite, Coptotermes formosanus Shiraki, was investigated. Residual nature in termite body and the effect on respiration were also evaluated using boric acid as a substrate. Among three compounds BA performed best, showing the oral LD99 . 16 days value as approximately 930 mu g/g termite and 136 mu g/g termite (lethal accumulate). Approximately 20% of the ingested boric acid remained in the termite's body after more than 16 days. Ingestion of wood meal treated with BA at 20 kg/m(3) caused a 20% reduction of respiratory volumes, even when no mortality was observed. These results suggested that a relative amount of ingested boron compounds remained within the termite bodies and expressed their termiticidal performance by various physiological effects including obstruction of respiration.