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The high water solubility and ecotoxicity of thiamethoxam (TMX) is a potential hazard to ecosystems and human health. Here, a strain of Bacillus cereus with high TMX degradation activity was isolated from the sediment of the A2O process in the wastewater treatment plant and was able to utilize TMX as its sole carbon source. Under different environmental conditions, the degradation efficiency of TMX by Bacillus cereus -S1 (strain S1) ranged from 41.0% to 68.9% after 216 h. The optimum degradation conditions were DO = 3.5 mg/L and pH 9.0. The addition of an appropriate carbon-to-nitrogen ratio could accelerate the degradation of TMX. A plausible biodegradation pathway has been proposed based on the identified metabolites and their corresponding degradation pathways. TMX can be directly converted into Clothianidin (CLO), TMX-dm-hydroxyl and TMX-Urea by a series of reactions such as demethylation, oxadiazine ring cleavage and C=N substitution by hydroxy group. The main products were TMX-dm-hydroxyl and TMX-Urea, the amount of CLO production is relatively small. This study aims to provide a new approach for efficient degradation of TMX; furthermore, strain S1 is a promising biological source for in situ remediation of TMX contamination. [Display omitted] • Measured and analyzed the TMX concentration and its variation in the A2O process. • Isolation of Bacillus Cereus from the activated sludge of an A2O aerobic tank. • Bacillus cereus -S1 exhibits strong removal effect of TMX in wastewater. • A rational degradation pathway and three degradation products were proposed. [ABSTRACT FROM AUTHOR]

A method based on isotope dilution liquid chromatography/tandem mass spectrometry (ID-LC/MS/MS) was established as a candidate reference method for accurate determination of neonicotinoid pesticides, imidacloprid, clothianidin, and thiamethoxam in kimchi cabbage. Their deuterated isotopes, imidacloprid-d4, chlothianidin-d3, and thiamethoxam-d4 were used as internal standards. The combination of HLB and Carb solid-phase extraction (SPE) cartridges was used to clean-up kimchi cabbage extracts. The ID-LC/MS/MS conditions were optimized with fortified kimchi cabbage samples for validation. Imidacloprid in the ERM-BC403 cucumber sample (0.627 ± 0.026) mg/kg was analyzed with the developed method, and the measured value (0.604 ± 0.028) mg/kg agreed within their uncertainties. The developed method was employed for the certification of kimchi cabbage reference materials prepared in this laboratory. The measured values of imidacloprid, clothianidin, and thiamethoxam are (0.860 ± 0.020) mg/kg, (0.524 ± 0.012) mg/kg, (0.787 ± 0.014) mg/kg, respectively. The standard deviation of the measured values for ten bottles was < 1%, and the measured values after one year agreed with their first measurements indicating reliable repeatability and reproducibility of the developed method. [ABSTRACT FROM AUTHOR]

The European honey bee, Apis mellifera, is the most common and important pollinator of crops worldwide. Honey bees are damaged by destructive parasitic mites, but they also have evolved a behavioral immune system to remove them. Exposures to neonicotinoids, however, can cause significant behavioral effects because these compounds alter the central role of nicotinic acetylcholine receptor in insect brains. In this study, we assessed the effects of three neonicotinoids that have a high toxicity to bees—imidacloprid, thiamethoxam, and clothianidin—on the behavioral immune system of honey bees. We used A. mellifera and the endoparasitic mite Acarapis woodi as a behavioral immune system model because A. mellifera can effectively remove the mite by autogrooming. Our results did not demonstrate an effect of neonicotinoid application on whether bees show autogrooming or on mite removal, but the time to initial autogrooming became shorter and the number of autogrooming attempts increased. As opposed to previous studies, our findings indicate that the honey bee response to parasitic mites becomes more sensitive after exposure to neonicotinoids. Clinical Trials Registration: Not applicable [ABSTRACT FROM AUTHOR]

The present study evaluated the relative susceptibility of insecticides viz., imidacloprid, thiamethoxam, thiacloprid, flonicamid, clothianidin, diafenthiuron, spiromesifen, thiodicarb and chlorpyriphos against field collected population of Amrasca (S.) biguttula. Out of nine insecticides, maximum susceptibility was observed with thiamethoxam. The descending order of susceptibility was observed as thiamethoxam> thiacloprid> diafenthiuron> spiromesifen> imidacloprid> clothianidin> flonicamid> thiodicarb> chlorpyriphos. Based on the relative toxicity value it was observed that the insecticides such as chlorpyriphos, thiodicarb, flonicamid and clothianidin were 14.04, 12.01, 9.43 and 9.41x, respectively less toxic as compared to thiamethoxam. The detoxification enzyme assay revealed that the activity of esterase was high in thiamethoxam and thiacloprid exposed leafhopper, while cytochrome p450 activity was high in spiromesifen, thiamethoxam and thiacloprid exposed ones. Elevated level of esterase and cytochrome p450 in the insecticide exposed leafhoppers indicates the probability of insecticide resistance development. [ABSTRACT FROM AUTHOR]

Including probiotics in honeybee nutrition represents a promising solution for mitigating diseases, and recent evidence suggests that various microbes possess mechanisms that can bioremediate environmental pollutants. Thus, the use of probiotics capable of degrading pesticides used in modern agriculture would help to both reduce colony losses due to the exposure of foragers to these toxic molecules and improve honeybee health and wellbeing globally. We conducted in vitro experiments to isolate and identify probiotic candidates from bacterial isolates of the honeybee gut (i.e., endogenous strains) according to their ability to (i) grow in contact with three sublethal concentrations of the pesticide clothianidin (0.15, 1 and 10 ppb) and (ii) degrade clothianidin at 0.15 ppb. The isolated bacterial strains were indeed able to grow in contact with the three sublethal concentrations of clothianidin. Bacterial growth rate differed significantly depending on the probiotic candidate and the clothianidin concentration used. Clothianidin was degraded by seven endogenous honeybee gut bacteria, namely Edwardsiella sp., two Serratia sp., Rahnella sp., Pantoea sp., Hafnia sp. and Enterobacter sp., measured within 72 h under in vitro conditions. Our findings highlight that endogenous bacterial strains may constitute the base material from which to develop a promising probiotic strategy to mitigate the toxic effects of clothianidin exposure on honeybee colony health. [ABSTRACT FROM AUTHOR]

Background: Indoor residual spraying (IRS) is a major method of malaria vector control across sub-Saharan Africa. Effective control is being undermined by the rapid spread of insecticide resistance. There is major investment in development of new insecticides for IRS that possess novel modes of action, long residual activity, low mammalian toxicity and minimal cross-resistance. VECTRON™ T500, a new IRS product containing the active ingredient broflanilide as a 50% wettable powder (WP), has been shown to be efficacious against pyrethroid susceptible and resistant vector species on mud and concrete substrates in experimental hut (Phase II) trials.Methods: A two-arm non-inferiority cluster randomized controlled trial (Phase III) will be undertaken in Muheza District, Tanga Region, Tanzania. VECTRON™ T500 will be compared to the IRS product Fludora® Fusion (clothianidin 50% WP + deltamethrin 6.25% WP). The predominant malaria vectors in the study area are pyrethroid-resistant Anopheles gambiae s.s., An. arabiensis and An. funestus s.s. Sixteen village clusters will be pair-matched on baseline vector densities and allocated to reference and intervention arms. Consenting households in the intervention arm will be sprayed with VECTRON™ T500 and those in the reference arm will be sprayed with Fludora® Fusion. Each month, CDC light traps will collect mosquitoes to estimate changes in vector density, indoor biting, sporozoite and entomological inoculation rates (EIR). Susceptibility to IRS active ingredients will be assessed using World Health Organisation (WHO) bottle bioassays. Target site and metabolic resistance mechanisms will be characterised among Anopheles field populations from both trial arms. Residual efficacy of both IRS products will be monitored for 12 months post intervention. Questionnaire and focus group discussions will explore factors that influence adherence, adverse effects and benefits of IRS.Discussion: This protocol describes a large-scale non-inferiority evaluation of a novel IRS product to reduce the density and EIR of pyrethroid-resistant Anopheles vectors. If VECTRON™ T500 proves non-inferior to Fludora® Fusion, it will be considered as an additional vector control product for malaria prevention and insecticide resistance management.Trial Registration: ClinicalTrials.gov, NCT05150808, registered on 26 November 2021. Retrospectively registered. [ABSTRACT FROM AUTHOR]

Emergence and spread of malaria vectors resistant to the available insecticides required a new and efficacious insecticide. Residual efficacy of Fludora® Fusion was evaluated against insecticide susceptible Anopheles arabiensis in ten circular huts similar to the residential huts. Fludora® Fusion WP-SB 56.25, FICAM WP80 and Clothianidin WG70 were sprayed, by experienced technician, on interior wall surfaces: paint, dung, smooth mud, and rough mud. WHO cone bioassays were carried out a month after spraying and thereafter on monthly intervals for 12 months. Knockdown was recorded at 60 minutes and mortality at 24 hours, 48 hours and 72 hours holding time post-exposure. Fludora Fusion induced 100% An. arabiensis mortality during the first four months post-treated on all surface types at 24 hours holding time post-exposure. Its activity remained over 80% from the fifth to the twelfth month post-treated on the surfaces with the exception of two assessment points, at seventh month and eleventh month, on paint and smooth mud surfaces. FICAM induced 100% mortality rate during the first 4 months and 92% mortality during the fifth month post-treatment on painted surfaces. Its activity was over 96% mortality 1-month post-treatment on smooth mud and rough mud surfaces and 92% mortality 2-month post-treatment on dung surfaces. Clothianidin caused 89% and 86% mortality 1-month post-treatment on smooth mud and rough mud surfaces. Fludora Fusion can be used as alternative indoor residual insecticide spraying against An. arabiensis in Ethiopia. [ABSTRACT FROM AUTHOR]

A rapid and trace analytical method was established for the determination of thiamethoxam and its metabolite clothianidin in wheat leaves and wheat ears using ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Wheat leaves and wheat ears were extracted with acetonitrile and cleaned up with NH2 /Carb solid phase extraction column to remove impurities such as chlorophyll and starch. The internal standard method was used for quantitation. The results showed that the linearity of thiamethoxam and clothianidin was good in the range of 0.001- 0.5 mg/L, and the correlation coefficient was greater than 0.99. After internal standard correction, the recoveries of thiamethoxam and clothianidin in wheat leaves and wheat ears were in the range from 83.4% to 117.9% at 4 levels of 0.001, 0.01, 0.1 and 1 mg/kg, and the relative standard deviations were in the range of 1.6% to 13.0%. The limit of quantitation was 0.001 mg/kg. This method was used to determine the wheat leaves and wheat ears field samples after the wheat crops were sprayed with thiamethoxam 250 WG by unmanned aerial vehicle (UAV). The concentrations of thiamethoxam in wheat leaves and wheat ears were 4.24 and 1.34 mg/kg, respectively, at 2 h after application. On the 14th day after application, the concentrations of thiamethoxam and clothianidin were 0.097 and 0.079 mg/kg in wheat leaves, and were 0.031 and 0.046 mg/kg in wheat ears, respectively. This method can meet the detection requirements of wheat during the whole growth period, and it can also be used to study the conduction and distribution characteristics and residual metabolism of thiamethoxam and clothianidin in wheat plants. [ABSTRACT FROM AUTHOR]

BACKGROUND: Thiamethoxam is widely used to control pests in Chinese kale, popularly consumed leafy vegetables. The potential risk to the environment and human health has aroused much public concern. Therefore, it is important to investigate the degradation behavior, residue distribution and dietary risk assessment of thiamethoxam in Chinese kale. RESULTS: A sensitive analytical method for determination of thiamethoxam and its metabolite clothianidin residue in Chinese kale was established and validated through a quick, easy, cheap, effective, rugged, and safe (QuEChERS) technique with ultra‐performance liquid chromatography tandem mass spectrometry (UPLC–MS/MS). The recoveries were 85.4–101.2% for thiamethoxam and 79.5–108.1% for clothianidin, with the relative standard deviations (RSDs) of 0.9–10.2% and 1.8–6.0%, respectively. For the dissipation kinetics, the data showed that thiamethoxam in Chinese kale was degraded with the half‐lives of 4.1 to 4.5 days. In the terminal residue experiments, the residues of thiamethoxam were 0.017–0.357 mg kg−1 after application 2–3 times with a preharvest interval (PHI) of 7 days under the designed dosages. The chronic and acute dietary exposure assessment risk quotient (RQ) values of thiamethoxam in Chinese kale for different Chinese consumers were 0.08–0.19% and 0.05–0.12%, respectively, and those of clothianidin were 0.01–0.04% and 0.02–0.04%, respectively, all of the RQ values were lower than 100%. CONCLUSION: Thiamethoxam in Chinese kale was rapidly degraded following first‐order kinetics models. The dietary risk of thiamethoxam and clothianidin through Chinese kale was negligible to consumers. The results from this study are important reference for Chinese governments to developing criteria for the safe and rational use of thiamethoxam, setting maximum residue levels (MRLs), monitoring the quality safety of agricultural products and protecting consumer health. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Indoor residual spraying and insecticide-treated nets are among the key malaria control intervention tools. However, their efficacy is declining due to the development and spread of insecticide resistant vectors. In Ethiopia, several studies reported resistance of An. arabiensis to multiple insecticide classes. However, such data is scarce in irrigated areas of the country where insecticides, pesticides and herbicides are intensively used. Susceptibility of An. gambiae s.l. to existing and new insecticides and resistance mechanisms were assessed in Arjo-Didessa sugarcane plantation area, southwestern Ethiopia. Methods: Adult An. gambiae s.l. reared from larval/pupal collections of Arjo-Didessa sugarcane irrigation area and its surrounding were tested for their susceptibility to selected insecticides. Randomly selected An. gambiae s.l. (dead and survived) samples were identified to species using species-specific polymerase chain reaction (PCR) and were further analyzed for the presence of knockdown resistance (kdr) alleles using allele-specific PCR. Results: Among the 214 An. gambiae s.l. samples analyzed by PCR, 89% (n = 190) were An. amharicus and 9% (n = 20) were An. arabiensis. Mortality rates of the An. gambiae s.l. exposed to deltamethrin and alphacypermethrin were 85% and 86.8%, respectively. On the other hand, mortalities against pirmiphos-methyl, bendiocarb, propoxur and clothianidin were 100%, 99%, 100% and 100%, respectively. Of those sub-samples (An. amharicus and An. arabiensis) examined for presence of kdr gene, none of them were found to carry the L1014F (West African) allelic mutation. Conclusion: Anopheles amharicus and An. arabiensis from Arjo-Didessa sugarcane irrigation area were resistant to pyrethroids which might be synergized by extensive use of agricultural chemicals. Occurrence of pyrethroid resistant malaria vectors could challenge the ongoing malaria control and elimination program in the area unless resistance management strategies are implemented. Given the resistance of An. amharicus to pyrethroids, its behavior and vectorial capacity should be further investigated. [ABSTRACT FROM AUTHOR]

Within the EuroMix project, we have previously developed an adverse outcome pathway (AOP)-based in vitro assay toolbox to investigate the combined effects of liver steatosis-inducing compounds in human HepaRG hepatocarcinoma cells. In this study, we applied the toolbox to further investigate mixture effects of combinations, featuring either similarly acting or dissimilarly acting substances. The valproic acid structural analogs 2-propylheptanoic acid (PHP) and 2-propylhexanoic acid (PHX) were chosen for establishing mixtures of similarly acting substances, while a combination with the pesticidal active substance clothianidin (CTD) was chosen for establishing mixtures of dissimilarly acting compounds. We first determined relative potency factors (RPFs) for each compound based on triglyceride accumulation results. Thereafter, equipotent mixtures were tested for nuclear receptor activation in transfected HepG2 cells, while gene expression and triglyceride accumulation were investigated in HepaRG cells, following the proposed AOP for liver steatosis. Dose addition was observed for all combinations and endpoints tested, indicating the validity of the additivity assumption also in the case of the tested mixtures of dissimilarly acting substances. Gene expression results indicate that the existing steatosis AOP can still be refined with respect to the early key event (KE) of gene expression, in order to reflect the diversity of molecular mechanisms underlying the adverse outcome. [ABSTRACT FROM AUTHOR]

Few human data on exposure and toxicity are available on neonicotinoids and neonicotinoid-like compounds (NNIs), an important group of insecticides worldwide. Specifically, exposure assessment of humans by biomonitoring remains a challenge due to the lack of appropriate biomarkers. We investigated the human metabolism and metabolite excretion in urine of acetamiprid (ACE), clothianidin (CLO), flupyradifurone (FLUP), imidacloprid (IMI), sulfoxaflor (SULF), thiacloprid (THIAC) and thiamethoxam (THIAM) after single oral dosages at the currently acceptable daily intake levels of the European Food Safety Authority. Consecutive post-dose urine samples were collected up to 48 h. Suspect screening of tentative metabolites was carried out by liquid chromatography–high-resolution mass spectrometry. Screening hits were identified based on their accurate mass, isotope signal masses and ratios, product ion spectra, and excretion kinetics. We found, with the exception of SULF, extensive metabolization of NNIs to specific metabolites which were excreted next to the parent compounds. Overall, 24 metabolites were detected with signal intensities indicative of high metabolic relevance. Phase-I metabolites were predominantly derived by mono-oxidation (such as hydroxy-FLUP, -IMI, and -THIAC) and by oxidative N-desalkylation (such as N-desdifluoroethyl-FLUP and N-desmethyl-ACE, -CLO and -THIAM). IMI-olefin, obtained by dehydration of hydroxylated IMI, was identified as a major metabolite of IMI. SULF was excreted unchanged in urine. Previously reported metabolites of NNIs such as 6-chloronicotinic acid or 2-chlorothiazole-4-carboxylic acid and their glycine derivatives were detected either at low signal intensities or not at all and seem less relevant for human biomonitoring. Our highly controlled approach provides specific insight into the human metabolism of NNIs and suggests suitable biomarkers for future exposure assessment at environmentally relevant exposures. [ABSTRACT FROM AUTHOR]

A field experiment was conducted to evaluate the bio-efficacy and phytotoxicity of Thiocyclam hydrogen oxalate 3% + Clothianidin 1.2% GR against major paddy pests during Kharif, 2020 and Rabi, 2021. The treatments were: T1 - Thiocyclam hydrogen oxalate 3% + Clothianidin 1.2% GR @ 225+90 g a.i./ha; T2 - Thiocyclam hydrogen oxalate 3% + Clothianidin 1.2% GR @ 300+120 g a.i./ha; T3 - Thiocyclam hydrogen oxalate 3% + Clothianidin 1.2% GR @ 375+150 g a.i./ ha; T4 - Thiocyclam hydrogen oxalate 4% GR @ 500 g a.i./ha; T5 - Clothianidin 50% WDG @ 12 g a.i./ha and T6 - Clothianidin 50% WDG @ 125 g a.i./ha, T7 - Cartap hydrochloride 4% GR @ 1000 g a.i./ha and T8 -Untreated check. Results revealed that, all the treatments were effective in controlling stem borer damage, leaf folder damage, Brown planthopper and White backed plant hopper population and significant increase in yield but among the tested chemicals Thiocyclam hydrogen oxalate 3% + Clothianidin 1.2% GR @ 375+150 and 300+120 g a.i./ha showed highest control of pests at 20 days after treatment. The test compound was found to be relatively safe to natural enemies in the paddy ecosystem and also did not cause any kind of phytotoxicity [ABSTRACT FROM AUTHOR]

Neonicotinoid insecticides have been implicated in honey bee declines, with many studies showing that sublethal exposure impacts bee behaviors such as foraging, learning, and memory. Despite the large number of ecotoxicological studies carried out to date, most focus on a handful of worker phenotypes leading to a "streetlight effect" where the a priori choice of phenotypes to measure may influence the results and conclusions arising from the studies. This bias can be overcome with the use of toxicological transcriptomics, where changes in gene expression can provide a more objective view of how pesticides alter animal traits. Here, we used RNA sequencing to examine the changes in neurogenomic states of nurse and forager honey bees that were naturally exposed to neonicotinoids in the field and artificially exposed to neonicotinoids in a controlled experiment. We found that neonicotinoid exposure influenced the neurogenomic state of foragers and nurses in different ways; foragers experienced shifts in expression of genes involved in cognition and development, while nurses experienced shifts in expression of genes involved in metabolism. Our study suggests that neonicotinoids influence nurse and forager bees in a different manner. We also found no to minimal overlap in the differentially expressed genes in our study and in previously published studies, which might help reconcile the seemingly contradictory results often reported in the neonicotinoid literature. [ABSTRACT FROM AUTHOR]

Insecticides are the most economic and quick tool to control harmful agricultural insect pests which reduce crop productivity. However, these insecticides have a suppressive and negative impact on non-targeted beneficial fauna. The efficiency and mode of action of numerous insecticides are also much diverse. Therefore, we studied the sublethal impact of bifenthrin (pyrethroids) and clothianidin (neonicotinoids) on ladybird beetle Coccinella septempunctata L. (Coleoptera: Coccinellidae), taking these insecticides as the model representative for the insecticide groups. Our results revealed that both insecticides enhanced the life length of male and female adults of ladybird beetle as compared to control treatment. Bifenthrin reduced the survival rate of larvae and adults as compared to clothianidin and control as well as lowered the fecundity rate of C. septempunctata. After control treatment, the developmental period of each larval instar was shorter in clothianidin than bifenthrin. Adult emergence was also less in clothianidin than in the control group. However, clothianidin triggered the fecundity of the female ladybird beetle. Higher fecundity was recorded in clothianidin treatment as compared to bifenthrin and control which means clothianidin is a better option in integrated pest management (IPM) program as compared to bifenthrin involving the ladybird beetle as a natural biocontrol agent. [ABSTRACT FROM AUTHOR]

Contemporary non-target effects of conventional synthetic insecticides necessitate evaluating biorational insecticides owing differential chemistry and modes of action than the conventional ones. This laboratory study comparatively evaluated some selected differential chemistry insecticides against some destructive and economically important insect pests i.e. mango mealybug (Drosicha mangiferae Green), mango leafhopper (Idioscopus clypealis Lethierry), Asian citrus psyllid (Diaphorina citri Kuwayama) and subterranean termites (Odontotermes obesus Rambur). Standard twig- and filter paper-dip bioassay methods were used against sap-feeding pests and termites, respectively. Factorial analyses of variance revealed a significant impact of tested insecticidal formulations and exposure time on the mortality all insect pest individuals. The most effective differential chemistry insecticides against mango leafhopper, citrus psyllids, mango mealybugs and subterranean termites were nitenpyram, clothianidin, thiamethoxam and imidacloprid (causing 74-79% cumulative corrected mortality), thiamethoxam, imidacloprid, clothianidin and spirotetramat (causing 78-85% cumulative mortality), spirotetramat, acetamiprid and thiamethoxam (causing 68-90% cumulative mortality), and chlorantraniliprole, pyriproxyfen and chlorfenapyr (causing 80-85% cumulative mortality), respectively. Overall study findings suggest these above mentioned non-conventional insecticides to be incorporated in the biorational management of these insect pests. [ABSTRACT FROM AUTHOR]

Copyright of Avian Conservation & Ecology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Neonicotinoids are pesticides that act as agonists of nicotinic receptors for acetylcholine in insects' central nervous system (CNS). Chronic exposure to neonicotinoids in humans is related to autism, memory loss, and finger tremor. In this article, we evaluate the effect of subchronic oral administration of two neonicotinoids in the same mixture: clothianidin and thiacloprid. Decreasing doses of both pesticides were administered to rats starting from the lethal dose 50 (LD50) reported by the manufacturer. Our results indicate that the administration of three doses of decreasing amounts of LD50 (5/10, 4/10, and 3/10 LD50) resulted in 100% death in all cases. Ten administration times of 2/10 LD50 of the mixture caused only 20% of death cases after twenty-seven days, which was determined as a subchronic administration scheme. The animals administered 2/10 LD50 showed behavioral alterations after the first and second administration. Electrographic studies showed abnormal discharge patterns in the CNS. 72 h after the tenth dose, learning and memory tests were performed in the Morris water maze. Our results revealed significant decreases in permanence at the quadrant and the number of crosses (P = 0.0447 , P = 0.0193 , respectively), which represent alterations in the short-term memory test, but there were no significant changes in a long-term memory test. Likewise, the brains of these animals showed tissue architecture loss, nucleosomal retraction, and a significant increase in the pycnosis of the granular neurons of the dentate gyrus analyzed at 72 h after the last dose (P = 0.0125). Toxic effects and cognitive deterioration that have been found in communities living near contaminated areas are probably related to the agricultural use of neonicotinoids. [ABSTRACT FROM AUTHOR]

Polar organic chemical integrative sampler (POCIS) devices have been suggested for measuring time‐weighted averages (TWAs) of contaminant concentrations resulting from chemical leak accidents in aquatic environments. However, the response of the POCIS device in the emergency condition in natural water remains unclear. The response of the POCIS device to contaminant fluctuation was investigated using a chamber test with tap water and a channel test with natural water. The fluctuation in the chamber and the channel simulated the condition of river water under a chemical leak scenario (maximum concentration: 1–10 μg L–1, half‐life: 1 day). The target chemicals were neonicotinoid pesticides (dinotefuran, clothianidin, thiamethoxam, imidacloprid, acetamiprid, and thiacloprid) and bisphenol A. The ratio of the POCIS measured value to the TWA values of grab samplings (POCIS/TWA) for the channel test (temperature: 15 °C, flow velocity: 15 cm s–1) ranged from 61% (clothianidin) to 133% (thiacloprid). The results indicated that the POCIS device could be effectively used as a monitoring device in an aquatic environment under the chemical leak scenario over a time period of more than14 days. In addition, the POCIS/TWA ratios obtained from the chamber test and the channel test were in the range of 50–150%. Thus, the chamber test could be used to evaluate the POCIS device at a low cost. Environ Toxicol Chem 2021;40:3010–3018. © 2021 SETAC [ABSTRACT FROM AUTHOR]

The European Food Safety Authority (EFSA) was requested by the European Commission to provide technical assistance in accordance with Article 53(2) of Regulation (EC) No 1107/2009 to examine the emergency authorisations granted in 2019 and 2020 by the competent national authority in Belgium for plant protection products containing the neonicotinoid active substances (a.s.) clothianidin, imidacloprid, or thiamethoxam for uses on sugar beet which were restricted when all outdoor uses were prohibited in May 2018. EFSA was asked to assess whether the granting of these emergency authorisations and their wide scope were necessary because of danger which cannot be contained by any other reasonable means. In this context, EFSA collected and evaluated the information in relation to the emergency authorisations for clothianidin, imidacloprid and thiamethoxam in Belgium in line with the EFSA insecticide protocol developed in the framework of a mandate concerning the application of Article 4(7) of Regulation (EC) No 1107/2009. This technical report summarises the evaluation of eight crop/pest combinations considered in Belgium in 2019 and 2020. An evaluation in line with this protocol is not relevant for emergency authorisations granted for plant protection products for export to countries where the sowing of the seeds is allowed. The evaluation demonstrated that for all eight crop/pest combinations (sugar beet/aphids, millipedes, centipedes, flea beetle, wireworms, pygmy mangold beetle, leatherjackets and beet fly) no sufficient alternative a.s. to clothianidin and thiamethoxam are currently authorised in Belgium in order to provide an alternative mode of action (MoA). The evaluation included an assessment of non‐insecticide alternatives for the presented uses. For the sugar beet, fodder beet/wireworms and sugar beet, fodder beet/leatherjackets combinations one non‐insecticide method (crop rotation) is considered as highly effective and feasible and is used on a large scale. This publication is linked to the following EFSA Supporting Publications articles: http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6958/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6959/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6960/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6962/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6963/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6964/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6965/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6966/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6967/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6968/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6969/full [ABSTRACT FROM AUTHOR]

The European Food Safety Authority (EFSA) was requested by the European Commission to provide technical assistance in accordance with Article 53(2) of Regulation (EC) No 1107/2009 to examine the emergency authorisations granted in 2020 by the competent national authority in Spain for plant protection products containing the neonicotinoid active substances (a.s.) clothianidin, imidacloprid or thiamethoxam for uses on sugar beet which were restricted when all outdoor uses were prohibited in May 2018. EFSA was asked to assess whether the granting of this emergency authorisation and its wide scope was necessary because of danger which cannot be contained by any other reasonable means. In this context, EFSA collected and evaluated the information in relation to the emergency authorisation for clothianidin in Spain in line with the EFSA insecticide protocol developed in the framework of a mandate concerning the application of Article 4(7) of Regulation (EC) No 1107/2009. The current Technical Report summarises the outcome of the evaluation of four crop/pest combinations considered in Spain in 2020. The evaluation demonstrated that for every crop/pest combination no sufficient alternative active substance to clothianidin is currently authorised in Spain, in order to provide an alternative mode of action (MoA). The evaluation included an assessment of non‐insecticide alternatives for the presented uses. Early planting is a common measure for all pests. Other available measures include frequent soil tillage and conservation biocontrol of soil predators (for wireworms and Onychiurus armatus), rotation and avoidance of soil tillage (for Chaetocnema tibialis), control of host weeds (for Chaetocnema tibialis and aphids), and conservation and inoculative biocontrol (for aphids). However, all these measures are considered as moderately effective, they are feasible with restrictions and they are used in a small scale (i.e. applied on up to 10% of the acreage of the crop). This publication is linked to the following EFSA Supporting Publications articles: http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6958/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6959/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6961/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6962/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6963/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6964/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6965/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6966/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6967/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6968/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6969/full [ABSTRACT FROM AUTHOR]

The European Food Safety Authority (EFSA) was requested by the European Commission to provide technical assistance in accordance with Article 53(2) of Regulation (EC) No 1107/2009 to examine the emergency authorisations granted in 2020 by the competent national authority in Finland for plant protection products containing the neonicotinoid active substances (a.s.) clothianidin, imidacloprid or thiamethoxam for uses on sugar beet which were restricted when all outdoor uses were prohibited in May 2018. EFSA was asked to assess whether the granting of this emergency authorisation and its wide scope was necessary because of danger which cannot be contained by any other reasonable means. In this context, EFSA collected and evaluated the information in relation to the emergency authorisation for clothianidin, imidacloprid and thiamethoxam in Finland in line with the EFSA insecticide protocol developed in the framework of a mandate concerning the application of Article 4(7) of Regulation (EC) No 1107/2009. The current technical report summarises the outcome of the evaluation of four crop/pest combinations considered in Finland in 2020. The evaluation demonstrated that for the examined pests (Phyllotreta sp., Lygus sp., Pegomya hyoscyani, Pegomyia betae, Agriotes lineatus, Atomaria linearis, Blaniulus sp. and Scutigerella immaculata) no other insecticides or not sufficient alternative active substances to neonicotinoids are currently authorised in Finland in order to provide alternative mode of actions (MoA). Possible non‐insecticide alternative methods listed to control sugar beet insects in Finland are: crop rotation (applied in more than 50% of the acreage of the crop) and preservation of soil quality that are moderately effective. This publication is linked to the following EFSA Supporting Publications articles: http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6958/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6960/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6961/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6962/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6963/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6964/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6965/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6966/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6967/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6968/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2021.EN-6969/full [ABSTRACT FROM AUTHOR]

Background. Previous research suggests that fireflies (Coleoptera: Lampyridae) are susceptible to commonly used insecticides. In the United States, there has been a rapid and widespread adoption of neonicotinoid insecticides, predominantly used as seed coatings on large-acreage crops like corn, soy, and cotton. Neonicotinoid insecticides are persistent in soil yet mobile in water, so they have potential to contaminate firefly habitats both in and adjacent to application sites. As a result, fireflies may be at high risk of exposure to neonicotinoids, possibly jeopardizing this already at-risk group of charismatic insects. Methods. To assess the sensitivity of fireflies to neonicotinoids, we exposed larvae of Photuris versicolor complex and Photinus pyralis to multiple levels of clothianidin- treated soil and monitored feeding behavior, protective soil chamber formation, intoxication, and mortality. Results. Pt. versicolor and Pn. pyralis larvae exhibited long-term intoxication and mortality at concentrations above 1,000 ng g-1 soil (1 ppm). Under sub-lethal clothianidin exposure, firefly larvae fed less and spent less time in protective soil chambers, two behavioral changes that could decrease larval survival in the wild. Discussion. Both firefly species demonstrated sub-lethal responses in the lab to clothianidin exposure at field-realistic concentrations, although Pt. versicolor and Pn. pyralis appeared to tolerate higher clothianidin exposure relative to other soil invertebrates and beetle species. While these two firefly species, which are relatively widespread in North America, appear somewhat tolerant of neonicotinoid exposure in a laboratory setting, further work is needed to extend this conclusion to wild populations, especially in rare or declining taxa. [ABSTRACT FROM AUTHOR]

BACKGROUND Neonicotinoids comprise one of the most extensively used classes of pesticides worldwide owing to their broad insecticidal spectrum and excellent biological performance. However, their toxicity to honeybee (Apis mellifera Linnaeus) and silkworm (Bombyx Mori) limits their further application. To address this issue, clothianidin as a model neonicotinoid was developed into a novel controlled‐release formulation employing advantaged solid dispersion (SD) technology using composite carriers. RESULTS: In this research, the clothianidin‐loaded SD was characterized using integrated methods to elucidate its formation mechanism, showing that clothianidin was embedded into the carrier homogeneously in small crystalline entities. The composite carriers, which are both renewable and environmentally friendly, can significantly prolong the release of clothianidin from seven to 25 days, compared with that of PEG 8000 as a single carrier. Based on the excellent controlled release profiles, it reduced the acute toxicity to A. mellifera and B. mori by 57.68‐ and 85.32‐fold (respectively) compared with that of the conventional formulation. Furthermore, the SD displayed favorable efficacy and persistency against Asian citrus psyllid (Hemiptera: Psyllidae). CONCLUSION: This novel strategy opens up a simple and powerful avenue for improving efficacy and promoting the environmental safety of neonicotinoid insecticides to be used in sustainable crop protection. [ABSTRACT FROM AUTHOR]

Western honey bees (Apis mellifera) are ecologically, agriculturally, and economically important plant pollinators. High average annual losses of honey bee colonies in the US have been partially attributed to agrochemical exposure and virus infections. To examine the potential negative synergistic impacts of agrochemical exposure and virus infection, as well as the potential promise of phytochemicals to ameliorate the impact of pathogenic infections on honey bees, we infected bees with a panel of viruses (i.e., Flock House virus, deformed wing virus, or Sindbis virus) and exposed to one of three chemical compounds. Specifically, honey bees were fed sucrose syrup containing: (1) thyme oil, a phytochemical and putative immune stimulant, (2) fumagillin, a beekeeper applied fungicide, or (3) clothianidin, a grower-applied insecticide. We determined that virus abundance was lower in honey bees fed 0.16 ppm thyme oil augmented sucrose syrup, compared to bees fed sucrose syrup alone. Parallel analysis of honey bee gene expression revealed that honey bees fed thyme oil augmented sucrose syrup had higher expression of key RNAi genes (argonaute-2 and dicer-like), antimicrobial peptide expressing genes (abaecin and hymenoptaecin) , and vitellogenin , a putative honey bee health and age indicator, compared to bees fed only sucrose syrup. Virus abundance was higher in bees fed fumagillin (25 ppm or 75 ppm) or 1 ppb clothianidin containing sucrose syrup relative to levels in bees fed only sucrose syrup. Whereas, honey bees fed 10 ppb clothianidin had lower virus levels, likely because consuming a near lethal dose of insecticide made them poor hosts for virus infection. The negative impact of fumagillin and clothianidin on honey bee health was indicated by the lower expression of argonaute-2 , dicer-like , abaecin , and hymenoptaecin , and vitellogenin. Together, these results indicate that chemical stimulants and stressors impact the outcome of virus infection and immune gene expression in honey bees. [ABSTRACT FROM AUTHOR]

In order to provide theoretical basis for guiding scientific use of 18% clothianidin embedding GR and reducing environmental risk, the correlation between the accumulative amount and the control efficacy on whitefly of 18% clothianidin embedding GR and the dynamics of residual dissipation were investigated on greenhouse cucumbers. Under greenhouse conditions, using 1% clothianidin GR as the control agent, the control efficacy of 18% clothianidin embedding GR on whitefly was investigated. An ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was established for the determination of clothianidin residues in cucumber leaves and soil. The accumulative amount of clothianidin in cucumber leaves at different application dosages and different growth stages was determined, and the correlation between the accumulative amount and control efficacy was studied. The results showed that the control efficacy of 18% clothianidin embedding GR on whitefly was 49%- 95%, which was 1.16-2.32 times higher than that of 1% clothianidin GR, and the ideal control efficacy of 18% clothianidin GR granules could be achieved at 450 g a.i./hm² . The residue dissipation dynamic of clothianidin in soil was in accordance with the first-order kinetic equation. The half-life of 18% clothianidin embedding GR was 43-63 days, while that of 1% clothianidin GR was 35 days, which showed that 18% clothianidin embedding GR had a slow dissipation rate in soil. The accumulative amount of clothianidin in cucumber leaves increased with the increase of the dosage of 18% clothianidin embedding GR. Both the cumulative amount and the control efficacy on whitefly showed a trend of first increasing and then decreasing with the passage of the time after application, and reached the highest value on 56th days after application. When the application rates of active ingredients were 450, 600 and 750 g/hm², the maximum accumulation of clothianidin in upper leaves of cucumber were 1.9, 2.2 and 2.8 mg/kg, respectively, and the highest control efficacy were all 90%. The maximum accumulation of clothianidin in middle leaves were 2.2, 2.5 and 3.0 mg/kg, and the highest control efficacy were 94%, 93% and 95%, respectively. [ABSTRACT FROM AUTHOR]

Bumblebees can be exposed to neonicotinoid pesticides through nectar and pollen collected from treated crops, which can cause lethal and sublethal effects in these nontarget pollinators. However, the body distribution of the compound after exposure to neonicotinoids in bumblebees is not well studied. Bumblebee colonies (Bombus terrestris, n = 20) were exposed to field‐realistic concentrations of clothianidin through artificial nectar (3.6–13 µg/L) for 9 d. Comparison of the nominal with the measured exposure in nectar indicated good compliance, confirming the applicability of the method. When quantified, clothianidin showed a concentration‐dependent occurrence in the head and body of workers (head: <0.2–2.17 µg/kg; body: <0.2–3.17 µg/kg), and in the body of queens (<0.2–2.49 µg/kg), although concentrations were below those measured in the nectar (bioaccumulation factor = 0.2). Exposure to clothianidin did not affect mortality nor brood production, nor did it have a statistically significant effect on nectar consumption and size of food storage. However, visual inspection suggests higher nectar consumption of nectar with low clothianidin content compared with nectar with no or high clothianidin content. Our results show that dietary clothianidin is taken up in bumblebees, but does not bioaccumulate to elevated levels compared with exposure. Still, clothianidin may elicit responses that affect feeding behavior of the pollinator B. terrestris, although our endpoints were not significantly affected. Environ Toxicol Chem 2021;40:2781–2790. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

BACKGROUND: Nilaparvata lugens, a destructive rice pest in Asia, has developed resistance to many insecticides, including the neonicotinoid clothianidin. CYP6ER1 plays an important role in N. lugens resistant to clothianidin, but only limited information on the transcriptional regulation of CYP6ER1 overexpression in clothianidin resistance is available. RESULTS: In this study, the transcription factor activator protein 1 (AP‐1) was found to be overexpressed in a clothianidin‐resistant strain of N. lugens and several field resistant populations. RNA interference‐mediated silencing of NlAP‐1 significantly decreased CYP6ER1 expression and increased the susceptibility of N. lugens to clothianidin. Additionally, NlAP‐1 was highly expressed in egg and adult stages, and in midguts, and NlAP‐1 was upregulated and induced to a greater extent in the clothianidin‐resistant strain after exposure to clothianidin. Finally, dual‐luciferase reporter assays confirmed the interaction between NlAP‐1 and the two predicted binding sites in the CYP6ER1 promoter. CONCLUSION: NlAP‐1 bound the −1388 to −1208‐bp region of the CYP6ER1 promoter, enhancing its activity and then regulate the expression of CYP6ER1. These findings enhance our knowledge of the transcriptional regulation of the P450 genes that mediate insecticide resistance in insect pests. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Taiwan Agricultural Research is the property of Taiwan Agricultural Research Institute, Council of Agriculture, Executive Yuan and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Background A new generation of IRS insecticides which can provide improved and prolonged control of pyrethroid-resistant malaria vector populations are being developed. Fludora® Fusion is a new IRS insecticide containing a mixture of deltamethrin and clothianidin, a neonicotinoid. Methods The efficacy of Fludora® Fusion IRS was evaluated over 11–12 months on concrete and mud substrates in laboratory bioassays and experimental huts against wild free-flying pyrethroid-resistant Anopheles gambiae (sensu lato) in Cové, Benin. A comparison was made with the two active ingredients of the mixture; clothianidin and deltamethrin, applied alone. CDC bottle bioassays were also performed to investigate resistance to clothianidin in the wild vector population. Results Fludora® Fusion induced > 80% laboratory cone bioassay mortality with both susceptible and pyrethroid-resistant An. gambiae (s.l.) for 7–9 months on concrete block substrates and 12 months on mud block substrates. The vector population at the experimental hut site was fully susceptible to clothianidin in CDC bottle bioassays. Overall mortality rates of wild free-flying pyrethroid-resistant An. gambiae (s.l.) entering the experimental huts during the 11-month trial were 80%) only declined by 50% after 8 months. Monthly in situ wall cone bioassay mortality of susceptible mosquitoes was > 80% for 9–12 months with Fludora® Fusion and clothianidin alone. Fludora® Fusion induced significantly higher levels of early exiting of mosquitoes compared to clothianidin alone (55–60% vs 37–38%, P

Between 2013 and 2018, there was an outbreak of sudden foraging honey bee deaths in Turkey’s Çukurova Region from the beginning of February to the middle of March, a period of time when the sowing of maize seeds occurs in the region. Upon returning, the affected bees were unable to enter the hive because of unbalanced flying and walking. Deaths were seen at apiaries located on plains or near plains where maize seeds were sowed. When winds blew from the direction of the plains towards the hives, honey bee deaths increased, but when the weather was rainy, honey bee deaths decreased or stopped. Honey bee losses were mainly between 30% and 80%. Investigations related to the honey bee deaths were carried out in the affected apiaries using on-site inspection and laboratory tests. The main reason of deaths would be linked to the clothianidin coated maize seeds used in the plain during sowing period. No remarkable correlation with any bee pathogens was detected related to the sudden and prevalent honey bee deaths.

Background Previous research suggests that fireflies (Coleoptera: Lampyridae) are susceptible to commonly used insecticides. In the United States, there has been a rapid and widespread adoption of neonicotinoid insecticides, predominantly used as seed coatings on large-acreage crops like corn, soy, and cotton. Neonicotinoid insecticides are persistent in soil yet mobile in water, so they have potential to contaminate firefly habitats both in and adjacent to application sites. As a result, fireflies may be at high risk of exposure to neonicotinoids, possibly jeopardizing this already at-risk group of charismatic insects. Methods To assess the sensitivity of fireflies to neonicotinoids, we exposed larvae of Photuris versicolor complex and Photinus pyralis to multiple levels of clothianidin-treated soil and monitored feeding behavior, protective soil chamber formation, intoxication, and mortality. Results Pt. versicolor and Pn. pyralis larvae exhibited long-term intoxication and mortality at concentrations above 1,000 ng g−1 soil (1 ppm). Under sub-lethal clothianidin exposure, firefly larvae fed less and spent less time in protective soil chambers, two behavioral changes that could decrease larval survival in the wild. Discussion Both firefly species demonstrated sub-lethal responses in the lab to clothianidin exposure at field-realistic concentrations, although Pt. versicolor and Pn. pyralis appeared to tolerate higher clothianidin exposure relative to other soil invertebrates and beetle species. While these two firefly species, which are relatively widespread in North America, appear somewhat tolerant of neonicotinoid exposure in a laboratory setting, further work is needed to extend this conclusion to wild populations, especially in rare or declining taxa.

Beekeepers need new treatment options for controlling small hive beetles ( Aethina tumida ), a devastating honey bee ( Apis mellifera ) pest. For many years, commercial beekeepers in the U.S. have used gel roach baits off-label as a method for treating SHBs. Herein, we evaluated the acute toxicity of active ingredients commonly found in gel roach baits, including abamectin, clothianidin, hydramethylnon, fipronil, and indoxacarb through topical and oral routes of exposure against SHBs and honey bees. Additionally, coumaphos, the active ingredient of the only registered in-hive control treatment for SHBs, was evaluated to provide a comparison to the gel roach bait active ingredients. Fipronil was the most toxic compound to SHBs topically (LD 50 = 0.23 ng/SHB) and through pollen (LC 50 = 0.06 µg/g pollen). Fipronil (LD 50 = 0.31 ng/honey bee) had a selectivity ratio of 1.3, suggesting that it is more toxic to SHBs than it is to honey bees, but only to a small degree. Abamectin, clothianidin, hydramethylnon, and indoxacarb had a higher toxicity to honey bees than to SHBs through topical exposure. Our results suggest that gel roach baits and their active ingredients are toxic to honey bees and pose a serious risk to colony safety if used as in-hive treatments.

Background: Anopheles mosquito resistance to insecticide remains a serious threat to malaria vector control affecting several sub-Sahara African countries, including Côte d'Ivoire, where high pyrethroid, carbamate and organophosphate resistance have been reported. Since 2017, new insecticides, namely neonicotinoids (e.g.; clothianidin) and pyrroles (e.g.; chlorfenapyr) have been pre-qualified by the World Health Organization (WHO) for use in public health to manage insecticide resistance for disease vector control., Methods: Clothianidin and chlorfenapyr were tested against the field-collected Anopheles gambiae populations from Gagnoa, Daloa and Abengourou using the WHO standard insecticide susceptibility biossays. Anopheles gambiae larvae were collected from several larval habitats, pooled and reared to adulthood in each site in July 2020. Non-blood-fed adult female mosquitoes aged 2 to 5 days were exposed to diagnostic concentration deltamethrin, permethrin, alpha-cypermethrin, bendiocarb, and pirimiphos-methyl. Clothianidin 2% treated papers were locally made and tested using WHO tube bioassay while chlorfenapyr (100 µg/bottle) was evaluated using WHO bottle assays. Furthermore, subsamples of exposed mosquitoes were identified to species and genotyped for insecticide resistance markers including the knock-down resistance (kdr) west and east, and acetylcholinesterase (Ace-1) using molecular techniques., Results: High pyrethroid resistance was recorded with diagnostic dose in Abengourou (1.1 to 3.4% mortality), in Daloa (15.5 to 33.8%) and in Gagnoa (10.3 to 41.6%). With bendiocarb, mortality rates ranged from 49.5 to 62.3%. Complete mortality (100% mortality) was recorded with clothianidin in Gagnoa, 94.9% in Daloa and 96.6% in Abengourou, while susceptibility (mortality > 98%) to chlorfenapyr 100 µg/bottle was recorded at all sites and to pirimiphos-methyl in Gagnoa and Abengourou. Kdr-west mutation was present at high frequency (0.58 to 0.73) in the three sites and Kdr-east mutation frequency was recorded at a very low frequency of 0.02 in both Abengourou and Daloa samples and absent in Gagnoa. The Ace-1 mutation was present at frequencies between 0.19 and 0.29 in these areas. Anopheles coluzzii represented 100% of mosquitoes collected in Daloa and Gagnoa, and 72% in Abengourou., Conclusions: This study showed that clothianidin and chlorfenapyr insecticides induce high mortality in the natural and pyrethroid-resistant An. gambiae populations in Côte d'Ivoire. These results could support a resistance management plan by proposing an insecticide rotation strategy for vector control interventions., (© 2024. The Author(s).)

For malaria control, the application of long-lasting insecticidal nets and indoor residual spraying has led to a significant reduction in morbidity and mortality. However, the sustainability of these gains is hampered by the increase in insecticide resistance. It is therefore judicious to evaluate new insecticide formulations. In comparison to clothianidin and deltamethrin, the efficacy and residual effect of Fludora® Fusion was evaluated using an Anopheles coluzzii laboratory and An. arabiensis wild colonies in huts from August 2016 to June 2017 on cement and mud walls. Mortality was recorded at 24, 48, 72, and 96 h post exposure. Like deltamethrin and clothianidin, Fludora® Fusion showed delayed mortality rates above the WHO’s 80% threshold over a period of 11 months with the laboratory strain. With the wild strain, while residual efficacy was observed at 2 months for the three insecticides, no residual efficacy was observed at 8 months at 24 h in both substrates. However, the increased efficacy was observed with increased holding periods (72 h and 96 h). These findings suggest that Fludora® Fusion could be an alternative candidate since this duration covers the transmission period in most areas in Senegal.

Background: Insecticide resistance—and especially pyrethroid resistance—is a major challenge for vector control in public health. The use of insecticide mixtures utilizing alternative modes of action, as well as new formulations facilitating their uptake, is likely to break resistance and slow the development of resistance. Methods: We used genetically defined highly resistant lines of Drosophila melanogaster with distinct target-site mutations and detoxification enzymes to test the efficacy and anti-resistance potential of novel mixture formulations (i.e. Fludora® Fusion consisting of deltamethrin and clothianidin), as well as emulsifiable concentrate transfluthrin, compared to alternative, currently used pyrethroid insecticide formulations for vector control. Results: The commercial mixture Fludora® Fusion, consisting of both a pyrethroid (deltamethrin) and a neonicotinoid (clothianidin), performed better than either of the single active ingredients against resistant transgenic flies. Transfluthrin, a highly volatile active ingredient with a different molecular structure and primary exposure route (respiration), was also efficient and less affected by the combination of metabolic and target-site resistance. Both formulations substantially reduced insecticide resistance across different pyrethroid-resistant Drosophila transgenic strains. Conclusions: The use of mixtures containing two unrelated modes of action as well as a formulation based on transfluthrin showed increased efficacy and resistance-breaking potential against genetically defined highly resistant Drosophila flies. The experimental model remains to be validated with mosquito populations in the field. The possible introduction of new transfluthrin-based products and mixtures for indoor residual spraying, in line with other combination and mixture vector control products recently evaluated for use in public health, will provide solutions for better insecticide resistance management. [ABSTRACT FROM AUTHOR]

BACKGROUND Uridine diphosphate‐glycosyltransferases (UGTs) are phase II metabolic enzymes involved in metabolism of toxins and resistance to insecticides in insect pests. Reactive oxygen species (ROS) induced by xenobiotics are important for activation of detoxification pathways. However, relationships between ROS and UGTs involved in toxin metabolism and insecticide resistance remain unclear. RESULTS: Here, involvement of dual oxidase (Duox)‐dependent ROS in regulating UGT expression‐mediated insecticide resistance in the brown planthopper (Nilaparvata lugens) was investigated. The overexpression of NlUGT386F2 contributed to the resistance of N. lugens to clothianidin. Furthermore, the ROS inhibitor (N‐acetylcysteine) significantly reduced the expression of NlUGT386F2 and increased the susceptibility of N. lugens to clothianidin. Silencing the ROS producer Duox significantly increased the susceptibility of N. lugens to clothianidin through the down‐regulation of NlUGT386F2 expression. CONCLUSION: NlDuox‐dependent ROS regulates NlUGT386F2 expression‐mediated clothianidin resistance in brown planthopper. These observations further our understanding of the metabolism of toxins and of insecticide‐resistance in insect pests. [ABSTRACT FROM AUTHOR]

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Neonicotinoid insecticides (NNIs) are now popular in many agricultural systems across Africa; however, the extent of human exposures to NNIs in African countries is scarcely reported. The present study evaluates neonicotinoid exposures in the consumer population of Kumasi, a cosmopolitan city in Ghana. A total of 75 human urine samples were collected from healthy volunteers (nonfarmers, aged 13–80 yr) and analyzed with a liquid chromatography electrospray ionization tandem mass spectrometry system. Seven NNIs and 3 NNI metabolites were detected in the following pattern (frequency, median concentration, maximum concentration): N‐dm‐acetamiprid (94.7%, 0.41 µg/L, 8.79 µg/L) > imidacloprid (70.7%, 0.15 µg/L, 211.62 µg/L) > N‐(6‐chloro‐3‐pyridylmethyl)‐N‐ethyl‐N′‐methylformamidine (62.2%, 0.43 µg/L, 53.85 µg/L) > 2‐[N‐(6‐chloro‐3‐pyridylmethyl)‐N‐ethylamino]‐2‐(methylimino)acetic acid (56.8%, 0.10 µg/L, 3.53 µg/L) > clothianidin (40%, >limit of quantification [LOQ], 0.45 µg/L) > nitenpyram (18.7%, >LOQ, 0.14 µg/L) ≈ thiamethoxam (18.7%, >LOQ, 0.21 µg/L) > dinotefuran (12.0%, >LOQ, 1.01 µg/L) > acetamiprid (2.7%, >LOQ, 0.08 µg/L) ≈ thiacloprid (2.7%, >LOQ, 0.14 µg/L). Approximately 92% of the subjects were found to be exposed to multiple neonicotinoids simultaneously. The mean, median, and maximum imidacloprid equivalent of the relative potency factor of NNIs were found to be 1.6, 0.5, and 22.52, respectively. The median estimated daily intakes of acetamiprid, imidacloprid, and nitenpyram were 0.47, 1.27, and 0.02 µg/kg/d for females and 0.91, 0.66, and 0.08 µg/kg/d for males, respectively. The maximum daily intakes of all the NNIs were <1% of their chronic reference doses (cRfDs), except for imidacloprid and thiacloprid which recorded maximum daily intakes corresponding to 17.97 and 8.28% of cRfDs, respectively. To the best of our knowledge, the present study is the first biomonitoring report on neonicotinoid insecticides in Africa. Environ Toxicol Chem 2021;40:2306–2318. © 2021 SETAC [ABSTRACT FROM AUTHOR]

Neonicotinoids are selective modulators of insect nicotinic acetylcholine receptors (nAChRs). These widely deployed insecticides interact with the orthosteric sites of nAChRs, not only to activate nAChRs on their own, but also to block the desensitizing component of nAChR responses. To date recombinant vertebrate or insect/vertebrate hybrid nAChRs have been deployed to understand the mechanism of selectivity and diversity of neonicotinoid actions as well as to show that both α/α and α/non‐α interfaces are involved in the interactions with neonicotinoids. However, many of the fine details of insecticide interactions with sites on nAChRs remain to be resolved. The breakthrough of functional expression of insect nAChRs allows such questions to be addressed, not only for neonicotinoids but for other insecticides targeting insect nAChRs. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Bradysia odoriphaga is a major insect pest that infests Chinese chive in northern China. Clothianidin is a second-generation neonicotinoid insecticide that is commonly used against B. odoriphaga. In this study, the effect of sublethal clothianidin concentrations (LC5 and LC10) on key biological characteristics of B. odoriphaga was investigated using an age-stage, two-sex life table method. Bioassays results showed that clothianidin exhibited high toxicity against B. odoriphaga with LC50 of 1.898 mg L−1 following 24 h exposure. The developmental duration of larvae was significantly increased when exposed to the LC5 (0.209 mg L−1) and LC10 (0.340 mg L−1) of clothianidin. No significant effects were observed on the pupal stage, adult pre-oviposition period (APOP), total pre-oviposition period (TPOP), and mean longevities of male and female. The oviposition period and fecundity of B. odoriphaga were reduced in clothianidin-treated groups. Moreover, key demographic parameters, including the intrinsic rate of increase (r), finite rate of increase (λ), and net reproductive rate (R0), were significantly decreased by the LC5 and LC10 of clothianidin, while no effects were noted on mean generation time (T). Overall, this study showed that sublethal concentrations of clothianidin have a detrimental effect on B. odoriphaga developmental period, fecundity, and life table parameters. Therefore, clothianidin has the potential to suppress the population of B. odoriphaga even at sublethal concentrations. [ABSTRACT FROM AUTHOR]

Neonicotinoid insecticides are the most widely used class of insecticides in the world and can have both lethal and sub‐lethal effects on non‐target organisms in agricultural areas. Monarch butterflies Danaus plexippus have experienced dramatic declines in recent decades and, given that a large proportion of milkweed on the landscape grows in agricultural areas, there is concern about the negative effects of neonicotinoids on this non‐target insect.In the field, we exposed common milkweed Asclepias syriaca, an obligate host plant of monarch butterflies, to agriculturally realistic levels of clothianidin, a widely used neonicotinoid insecticide. We tested whether this treatment influenced the number of eggs laid and larval survival over 2 years.Milkweeds were transplanted into 60 experimental plots alongside a corn crop planted with a clothianidin seed coat and 60 control plots alongside an untreated corn crop. The number of eggs, larvae at each stage (first to fifth instar), and the presence of other arthropods were recorded weekly from June to the end of August and survival from egg to fifth instar was estimated using a Bayesian state‐space statistical model.We counted more eggs in treated plots compared to control plots, suggesting a preference for treated milkweed. The number of plots with arthropods did not differ between treatments, but within treated plots, there was a greater decrease in the number of arthropods throughout the season. There was no evidence that monarchs selected plots with fewer arthropods for oviposition. Larval survival was lower in clothianidin‐treated plots compared to control plots.Our results suggest milkweed near clothianidin‐treated crops can reduce larval survival of monarch butterflies. While we provide some evidence that clothianidin could also act as an ecological trap for this species, further work is needed to identify additional components of fitness, including individual egg‐laying rates and survival beyond the pupal stage. Our findings add to a growing body of evidence that neonicotinoids can negatively affect non‐target organisms. ​ [ABSTRACT FROM AUTHOR]

A study was carried out to test the efficacy of chemicals and bio-rational insecticides against hopper Idioscopus spp. Infesting mango cv Amrapali. The treatments Thiamethoxam 25 WG 0.008% and clothianidin 50 WDG 0.0075% were found most effective against mango hopper. Moreover, acetamiprid 20 SP 0.01%, lambda-cyhalothrin 5 EC 0.003% and diafenthiuron 50 WP 0.05% were next effective treatments against mango hopper. The treatments like azadirachtin 10,000 PPM and L. lecanii (1x108 CFU/g) were found least effective against mango hopper. [ABSTRACT FROM AUTHOR]

Background and Objectives: The current study represents the first part of a Ph.D. research project conducted at The University of Guelph, Ontario, Canada in co-operation with the University of Babylon, Hilla – Iraq. The main objective of this part was to estimate the acute toxicity (LD 50) of clothianidin, imidacloprid (neonicotinoids), and carbaryl (Crabmeat) to honey bees. Method: The Three insecticides have been blamed for the colony collapse disorder (CCD) crisis, newly emerged adult bees were challenged orally and topically with a serial of doses of the three insecticides. Determination of the LD50 of each insecticide revealed that clothianidin was the most toxic insecticide to bees in oral and topical applications compared to the other two insecticides. The findings: The oral LD50 values were 0.004, 0.15, and 0.36 μg/bee for clothianidin, imidacloprid, and carbaryl respectively. The topical LD50 values were 0.034, 0.085, and 0.24 μg/bee for the three insecticides respectively Data were statistically analyzed by probit analysis using the US Environmental protection Agency statistical program (version 1-5). [ABSTRACT FROM AUTHOR]

A field experiment was carried out during rabi 2018-19 and 2019-20 at the experimental farm of Research Substation (Terai Zone) Kharibari, UBKV, Darjeeling, West Bengal to determine the Bio-efficacy of some newer insecticides against wheat aphids. The insecticide Acephate 50 + Imidacloprid 1.8 SP was found to be the most effective with 82.2% overall reduction of aphid population over control. The next effective insecticide was Imidacloprid 17.8% SL with 75.76% followed by Thiamethoxam 25 WG (70.02%), Clothianidin 50 WDG (67.53%) and Buprofezin 25 EC (61.14%) with respect to reduction of aphid population over control. [ABSTRACT FROM AUTHOR]

The investigations on "Management of white grub, H. consanguinea infesting groundnut (A. hypogea)" was conducted at Krishi Vigyan Kendra, Maulasar (Nagaur-II), Rajasthan, India during the Kharif 2019 and 2020 in the form of onfarm trials with T1- Farmer's Practice (Quinalphos @ 4 lit./ha) and T2- Improved technology (Pheromone (Methoxy benzene) traps 7-8/ha, seed treatment with clothianidin @ 2 g/kg seeds and drenching with imidacloprid 17.8 SL @ 300 ml/ha at 20-25 days after sowing). The results revealed that the Improved technology treatment comprising of Pheromone (Methoxy benzene) traps 7-8/ha, seed treatment with clothianidin @ 2 g/kg seeds and drenching with imidacloprid 17.8 SL @ 300 ml/ha at 20-25 days after sowing was found most effective against white grubs in groundnut. The improved technology (T2) recorded gross and net returns of Rs. 127756/- and Rs. 70340/- as against Farmer's Practice (T1) with gross and net returns of Rs. 104729/- and Rs. 50629/-, respectively over two years. The Improved technology (T2) recorded an incremental cost-benefit ratio of 2.22 as against Farmer's Practice (T1) with IBCR of 1.93. [ABSTRACT FROM AUTHOR]

Insect species richness and abundance has declined rapidly over the last few decades. Various stressors, such as the conversion of natural habitats, climate change, land-use intensification, agrochemicals and pathogens, are thought to be major factors in this decline. We treated female bees of two common pollinator species in Europe, Osmia bicornis and Bombus terrestris, with a field-realistic dose of the neonicotinoid clothianidin. We tested its effects on the foraging behavior of O. bicornis under semi-natural conditions and on the antennal sensitivity of both bee species to common floral volatiles by using electroantennography. Clothianidin negatively affected the foraging behavior in O. bicornis by decreasing the number of flowers visited per foraging flight and by increasing the time per flower visit and the searching time between two flowers. It also decreased the antennal sensitivity to 2-phenylethanol in the two bee species. Thus, clothianidin is clearly a threat for bees via its effects on their foraging behavior and antennal sensitivity and is hence probably detrimental for pollination and the reproductive success of bees.