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Chlorpyrifos has been used extensively for decades to control crop pests and disease-transmitting insects; its contribution to increasing food security and minimizing the spread of diseases has been well documented. Pymetrozine and Avermectin (also known as abamectin) have been used to replace the toxic organophosphate insecticides (e.g., Chlorpyrifos) applied to rice crops in China, where the overuse of pesticides has occurred. In addition, climate change has exacerbated pesticide use and pollution. Thus, farmers and communities are at risk of exposure to pesticide pollution. This study reviews the contamination, exposure, and health risks through environmental and biological monitoring of the legacy pesticide Chlorpyrifos and currently used insecticides Pymetrozine and Avermectin in China; it investigates whether changes in pesticide usage from Chlorpyrifos to Pymetrozine and Avermectin reduce pesticide contamination and health hazards to communities and residents. In addition, this review discusses whether Pymetrozine and Avermectin applications could be recommended in other countries where farmers largely use Chlorpyrifos and are exposed to high health risks under climate change scenarios. Although Chlorpyrifos is now banned in China, farmers and residents exposed to Chlorpyrifos are still experiencing adverse health effects. Local farmers still consider Chlorpyrifos an effective pesticide and continue to use it illegally in some areas. As a result, the concentration levels of Chlorpyrifos still exceed risk-based thresholds, and the occurrence of Chlorpyrifos with high toxicity in multiple environmental routes causes serious health effects owing to its long-term and wide application. The bioaccumulation of the currently used insecticides Pymetrozine and Avermectin in the environment is unlikely. Pymetrozine and Avermectin used in paddy water and soil for crop growth do not pose a significant hazard to public health. A change in pesticide use from Chlorpyrifos to Pymetrozine and Avermectin can reduce the pesticide contamination of the environment and health hazards to communities and residents. Finally, we recommend Pymetrozine and Avermectin in other countries, such as Vietnam, and countries in Africa, such as Ghana, where farmers still largely use Chlorpyrifos. [ABSTRACT FROM AUTHOR]

Chilo suppressalis Walker (Lepidoptera: Crambidae) is a devastating rice crop pest in China. Chemical insecticides have been used to effectively managing C. suppressalis field populations in most of China’s agricultural regions. However, due to the intensive and extensive application of these insecticides, C. suppressalis has developed widespread resistance to many active ingredients. Thus, insecticide resistance development is a genuine concern for all crop specialists and growers. In this study, using the topical application method, we assessed the susceptibility of forty-six field populations of C. suppressalis to three insecticides in three Central Chinese provinces from 2010 to 2021. Our findings revealed that field populations of C. suppressalis built moderate to high levels of resistance to triazophos (Resistance Ratio (RR) = 41.9–250.0 folds), low to moderate levels of resistance to chlorpyrifos (RR = 9.5–95.2 folds), with the exception of the Zhijiang population in 2013 and the Xinyang population in 2015 at 4.8 folds and 3.4 folds resistance rates, respectively, despite showing susceptibility, and low and moderate levels of resistance to abamectin (RR = 4.1–53.5 folds). There were significant correlations between the activity of the detoxification enzymes (CarE) and the log LD50 values of triazophos. These results should help effective insecticide resistance management strategies reduce the risk of rapid buildups of resistance to insecticides and slow down the process of selection for insecticide resistance. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology 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.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board 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.)

A method was developed for simultaneous determination of the residues of quizalofop-pethyl, chlorpyrifos, acetochlor amd imidacloprid in peanut by ultra high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The sample was purified with a combination of Nano-ZrO2, C18 and multi-walled carbon nanotubes (MWCNT), detected by UPLC-MS/MS, and quantified by external standard method. The results showed that in the range of 0.001- 0.5 mg/L, the linear relationship between the mass concentrations of the 4 pesticides and their corresponding peak areas was good, with r≥0.998 6. At the three spike levels of 0.01, 0.1 and 1 mg/kg, the average recoveries of the four pesticides in peanuts were between 82% and 109%. And the relative standard deviations (RSDs, n = 5) were between 2.8% and 9.0%. Among them, the limit of quantification (LOQ) was 0.01 mg/kg. This method was used to test 10 batches of peanut samples collected from large supermarkets and agricultural markets in Tai'an City. The results showed that the residues of the four pesticides in all samples did not exceed the maximum residue limits set by China. This method has the advantages of good purification effect, simple and efficient operation, high sensitivity, good stability and strong versatility. It is suitable for the simultaneous detection of four pesticide residues in peanuts. [ABSTRACT FROM AUTHOR]

BACKGROUND: Pesticides have been widely used to control pests on agricultural products in China, and large amounts of pesticide residues have caused a serious threat to human health. Thus, developing a high‐efficiency pesticide degradation method for fresh vegetables represents a great challenge. The present study investigated the effects of dielectric barrier discharge (DBD) plasma on the degradation of malathion and chlorpyrifos in aqueous solutions and on lettuces. RESULTS: DBD treatment significantly degraded malathion and chlorpyrifos in water and on lettuce. After cold plasma treatment at 80 kV for 180 s, the degradation efficiency of malathion (0.5 μg mL−1) and chlorpyrifos (1.0 μg mL−1) in aqueous solutions reached 64.6% and 62.7%, respectively. The degradation intermediates were explored by HPLC‐mass spectrometry and the DBD plasma degradation pathways of malathion and chlorpyrifos were proposed. There was no significant damage to the quality of lettuces, including color and chlorophyll content, after plasma treatment. Ascorbic acid decreased significantly during long‐term treatment with DBD plasma. To ensure the quality of lettuces during processing, the treatment time was shortened to 120 s. Under this condition, the degradation efficiency of malathion (0.5 mg kg−1) and chlorpyrifos (1.0 mg kg−1) on lettuces was found to be 53.1% and 51.4%. More importantly, we noted that cold plasma treatment significantly inactivated the microorganisms on lettuces. CONCLUSION: The results of the present study show that cold plasma is an effective and safe method for the degradation of organic pesticide residues on fresh vegetables at the same time as retaining the original quality. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

This study investigated the spatial distributions and seasonal variations of 19 CUPs in the coastal areas of the Shandong Peninsula and its surrounding rivers and assessed their ecological risk. In freshwater and seawater, insecticides (chlorpyrifos, methoxychlor, and pyridaben), as well as fungicides (fenarimol) and herbicides (dichlobenil) were the main pollutants (Detection Frequency: 100 %). Spatially, during winter, the regional pollution levels of Σ 19 CUPs in seawater showed a trend of Laizhou Bay (LZB, mean:4.13 ng L -1 ) > Yellow River Estuary (YRE, mean:2.57 ngL -1 ) > Bohai Bay (BHB, mean:2.21 ng L -1 ) > Yanwei Area (YWA, mean:1.94 ng L -1 ). The similarities of major substances between rivers and the marine environment suggest that river discharge is the main source of CUPs pollution in coastal areas. In summer, CUPs in rivers posed a high risk. In winter, the risk significantly decreased, indicating a moderate overall risk. Seawater exhibited a low risk in winter., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The green plant bug Apolygus lucorum is a major pest of Bacillus thuringiensis cotton in China. Previously, we reported that chlorpyrifos resistance in a laboratory‐selected strain of A. lucorum (BZ‐R) is associated with the homozygosis of an allele in the ace‐1 gene encoding an alanine to serine substitution at position 216 of acetylcholinesterase‐1. Here we describe the results of crosses between the resistant BZ‐R strain (41‐fold to chlorpyrifos) and the unselected susceptible BZ‐S strain homozygous for the wild type alanine allele at position 216. Resistance to chlorpyrifos was inherited as a semi‐dominant trait mainly controlled by a single autosomal gene and co‐segregates strongly but not completely with the serine substitution in ace‐1. Synergism bioassays and enzyme assays showed that minor contributions to resistance are also made by enhanced cytochrome P450 and carboxylesterase activities. A survey of 25 field populations from five Chinese provinces showed strong positive correlations between 50% lethal concentration against chlorpyrifos and S216 allele and genotype frequencies, although the most tolerant populations still only show 40%–50% S216 allele frequencies. The results above provide important information for designing effective resistance monitoring and management strategies for A. lucorum in China. [ABSTRACT FROM AUTHOR]

Chlorpyrifos is a type of organophosphate insecticide used extensively in the plantation of tomatoes, a worldwide popular food. However, chlorpyrifos residues on tomatoes bring risks to human health considering the consumption level of tomato is relatively high across many countries. Accurate detection and strict regulation of chlorpyrifos residues are very important in controlling health risks related to chlorpyrifos. Therefore, we developed a rapid, highly sensitive, economical, and nondestructive surface-enhanced Raman spectroscopy (SERS)-based method that can quantitatively determine the content of chlorpyrifos in tomatoes. Silver colloid was optimized and used as the enhance substrate for SERS. Chlorpyrifos residues on tomato surface and in tomato extract were both measured with SERS, and the results acquired under these practical conditions well matched those of chlorpyrifos standard solutions. Linear relationships between chlorpyrifos concentrations and SERS intensities at crucial characteristic peaks under both conditions were established, and the results showed linearity across the entire measured range from 10−3 to 10−9 mol L−1. The detection limit of the proposed method was 10−9 mol L−1, which was much lower than the standards of chlorpyrifos use for China, Japan and EU, and was the lowest reported concentration chlorpyrifos had been measured on any fruit/vegetable surface or in its extract. The proposed method was very promising in the accurate, quantitative detection of pesticide residues, and it may be adapted to a variety of agricultural products and other areas in food science. [ABSTRACT FROM AUTHOR]

Organophosphorus pesticides (OPPs) are a group of neurotoxic compounds that can cause neural dysfunction, overstimulation, paralysis, and even death to numerous non-target organisms. Despite their potential ecological impacts, there is a lack of research on water quality criteria (WQC) for OPPs, which hinders the risk assessment for these pollutants. This study aimed to derive short-term and long-term water quality criteria (SWQC and LWQC, respectively) for eight common OPPs through the species sensitivity distribution (SSD) methodology. The ecological risk of these compounds in aquatic environments was consequently assessed using a four-level tiered approach. The results showed that the derived SWQC ranged from 0.0245 μg/L (chlorpyrifos) to 18.6 μg/L (dimethoate), while the LWQC ranged from 0.326 ng/L (chlorpyrifos) to 0.354 μg/L (dimethoate). OPPs were widely recorded in different waters with concentrations up to 40.9 μg/L. The tiered approach results indicated that most OPPs had a low acute risk but a severe chronic risk. The estimated chronic hazard quotients (HQ) were calculated with a maximum of 4782, the exceedance probabilities with a maximum of 97.6%, and the overall probabilities (ORP) with a range of between 0.08% and 11.5%. These findings suggest that the contamination of OPPs in aquatic environments warrants further concern., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Current-use pesticides (CUPs) are widely applied in agriculture; however, little is known about their environmental behaviors, especially in the freshwater–seawater transitional zone. Water and sediment samples were collected in an intensively human impacted river (Xiaoqing River) from the headwaters to Laizhou Bay to investigate the distributions and environmental fates of four CUPs: trifluralin, chlorothalonil, chlorpyrifos, and dicofol. These CUPs were frequently detected in water and sediment samples. ∑CUPs in water and sediment samples ranged from 1.20 to 100.2 ng L−1 and 6.6–2972.5 ng g−1 dry weight (dw), respectively. Chlorpyrifos and chlorothalonil were the most abundant CUPs in water and sediment samples, respectively. Spatial distribution of CUPs in the Xiaoqing River aquatic ecosystem was mainly influenced by point sources, agricultural activities, the dilution effect by seawater, and environmental parameters. Field-based sediment water partitioning coefficients, normalized by organic carbon (log Koc), were calculated. Interestingly, temperature and salinity exhibited significant impacts on the distribution of log Koc of the four CUPs. The effect of temperature on the distribution of log Koc of the four CUPs varied between the CUPs. In most water samples, the levels of chlorpyrifos exceed the freshwater screening benchmarks. Hence, urgent control measures need to be devised and implemented. Image 1 • Four CUPs were firstly reported in the surface waters and sediments from a river-estuarine system. • Chlorpyrifos in water and chlorothalonil in sediment were the most abundant CUPs, respectively. • Field-based distribution coefficients (Kd and Koc) were estimated for the four CUPs. • Temperature and salinity were main factors influencing the CUP distribution coefficients. CUPs were ubiquitous detected in the river-estuary systems and temperature and salinity were main factors influencing their distribution coefficients. [ABSTRACT FROM AUTHOR]

Copyright of Research of Environmental Sciences is the property of Research of Environmental Sciences Editorial Board 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.)

Pesticides currently registered on the major nectar crops in China were reviewed. Then primary risk assessments of 61 insecticides registered on these nectar crops such as chlorpyrifos, imidacloprid and etc. to honey bees were conducted according to the existing risk assessment method. The results showed that among the 58 insecticides which were applied by spraying, the risk quotient (RQ) values of 35 insecticides were all greater than one, which meant the risk of these insecticides to honey bees was unacceptable. And among 6 systemic insecticides which were applied through soil or seed treatment, the RQ values of 5 insecticides were greater than one, which meant the risk to honey bees was unacceptable, and the only pesticide of this type which had low risk to bees was chlorantraniliprole. But it is noteworthy that the exposure assessments in the current assessment procedure was based on the maximum single application rates of the pesticides and the following issues was not considered: the degradation of pesticides in pollen, nectar, the washoff of pesticides from foliar, the relation between application time and the plant flowering period and etc. Therefore the assessment results were rather conservative. These findings can be treated as references for the reasonable usage and management of these insecticides and also suggest that the primary risk assessment procedure of pesticide to bees currently used in China could be refined. [ABSTRACT FROM AUTHOR]

The degradation of chlorpyrifos (CP) by an endophytic bacterial strain (HJY) isolated from Chinese chives (Allium tuberosumRottl. ex Spreng) was investigated. Strain HJY was identified asSphingomonassp. based on morphological, physiological, and biochemical tests and a 16S rDNA sequence analysis. Approximately 96% of 20 mg L−1CP was degraded by strain HJY over 15 days in liquid minimal salts medium (MSM). The CP degradation rate could also be increased by glucose supplementation. The optimal conditions for the removal of 20 mg L−1CP by strain HJY in MSM were 2% inoculum density, pH 6.0, and 30–35°C. The CP degradation rate constant and half-life were 0.2136 ± 0.0063 d−1and 3.2451 ± 0.0975 d, respectively, under these conditions, but were raised to 0.7961 ± 0.1925 d−1and 0.8707 ± 0.3079 d with 1% glucose supplementation. The detection of metabolic products and screening for degrading genes indicated thatO,O-diethylO-3,5,6-trichloropyridinol was the major degradation product from CP, while it was likely that some functional genes were undetected and the mechanism responsible for CP degradation by strain HJY remained unknown. Strain HJY is potentially useful for the reduction of CP residues in Chinese chives and may be used for thein situphytoremediation of CP. [ABSTRACT FROM PUBLISHER]

Water resources pollution by uncontrolled usage of pesticides is one of the most critical health and environmental problems. However, to protect the ecosystems and to design strategy plans, it is essential to obtain information on type and amount of pesticide residues in water resources. The present study presents an overview of two important pesticides: organo-chlorine and organo-phosphorus in world-water resources. Based on literature review, most of studies have been conducted in Asian countries, and the amount that have been reported in water resources in these countries was more than the permissible level. The high-level of δ-HCH (Lindane) pesticides in groundwater with concentration ∼82.21 μg/L was detected in China. In addition, the maximum measured concentration of Diazinon was detected in surface water in Iran with the value of ∼768.91 μg/L. The overview of the studies shows widespread presence of pesticides in water resources, and it was found that surface waters were more contaminated by pesticides. [ABSTRACT FROM PUBLISHER]

The resistance of the small brown planthopper (SBPH), Laodelphax striatella , to insecticides has been widely found in China, and has posed serious problems to efforts to control the pest. To determine the costs and benefits of resistance, the life tables of chlorpyrifos-resistant and -susceptible strains were constructed at 24 and 30 °C. The results showed the resistant SBPH (YN-CPF) had lower fitness at 24 °C, but slightly higher fitness at 30 °C compared to the susceptible SBPH. Transcriptomic analysis showed there are five heat shock protein genes changed their expression, and the up-regulated genes are LsHsc70-1 and LsHsc70-2 . The deduced amino acid sequences of LsHsc70-1 and LsHsc70-2 include three heat shock protein 70 (HSP70) family signatures, but LsHSC70-1 has the conserved HSP70 carboxyl terminal region of the “EEVD” motif, while LsHSC70-2 has the endoplasmic reticulum (ER) retention signal of the “KDEL” motif. The phylogenetic tree further identified LsHsc70-1 has closer evolutionary distances to cytoplasmic/nuclear HSP70s from human and Drosophila melanogaster , while LsHsc70-2 has closer evolutionary distances to HSP70s localized to ER. After treatment at 30–44°C, the expression of LsHsc70-1 and LsHsc70-2 was slightly increased in YN-CPF. These results suggested that LsHsc70-1 and LsHsc70-2 are members of Hsc70 family, localized to the cytosol/nucleus and ER, respectively. The up-regulated expression of these genes may protect the chlorpyrifos-resistant pest against damage under high temperatures, increasing its relative fitness, but the lower relative fitness of this population under optimal temperature may be the trade-off. [ABSTRACT FROM AUTHOR]

Chlorpyrifos, a broad−spectrum organophosphorus insecticide, has been widely detected worldwide and is a potential neurotoxin and endocrine disruptor. Besides, chlorpyrifos has been proven that have a negative effect on soil microbes. In the present study, chlorpyrifos formulation (LORSBAN®, 45% emulsifiable concentrate) was applied in an agricultural field at the recommended dose (R dose, 270.0 and 337.5 g a.i. ha−1 for wheat and maize respectively) and double recommended (DR) dose. Chlorpyrifos residue level and effect on soil microbes related to soil carbon and nitrogen cycle function were analyzed. Results showed that the half−lives of chlorpyrifos in wheat and maize field soil were 7.23–8.23 and 1.45–1.77 d, respectively. Application of chlorpyrifos at even DR dose did not result in unacceptable residual chlorpyrifos, where the final residual chlorpyrifos in wheat/maize (leaf, stem, and grain) was meet the requirement of the maximum residual limit (0.5 mg kg−1 for wheat and 0.05 mg kg−1 for maize) in China. Chlorpyrifos enhanced the activity of β −glucosidase by increasing the relative abundance of Sphingosinicella and promoted the carbon cycle in wheat field. The changes of cbbLR and cbbLG gene abundance also confirmed that chlorpyrifos could affect the import and export of soil carbon pool. The effect of chlorpyrifos on soil N cycle was determined by changes in the abundance of the bacterial genus Gemmatimonas , which is associated with denitrification. Further analysis of N−cycle functional genes and urease activity showed that chlorpyrifos inhibited nitrogen fixation in wheat field, but promoted nitrogen fixation in maize field. In general, bacterial abundance, urease, and AOA− amoA gene could be early warning markers of chlorpyrifos contamination. The results demonstrated the negative effects of chlorpyrifos on soil microbes especially on soil C and N cycle in actual agricultural field. It provides new insights about chlorpyrifos environmental pollution and its effect on soil ecosystems. [Display omitted] • Final residual chlorpyrifos in wheat or maize was below the maximum residue limit. • Chlorpyrifos formulation have negative effect on soil bacteria abundance. • Effect of chlorpyrifos on soil N cycle was related the genus Gemmatimonas. • Chlorpyrifos could affect the import and export of soil carbon pool. [ABSTRACT FROM AUTHOR]

Background: The extensive usage of pesticides has led to a ubiquitous exposure in the Chinese general population. Previous studies have demonstrated developmental neurotoxicity associated with prenatal exposure to pesticides., Objectives: We aimed to delineate the landscape of internal pesticides exposure levels from pregnant women's blood serum samples, and to identify the specific pesticides associated with the domain-specific neuropsychological development., Methods: Participants included 710 mother-child pairs in a prospective cohort study initiated and maintained in Nanjing Maternity and Child Health Care Hospital. Maternal spot blood samples were collected at enrollment. Leveraging on an accurate, sensitive and reproducible analysis method for 88 pesticides, a total of 49 pesticides were measured simultaneously using gas chromatography-triple quadrupole tandem mass spectrometry (GC-MS/MS). After implementing a strict quality control (QC) management, 29 pesticides were reported. We assessed neuropsychological development in 12-month-old (n = 172) and 18-month-old (n = 138) children using the Ages and Stages Questionnaire (ASQ), Third Edition. Negative binomial regression models were used to investigate the associations between prenatal exposure to pesticides and ASQ domain-specific scores at age 12 and 18 months. Restricted cubic spline (RCS) analysis and generalized additive models (GAMs) were fitted to evaluate non-linear patterns. Longitudinal models with generalized estimating equations (GEE) were conducted to account for correlations among repeated observations. Weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) were applied to examining the joint effect of the mixture of pesticides. Several sensitivity analyses were performed to assess the robustness of the results., Results: We observed that prenatal exposure to chlorpyrifos was significantly associated with a 4 % decrease in the ASQ communication scores both at age 12 months (RR, 0.96; 95 % CI, 0.94-0.98; P < 0.001) and 18 months (RR, 0.96; 95 % CI, 0.93-0.99; P < 0.01). In the ASQ gross motor domain, higher concentrations of mirex (RR, 0.96; 95 % CI, 0.94-0.99, P < 0.01 for 12-month-old children; RR, 0.98; 95 % CI, 0.97-1.00, P = 0.01 for 18-month-old children), and atrazine (RR, 0.97; 95 % CI, 0.95-0.99, P < 0.01 for 12-month-old children; RR, 0.99; 95 % CI, 0.97-1.00, P = 0.03 for 18-month-old children) were associated with decreased scores. In the ASQ fine motor domain, higher concentrations of mirex (RR, 0.98; 95 % CI, 0.96-1.00, P = 0.04 for 12-month-old children; RR, 0.98; 95 % CI, 0.96-0.99, P < 0.01 for 18-month-old children), atrazine (RR, 0.97; 95 % CI, 0.95-0.99, P < 0.001 for 12-month-old children; RR, 0.98; 95 % CI, 0.97-1.00, P = 0.01 for 18-month-old children), and dimethipin (RR, 0.94; 95 % CI, 0.89-1.00, P = 0.04 for 12-month-old children; RR, 0.93; 95 % CI, 0.88-0.98, P < 0.01 for 18-month-old children) were associated with decreased scores. The associations were not modified by child sex. There was no evidence of statistically significant nonlinear relationships between pesticides exposure and RRs of delayed neurodevelopment (P nonlinearity  > 0.05). Longitudinal analyses implicated the consistent findings., Conclusion: This study gave an integrated picture of pesticides exposure in Chinese pregnant women. We found significant inverse associations between prenatal exposure to chlorpyrifos, mirex, atrazine, dimethipin and the domain-specific neuropsychological development (i.e., communication, gross motor and fine motor) of children at 12 and 18 months of age. These findings identified specific pesticides with high risk of neurotoxicity, and highlighted the need for priority regulation of them., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Lack of knowledge on the destiny of organic micropollutants (OMPs) in the Tibetan Plateau region of China prevents the public from being aware of the need for protecting these unique aquatic ecosystems that are precious water resources and source areas of the Yellow River. To address this knowledge gap, this study systematically investigated the multi-residue analysis, distribution, and potential risks of six types of OMPs, namely, neonicotinoid pesticides (NEOs), fungicides, organophosphate esters (OPEs), organophosphorus pesticides (OPPs), psychoactive substances (PSs), and antidepressants (ADs), in surface waters of major cities in Qinghai. A total of 31 compounds, consisting of 8 NEOs, 1 fungicide, 12 OPEs, 2 OPPs, 5 PSs, and 3 ADs, were detected in >50% of the sites, showing their ubiquitous nature in the study area. Results showed that the total OMP concentration in surface water was 28.3-908 ng/L, and OPEs were the dominant composition (48.6%-97.4%). The risk quotient values of the detected diazinon and dursban regularly exceeded 1 for aquatic organisms at all sampling sites, indicating moderate-high chronic ecological risk. The joint probability curves showed that dursban and NEOs have higher risk levels than other OMPs. Although the results of the non-carcinogenic total hazard quotient of the OMPs in the surface water was less than 1 in all age groups and the carcinogenic risk was lower than the negligible risk level, the potential risks to children and infants were considerably greater and should not be underestimated. In addition to pollutant concentration and exposure duration, ingestion rate and body weight (BW) are also important factors affecting health risk, with BW having a negative effect. To the best of the authors' knowledge, this report is the first to describe OMP pollution in Qinghai, and the results provide new insight into the ecological security of the water resources of the Tibetan Plateau., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The mirid bug is frequently controlled by the application of organophosphorus insecticides in the transgenic Bt cotton field of China. A topical bioassay method was performed to evaluate the toxicities of chlorpyrifos and malathion towards field-collected Chinese populations of Apolygus lucorum from transgenic Bt cotton fields. For chlorpyrifos, the resistance ratios ranged from 0.8 to 9.4-fold compared to a susceptible strain. For malathion, the resistance levels relative to the susceptible strain ranged from 1.2 to 14.4-fold. Compared to a susceptible strain, the Cangzhou population from Hebei province showed the highest resistance ratios towards these insecticides. A comparison of the detoxifying and target enzyme activities between the Cangzhou population and a susceptible strain revealed that altered acetylcholinesterase possibly account for the chlorpyrifos and malathion resistance in the Cangzhou population. Two acetylcholinesterase (AChE-encoding) genes (designated Alace1 and Alace2 ) from the green mirid bug ( A. lucorum ) were identified. The Alace1 and Alace2 genes encoded 597 and 645 amino acids, respectively. Both AChE proteins had conserved motifs including a catalytic triad, a choline-binding site, and an acyl pocket. Quantitative real-time PCR analysis showed that Alace1 had a much higher transcriptional level than Alace2 , for the expression profiles of both spatial and time distributions. One amino acid substitution, Ala216Ser in Alace1, was found in the Cangzhou population. These results suggest that the mutation Ala216Ser should be most likely involved in organophosphorus resistance in A. lucorum . [ABSTRACT FROM AUTHOR]

The pesticide residue levels of three nuts (chestnut, walnut, pinenut) collected from seven main producing areas of China were investigated. Twenty-nine pesticides, including organophosphates (OPs), organochlorines (OCs), pyrethroids (PYs) and two fungicides (triadimefon and buprofezin) were analyzed by gas chromatography (GC). Four OPs (acephate, dimethoate, chlorpyrifos and parathion-methyl) were found in 11.4% samples, with the concentrations of 19.0 µg kg −1 to 74.0 µg kg −1 . Six OCs (DDT, HCH, endosulfan, quintozene, aldrin and dieldrin) were found in 18.2% samples, with the concentrations of 2.0 µg kg −1 to 65.7 µg kg −1 . Among OCs, p,p-DDE and α-HCH were the dominant isomer for DDT and HCH. Five PYs (fenpropathrin, fenvalerate, cypermethrin, bifenthrin and cyhalothrin) were found in 15.9% samples, with the concentrations of 2.5 µg kg −1 to 433.0 µg kg −1 . Fenpropathrin was the most frequently detected pesticide. In addition, triadimefon and buprofezin were detected only in two samples. For the tested nuts, 25.0% samples with multiple residues (containing more than two pesticides) were noted, even up to 9.1% samples with five pesticide residues. The residue of 15.9% samples was higher than the maximum residue limits (MRLs) of China. The short-term risks for the tested nuts were below 1.2%, and the highest long-term risk was 12.58%. The cumulative risk (cHI) for the tested pesticides were 8.43% (OPs), 0.42% (OCs), 12.82% (PYs) and 0.15% (fungicides), respectively. The total cHI was 21.82%. There was no significant health risk for consumers via nuts consumption. [ABSTRACT FROM AUTHOR]

Tea is the second widely consumed beverage next to water. Tea drinking is one of the important pathways for human exposure of organonphosphorus pesticide. Consequently, incidence of organonphosphorus pesticide residues and risk assessment should be clear. In this study, the level of organonphosphorus pesticide residues in 810 Chinese teas manufactured between 2010–2013 was investigated using gas chromatography coupled with tandem mass spectrometry and a flame photometric detector. Incidence of organonphosphorus pesticide residues occurred with a frequency of 29% and the average concentration of 93 μg kg−1. The residue levels varied from tea types, sale spots, and production area. Chlorpyrifos, isocarbophos, and triazophos were the only three organonphosphorus pesticides with detectable residues, and the detectable rates were 13.0%, 13.6%, and 17.4%, respectively. The corresponding average daily intake of chlorpyrifos, isocarbophos, and triazophos by tea drinking was 0.000083 μg kg−1bw day−1, 0.0036 μg kg−1bw day−1, and 0.0022 μg kg−1bw day−1. These results showed that the total hazard quotient of organonphosphorus pesticide pesticides from tea drinking was less than 0.02 and that the tea-drinking originated organonphosphorus pesticide exposure had a little adverse health effect for human being. [ABSTRACT FROM PUBLISHER]

The effects of two formulations (emulsifiable concentrate (EC) and granule (G)) on the distribution, degradation, sorption, and residue risk of chlorpyrifos (CHP) were investigated in two producing areas of bamboo shoot. The results showed that CHP was mainly distributed in the topsoil (0-5 cm, P < 0.05), with the proportion of CHP in the total quantity ranging from 76.0 to 100.0 % (G) and 12.0 to 98.1 % (EC), respectively. The degradation of CHP-EC in soils (half-life 27.7-36.4 days) was faster than that of CHP-G in soils (half life above 120-150 days). The main metabolite of CHP, 3,5,6-trichloro-2-pyridinol (TCP), was found in soil samples. CHP showed good sorption ability in the two tested soils, with the sorption coefficient (K) of 43.76 and 94.43 mg/kg. The terminal residues of CHP in bamboo shoots were in the range of 15.2-75.6 (G) and 10.4-35.7 μg/kg (EC), respectively. The soil type had a notable effect on the CHP behaviors in soil ( P < 0.05, especially for CHP-G), but it did not affect the metabolite of CHP. Although some positive bamboo shoot samples (CHP residue exceeding maximum residue limits) were found, the hazard quotients did not exceed 7 %, which meant there was a negligible risk associated with the exposure to CHP via the consumption of bamboo shoots. [ABSTRACT FROM AUTHOR]

Objective Residue risk assessment of pesticides in celery was conducted to provide a scientific basis for agricultural regulation policies and working procedures. Methods Three hundred samples from eight main growing regions in China were collected and pesticide residue analyses were performed using GC–MS/MS and LC-MS/MS methods. Both chronic and acute intake risk of pesticides were assessed. Furthermore, intake risk of each detected pesticide was ranked according to a predefined ranking matrix. Results (1) Out of these 300 samples, 175 were revealed to contain one or more pesticide residues. Twenty-five pesticides were identified in total, out of which, carbofuran was found to exceed the maximum residue limit. (2) Chronic and acute intake risks were evaluated and lie in between 0 and 1.80 and between 0.05 and 28.0 for these twenty-five pesticides, respectively. (3) Intake risk of individual pesticide was ranked; five pesticides, including avermectin, triazophos, chlorpyrifos, dimethoate oxygen, and carbofuran posed the highest risks. Conclusion Pesticide residues were detected in more than 58% celery samples in our study. Most pesticides have a residue level lower than their maximum residue limit and pose low chronic and acute dietary intake risk. However, usage of some pesticides like carbofuran should be closely monitored and regulated in the future. [ABSTRACT FROM AUTHOR]

Control of the beet armyworm, Spodoptera exigua depends heavily on chemical insecticides. Chlorpyrifos, an acetylcholinesterase (AChE) inhibitor, has been used in beet armyworm control for many years in China. Here we describe high level resistance to chlorpyrifos in a S. exigua strain, FX19-R, which was developed from a field-collected Chinese strain (FX) by selection with chlorpyrifos in the laboratory. FX19-R showed 1001-fold resistance to chlorpyrifos compared with the laboratory reference strain WH-S. The esterase inhibitor triphenyl phosphate (TPP) provided significant but small synergism (only 3.5-fold) for chlorpyrifos and neither of the glutathione s-transferase depletor diethyl maleate and the cytochrome P450s inhibitor piperonyl butoxide provided any detectable synergism, indicating that AChE insensitivity may play the major role in the resistance in FX19-R. Consistent with this, an amino acid substitution, F443Y (F331Y in standard Torpedo californica numbering) in AChE1 was identified in the FX19-R strain and shown to be tightly linked to chlorpyrifos resistance. Precisely homologous substitutions have been associated with organophosphate resistance in other pest species. A novel amino acid substitution, G311S (or G198S in standard numbering), was also identified in the reference strain WH-S. Recombinantly expressed AChE1 proteins carrying the G311S and F443Y substitutions were about 4.2-fold and 210-fold less sensitive to inhibition by chlorpyrifos oxon than wild-type AChE1, respectively. These results enhance our understanding of the mechanisms of chlorpyrifos resistance and provide a basis for resistance management based on monitoring the F443Y and G311S substitutions. [Display omitted] • FX19-R strain showed 1001-fold resistance to chlorpyrifos (CPS) compared with WH-S. • F443Y mutation in AChE1 is tightly linked to chlorpyrifos resistance in FX19-R. • Recombinant AChE1 (F443Y) was 210-fold less insensitive to CPS-oxon inhibition. • G311S mutation in AChE1 was identified in the reference strain WH-S. • Recombinant AChE1 with G331S was 4.2-fold less insensitive to CPS-oxon inhibition. [ABSTRACT FROM AUTHOR]

BACKGROUND To date, no research has been conducted to establish exposure levels for occupational pesticide operators under typical use scenarios in China. Through surrogate skin techniques (the whole-body method), the authors monitored dermal and inhalation exposure of pesticide applicators in China. In addition, the exposure of pesticide mixers was analysed. RESULTS The total dermal exposure of inexperienced and experienced applicators was respectively 4037 and 536 mg kg−1 of active ingredient ( AI) handled for application to maize that was <80 cm in height. The exposure level was highest on hands; the closer to the hands, the lower arms and the upper legs, the higher the exposure. The unit exposure of mixers differed according to the formulation; exposure to emulsifiable concentrate ( EC) and oil-in-water emulsion ( EW) was greater than exposure to wettable powder ( WP) or wettable dispersible granules ( WG). The unit exposure of mixers via inhalation was significantly greater than that of applicators when chlorpyrifos (48% EC) was used ( P < 0.0001). CONCLUSIONS The main objectives of this study were to provide an indication of the realistic exposure risk of mixers and applicators, and to contribute useful information for risk mitigation and management and epidemiological studies in China. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Highlights: [•] Chlorpyrifos and cypermethrin were frequently detected in the air in South China. [•] Peak atmospheric pesticide concentrations occurred in summer and fall. [•] Chlorpyrifos was mainly in the gas phase, while most pyrethroids were attached to particles. [•] Inhalation exposure risk to atmospheric current-use pesticides was negligible. [•] Infants, toddlers and children were more susceptible than adults to atmospheric CUPs. [ABSTRACT FROM AUTHOR]

Heavy metals and pesticides (HMPs) are common contaminants due to their extensive use worldwide. Diffusive gradients in thin films (DGT) are a good method for measuring the bioavailable concentration of pollutants. This study represents the first evaluation of HMP toxicity in aquatic biota using the DGT technique in sediments. Zhelin Bay was selected as the case study site because it has been contaminated by pollutants. Nonmetric multidimensional scaling (NMS) analysis reveals that a diverse range of pollutants (V, Cr, Ni, Cu, Zn, As, Se, InHg, Mo, Cd, Sb, W, Pb, CLP, PYR) are mainly influenced by sediment characteristics. Assessment of single HMP toxicity found that the risk quotient (RQ) values for Mn, Cu, inorganic Hg (InHg), chlorpyrifos (CLP) and diuron (DIU) are significantly higher than 1, indicating that the adverse effects of these single HMPs should not be ignored. The combined toxicity of HMP mixtures based on probabilistic ecotoxicological risk assessment shows that Zhelin Bay surface sediments had a medium probability (54.6%) of toxic effects to aquatic biota., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Ltd.)

The massive use of pesticides brings considerable environmental and human health impacts. This study conducted an overall assessment of the ecological impact of the extensive pesticide use in China from 1999 to 2018 through the Chemical Footprint (ChF) calculation. The results demonstrated that the primary ecological impacts caused by pesticides occurred in the most central and eastern regions in China, e.g., provinces of Shandong, Henan, Hubei, Anhui, and Jiangsu. The northeastern, some southern and central provinces, e.g., Heilongjiang, Jilin, Liaoning, Yunnan, Guangxi, Guangdong, Ningxia, and Shaanxi, got moderate impacts, whereas the northwest regions, e.g., Qinghai, Xinjiang, and Tibet, had much lighter impacts relatively. The agricultural soil in inland areas and surface sea waters in coastal provinces bore the major impacts of the pesticide pollution in China, shared above 80% of the ChF across all environmental compartments. Chlorpyrifos, pymetrozine, fenpropathrin, pyridaben, atrazine, etc., were the pesticides that had the greatest impacts on the ecosystem, which contributed over 95% of the total ChF of pesticides used in China, although the use amount of these pesticides accounted for less than 10% of the total use amount of all pesticides annually. The study also indicated that the overall ChF of pesticide use in China has been declining since 2010, which was corresponding with the control actions of highly hazardous pesticides, especially the elimination of high toxic organophosphorus insecticides during the past decade., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Highlights: [•] Resistance of these mites was demonstrated under laboratory bioassay conditions. [•] Mites collected from different regions had parallel resistance to the same insecticide. [•] The safety of insecticides to Amblyseius longispinosus was assessed. [•] The results were the first report of resistance of A. longispinosus in China. [ABSTRACT FROM AUTHOR]

ABSTRACT The present study intended to develop receptor-mediated luciferase reporter gene assays to evaluate and compare the estrogen receptor (ER), androgen receptor (AR) and thyroid hormone receptor (TR) activities of target chemicals. Di-2-ethylhexyl-phthalate (DEHP), chlorpyrifos (CPF), 2,4-dichlorophenoxyacetic acid (2,4-D) and bisphenol A (BPA) are some of the most common contaminants in drinking water and are frequently detected in China and worldwide. The chemicals were tested at concentrations of 0.1, 1, 10 and 100 times their maximum contaminant level in drinking water. The results showed that BPA possessed various activities on ER, AR and TR. DEHP and CPF could suppress 17 β-estradiol or testosterone activity with different potencies, and DEHP possessed weaker anti-thyroid hormone activity. 2,4-D showed no agonist or antagonist activity against these hormone receptors, but it significantly enhanced the activity of testosterone through AR. Furthermore, the mixture of DEHP and CPF exhibited stronger ER and AR antagonist activities than each single component alone, but their combined effects were less than the expected effects based on the additive model. These results implied that the transcription activation mediated by hormone receptors was the potential endocrine-disrupting mechanism of the test chemicals. Our study also provided useful tools for evaluation of their endocrine disrupting activity. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: The rice stem borer, Chilo suppressalis (Walker), an important insect pest of rice in China, has developed resistances to several classes of insecticides in field. In order to investigate multiple resistance mechanisms, synergistic tests were conducted with the Ruian (RA) population and Lianyungang (LYG) population, two representative populations to different insecticides. Results showed that diethyl maleate (DEM), S,S,S-tributyl phosphorotrithioate (DEF) and piperonyl butoxide (PBO), had no significant synergistic or inhibitory effect on the high level of resistance to monosultap (313.4-fold) and moderate level to chlorpyrifos (36.9-fold) in Ruian field population from the year 2011 (RA11). DEF significantly synergized the activity of triazophos in RA11 population (536.8-fold), with synergism ratio of 1.92. DEF and PBO significantly suppressed 43.3% and 40.4% of resistance to fipronil in RA11 population (48.4-fold), respectively, with the synergistic ratios of 1.76 and 1.69. When pretreated with PBO, the activity of deltamethrin against RA11 population were significantly synergized, with synergism ratio of 9.57, and with reducing resistance levels from 152.5- to 15.9-fold. The results of this study indicated that resistance to several classes of insecticide among the field populations of C. suppressalis might be provided by the combination of the multiple resistance mechanisms. Metabolic resistance mechanism might be the major reason for the evolution for resistance to deltamethrin and fipronil, while resistance to monosultap, triazophos and chlorpyrifos is not associated with metabolic resistance. [Copyright &y& Elsevier]

Chlorpyrifos (CPF) is one of the organophosphorus pesticides widely used around the world, especially in China. Acetylcholinesterase inhibition is the main effect of organophosphorus insecticides exposure. Studies showed that CPF may also interfere with the metabolism of monoamine transmitters. To investigate the effects of CPF on dopaminergic pathway, the dopamine content, gene expression of catechol-O-methyl- transferase (COMT), vesicular monoamine transporter-2 (VMAT-2), and monoamine oxidase (MAO) and its activity in PC12 cells exposed to CPF was determined. Results showed that cell viability was decreased and total dopamine concentration was increased with CPF administration in a dose-dependent pattern. Gene of MAO was significantly downregulated in PC12 cells, while genes of COMT and VMAT-2 in PC12 cells did not show any change after CPF exposure. The MAO activity was decreased following incubation exposed to CPF. These results suggest that CPF may interfere with dopaminergic pathway through inhibition on gene and protein expression of MAO in vitro. [ABSTRACT FROM AUTHOR]

The analytical method for the residues of chlorpyrifos in rice plants, water and soil was developed and dissipation of chlorpyrifos under field conditions was studied. The limit of detection (LOD) of chlorpyrifos was 0.006mgkg−1 and the limit of quantification (LOQ) was found to be 0.04mgkg−1 in rice plant (water) and 0.02mgkg−1 in the other substrates, respectively. The results showed that the initial residues of chlorpyrifos in Nanjing and Guangxi were 4.99 and 6.05mgkg−1 (rice plant), 1.35 and 1.58mgkg−1 (water) and 0.51 and 0.63mgkg−1 (soil), respectively. The half-lives of chlorpyrifos in rice plant, water and soil from Nanjing were 4.28, 0.58 and 1.35 day, respectively, and the half-lives of those from Guangxi were 3.86, 0.52 and 1.21 day, respectively. The husked rice, rice hull and straw samples were found to contain chlorpyrifos well below the maximum residue limit (MRL) following the recommended dosage, the residues of chlorpyrifos in soil were undetectable under all application levels and frequencies after 28 day of applications. [Copyright &y& Elsevier]

Abstract: Chlorpyrifos is a widely used organophosphorus insecticide in agricultural pest control. To understand the residue behavior of chlorpyrifos and to evaluate the dietary risk of chlorpyrifos residue in food in China, a number of residue studies were conducted on rice and cabbage. The supervised trial median residues (STMRs) for rice and cabbage were less than 0.010 and 0.227mgkg−1, respectively. Only 7.4% and 13.3% of acceptable daily intake (ADI) (0–0.01mgkg−1 bw) of chlorpyrifos is occupied by dietary daily intake to the Chinese adult and children, respectively, due to the consumption of rice and cabbage. These results on risk assessment were consistent with that of JMPR. Incorporation of market survey residue data gave a 5-fold reduction in the estimated exposures to chlorpyrifos. Concerning the acute exposure, the national estimated short-term intake (NESTI) represents 0.077% and 10.6% for rice and cabbage, respectively, of the acute reference dose (ARfD) (0–0.1mgkg−1 bw). The application of chlorpyrifos at the recommended dose on rice and cabbage is unlikely to pose any public health issues if it is applied according to the good agricultural practices (GAPs) established by each country. [Copyright &y& Elsevier]

Chinese cabbage, Brassica chinensis L., and cabbage, Brassica oleracea L. var. capitata, are the main daily foliar vegetables of the vast majority of the population of eastern and southern China. Cabbages are also planted and consumed widely in other countries. The insecticide and acaricide chlorpyrifos is registered in many countries. Chlorpyrifos controls a variety of insects in plants and soils, and chlorpyrifos is extensively used in the Chinese market. Food poisoning due to the presence of organophosphorus pesticide residues in vegetables has been reported in China provinces. Plant uptake of pesticide residues in air, water, and soil is a source of pesticide residues in vegetables. Here, phytotoxicity and uptake of chlorpyrifos by Chinese cabbage and cabbage were studied in the laboratory using the batch technique. From 0 to 16 days after chlorpyrifos treatment, vegetables roots, stems, leaves, and culture water samples were collected, and the residues of chlorpyrifos in culture water, plant tissues were analyzed using GC-FPD. The results demonstrate that culture solutions with chlorpyrifos had no significant inhibitory effects on vegetable plant height. However, at 1.0 mg/l, it had significant inhibitory effects on the root length and fresh weight of Chinese cabbage. Then, at 10.0 mg/l, it had only significant inhibitory effects on the root length and fresh weight of cabbage compared to the control treatment. The disappearance rates of chlorpyrifos in solutions were in sequence as: nutrition solution with Chinese cabbage, nutrition solution with cabbage, pond water, nutrition solution. The results showed also that chlorpyrifos can be taken up by roots of Chinese cabbage and cabbage from water and subsequently translocated as a function of time. Uptake dynamics of chlorpyrifos from culture solutions by the two cabbage plants were similar. [ABSTRACT FROM AUTHOR]

Abstract: Heavy metal and pesticide contamination has previously been reported in Chinese Herbal Medicines (CHMs), in some cases at potentially toxic levels. This study was conducted to determine general patterns and toxicological significance of heavy metal and pesticide contamination in a broad sample of raw CHMs. Three-hundred-thirty-four samples representing 126 species of CHMs were collected throughout China and examined for arsenic, cadmium, chromium, lead, and mercury. Of the total, 294 samples representing 112 species were also tested for 162 pesticides. At least 1 metal was detected in all 334 samples (100%) and 115 samples (34%) had detectable levels of all metals. Forty-two different pesticides were detected in 108 samples (36.7%), with 1 to 9 pesticides per sample. Contaminant levels were compared to toxicological reference values in the context of different exposure scenarios. According to a likely scenario of CHM consumption, only 3 samples (1%) with heavy metals and 14 samples (5%) with pesticides were found with concentrations that could contribute to elevated background levels of contaminant exposure. According to the most conservative scenario of CHM consumption, 231 samples (69%) with heavy metals and 81 samples (28%) with pesticides had contaminants that could contribute to elevated levels of exposure. Wild collected plants had higher contaminant levels than cultivated samples. Cadmium, chromium, lead, and chlorpyrifos contamination showed weak correlations with geographic location. Based on our assumptions of the likely mode of consumption of raw CHMs, the vast majority (95%) of the 334 samples in this study contained levels of heavy metals or pesticides that would be of negligible concern. However, given the number of samples with detectable contaminants and the range between the more likely and more conservative scenarios of contaminant exposure, more research and monitoring of heavy metals (especially cadmium and chromium) and pesticide residues (especially chlorpyrifos) in raw CHMs are advised. [Copyright &y& Elsevier]

Triazophos and chlorpyrifos are organophosphorus pesticides (OPs), and their primary hydrolytic metabolites are 1-phenyl-3-hydroxy-1,2,4-triazole (BZC) and 3,5,6-trichloro-2-pyridinol (TCP). In this study, the adsorption and degradation of triazophos, chlorpyrifos, BZC and TCP were investigated in paddy soil from Chaohu Lake, China. Adsorption tests demonstrated that the adsorption of these compounds to soils could be described by the Freundlich equation. Moreover, chlorpyrifos displayed the highest affinity for adsorption, followed by triazophos, BZC and TCP. Degradation of these compounds in non-sterile soil followed first-order exponential decay kinetics, and the half-life (t 1/2) of these contaminants ranged from 8.40 to 44.34 d. Sterilization of soil decreased the degradation rate, indicating that microorganisms played a significant role in the degradation of these compounds. The values of t 1/2 and K oc were fitted to obtain models that could predict the leaching potential of the contaminants from soil. Compared to their parent compounds, BZC and TCP showed high potential for leaching into groundwater. The inoculation of OPs-degrading bacterium (Diaphorobacter sp. GS-1) removed 95.38%, 100% and 100% of triazophos, chlorpyrifos and BZC in paddy soil after 21 d, respectively. The pollution risk of triazophos, chlorpyrifos and BZC could be greatly decreased by inoculating soil with Diaphorobacter sp. GS-1, which decreases the t 1/2 of the contaminants. [Copyright &y& Elsevier]

Abstract: Sediment-associated pesticides, including organochlorine (OCP), organophosphate (OP), and pyrethroid insecticides, were analyzed in urban waterways in three cities (Guangzhou, Dongguan, and Shenzhen) in the Pearl River Delta (PRD), China. The OCPs represented 27.2% of the detectable insecticides in sediment, and chlordanes, DDTs, and endosulfans were the most frequently detected OCPs. The currently used insecticide chlorpyrifos was the only OP detected above the reporting limit (RL), with concentrations ranging from

The article presents a study on the resistance management technique of Laodelphax striatellus, also known as Fallén. The study uses bioassays, enzyme assays, and protein assays in the susceptible strain of L. striatellus with chlorpyrifos collected from Yunnan Sheng, China in July 2001. Furthermore, the results show that the susceptible strain has resistance to chlorpyrifos, and susceptible and selected strains have no significant difference in the metabolic enzyme activities.

No abstract available. [ABSTRACT FROM AUTHOR]

[Display omitted] • GA-PLS, UVE-PLS, VCPA-PLS and CARS-PLS were comparatively investigated for CP detection. • CARS-PLS model achieved optimum results, the RPD was 4.87. • A SERS-based method for CP was developed with a LOD of 0.01 μg/mL. • The LODs found were lower than the People's Republic of China set the standard of CP in pollution-free rice. Due to the continuous development and progress of society and more and more attention to the quality and safety of food, rapid testing of pesticides in food is of great significance. In this paper, surface-enhanced Raman spectroscopy (SERS) and chemometric algorithms were employed collectively to quantify chlorpyrifos (CP) residues in rice samples. The SERS spectra from different concentrations (0.01–1000 μg/mL) of CP were collected using AgNPs-deposited-ZnO nanoflower (NFs)-like nanoparticles (Ag@ZnO NFs) SERS sensor. Four quantitative chemometric models for CP were comparatively studied, and the competitive adaptive reweighted sampling-partial least squares model achieved the best prediction and practical applicability for predicting CP levels with a limit of detection of 0.01 µg/mL. The results of the student's t -test showed no significant difference between this method and high-performance liquid chromatography (HPLC), and good relative standard deviation (RSD) indicated that this method could be used for the detection of CP in rice. [ABSTRACT FROM AUTHOR]

The fungicide carbendazim and the insecticide chlorpyrifos are frequently used together to protect various fruit and vegetable crops in China. At high doses, carbendazim is a known carcinogen while chlorpyrifos has neurotoxic potential, but the combined toxicity of these two compounds has not been systematically investigated. In this study, we examined the separate and combined effects of these compounds on zebrafish embryonic development. The LC 50 values for carbendazim and chlorpyrifos at 96 h post-fertilization (hpf) were 0.89 mg/L and 3.83 mg/L, respectively. Carbendazim dose-dependently increased the spontaneous tail-wagging frequency of 24 hpf embryos, the hatching rate of 48 hpf embryos, and the mortality and deformity rate of 96 hpf embryos, while chlorpyrifos increased the heart rate of 48 hpf embryos as well as the mortality and deformity rate of 96 hpf embryos. Mixed exposure at an equipotent concentration ratio (Mix1) and at the ratio of maximum residue limits for typical fruits (apples) (Mix2) revealed significant synergistic effects on lethality at 96 hpf within the 0%–90% effect levels range. In contrast, there was an antagonistic effect of the equipotent concentration ratio on lethality in the 90%–100% concentration range, while the ratio at the maximum residue limits still showed a synergistic effect. Mix1 exhibited antagonism on hatching rate in the 0%–35% range and synergy in the 40%–100% range, while Mix2 had a synergistic effect on hatching rate in the 0%–35% range, an additive effect at 40%, and an antagonistic effect at >40%. Both mixtures had a synergistic effect on deformity rate over all concentration ranges. Carbendazim and chlorpyrifos demonstrate synergistic developmental toxicity, indicating that health and environmental risk assessments should be conducted for various combinations of these agents. • We examined carbendazim and chlorpyrifos toxicity in zebrafish embryos. • Both pesticides dose-dependently disrupted embryonic development. • In combination, toxicity was primarily synergistic across dose ranges and ratios. • Comprehensive health risk evaluation must consider these complex combined effects. [ABSTRACT FROM AUTHOR]

Temporal and spatial distribution of organochlorine pesticides (OCPs) and the organophosphate pesticide chlorpyrifos, one of the main insecticides used in Argentina, was evaluated in two populations of the sea anemone Bunodosoma zamponii living under different anthropological stressors: Las Delicias (LD) adjacent to a wastewater plant, and Punta Cantera (PC) a reference site. Pesticides were analyzed throughout the year in water, sediments and whole organisms. Chlorpyrifos represented 50% of the total pesticide found in water samples during winter. HCHs and drins were predominant in sediment samples, mainly in LD. Total pesticide concentration in anemones from LD was higher than those from PC during winter (mainly associated with HCHs, endosulfans, DDTs and chlorpyrifos levels), coincident with the main period of effluent discharge to the coast after pesticide applications and also the rainiest season. Dissimilarities among anemones populations could stem from a differential input of pesticides in each site and/or a contrasting physiological status of the populations., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Simple Summary: As an important enzyme system in organisms, P450 multi-functional oxidase not only participates in the metabolism and synthesis of substances in organisms but can also maintain the normal physiological functions of organisms under stress. As one of the important rice pests, the harm caused by white-backed planthoppers has been increasing in recent years. Although the application of chemical pesticides as one of the prevention and control measures can slow down the harm of white-backed planthoppers, its resistance is also rising rapidly. Among them, the generation of metabolic resistance dominated by the P450 enzyme is more common. In this study, we measured the expression of ten P450 gene in vivo situations with a background of chlorpyrifos resistance in white-backed planthoppers. After selecting the two genes with the highest expression, the function of these two genes in the pesticide resistance process was verified by RNA interference and provided a theoretical basis for a follow-up study of the molecular mechanism of the P450 gene mediated by pesticide resistance formation. The white-back planthopper (WBPH), Sogatella furcifera, mainly harms rice and occurs in most rice regions in China and Asia. With the use of chemical pesticides, S. furcifera has developed varying degrees of resistance to a variety of pesticides. In our study, a chlorpyrifos-resistant population (44.25-fold) was built through six generations of screening with a sublethal dose of chlorpyrifos (LD50) from a field population. The expression levels of ten selected resistance-related P450 genes were analyzed by RT-qPCR and found that CYP408A3 and CYP6CS3 were significantly more expressed in the third instar nymphs of the XY17-G5 and XY17-G6 populations, about 25-fold more than the Sus-Lab strain, respectively (p < 0.01). To elucidate their molecular function in the development of resistance towards chlorpyrifos, we cloned two P450 full lengths and predicted their tertiary protein structures. CYP408A3 and CYP6CS3 were also downregulated after injecting dsCYP408A3, dsCYP6CS3, or their mixture compared to the control group. Moreover, the mortality rates of the dsCYP6CS3 (91.7%) and the mixture injection treatment (93.3%) treated by the LC50 concentration of chlorpyrifos were significantly higher than the blank control group (51.7%) and dsCYP408A3 injection treatment (69.3%) at 72 h (p < 0.01). Meanwhile, the P450 enzyme activities in the dsRNA treatments were lower than that in the control (XY17-G6) (p < 0.01). Therefore, the P450 gene CYP6CS3 may be one of the main genes in the development of chlorpyrifos resistance in S. furcifera. [ABSTRACT FROM AUTHOR]

Organophosphate pesticides (OPPs) are one type of the most massively used pesticides and ubiquitously detected in aquatic environments, which may pose potential risks to the aquatic organisms and human health. In the present study, the spatiotemporal distribution and potential risks of OPPs were investigated in overlying water and surficial sediments from urban waterways of Guangzhou. For all studied sites, in general, four target OPPs (i.e., malathion, chlorpyrifos, terbufos, and diazinon) were present in the overlying water, with malathion and chlorpyrifos as major components. Higher concentrations of the four OPPs were found for the water and sediments collected in the dry season compared to the wet season, possibly because of the dilution effect of heavy rains. The results of Pearson's analyses and principal coordinate analyses (PCoA) suggested similar sources for target OPPs in the water and sediments across the Guangzhou urban waterways. Potential ecological risks of the OPPs to three representative taxons (algae, aquatic invertebrates, and fish) were evaluated via toxic units (TUs) and risk quotients (RQs), while risk assessment on human health was performed using hazard index (HI). Although TU results showed no acute risks to the aquatic organisms in the overlying water and surface sediments, RQ results of the mixture showed high risks to the aquatic invertebrate and fish in all water samples. Individual HI values and cumulative HI values were on the order of 10 -6 -10 -3 for children and adults, suggesting no potential risks to either children or adults through drinking and bathing., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Soybean pod borer (Leguminivora glycinivorella) is an important pest in soybean production, and chemical pesticides was major way for prevention. However, it is difficult to balance the efficiency and safety of pesticide application. In this paper, we evaluated safety and effectiveness of common insecticides (chlorpyrifos and lambda-cyhalothrin) on soybean from three aspects, including distribution, dissipation and control effect, around three major soybean production area (Anhui, Jilin and Shandong) in China. For chlorpyrifos, the initial deposition of each position (upper leaf, lower leaf, upper stem, lower stem, soybean and root) was determinated for 0.23 mg/kg to 70.7 mg/kg, and the half-lifes ranged from 1.96 days to 5.36 days. For lambda-cyhalothrin, the initial deposition of the position was determinated for 0.10 mg/kg to 2.54 mg/kg, and the half-lifes ranged from 2.45 days to 7.26 days. We found that the target insecticides were major deposition and faster degradation in upper stem and leaf. Through comparing the relationship between field control effect and residue, it can be suggested that 40% chlorpyrifos EC and 2.5% lambda-cyhalothrin WE should be sprayed at 600 g a.i./ha and 5.63 g a.i./ha for SPB prevention. This study enhanced our understanding of distribution, dissipation and relationship between residue and control effect. The results provided data support for guiding the precise and scientific application of chemical insecticides on soybean. • The chlorpyrifos and lambda-cyhalothrin were major residue in upper leaf of soybean. • The chlorpyrifos and lambda-cyhalothrin descend more faster in upper leaf and stem. • For prevention of Soybean pod borer, the chlorpyrifos and lambda-cyhalothrin should be sprayed at the dose of 600 g a.i./ha and 5.63 g a.i./ha. [ABSTRACT FROM AUTHOR]

• Neonicotinoids and dialkylphosphates were measured in urine from nine countries. • The highest sum concentration of 14 neonicotinoids was found in Vietnam (12.2 ng/mL). • The highest sum concentration of six dialkylphosphates was found in China (18.4 ng/mL). • Dimethyl phosphates accounted for 51–89% of the total concentrations. • Daily exposure dose to organophosphates was highest in China (515 μg/day). The application of neonicotinoid insecticides (neonics) has increased dramatically as a replacement for organophosphate pesticides (OPs) in recent years. Nevertheless, little is known about human exposure to these pesticides in various countries. In this study, concentrations of 14 neonics and six dialkylphosphate metabolites (DAPs) were determined simultaneously in 566 urine samples collected from nine countries during 2010–2014. The highest sum concentration of 14 neonics was found in urine from Vietnam (median: 12.2 ng/mL) whereas that of six DAPs was from China (18.4 ng/mL). The median concentrations of ∑6 DAPs were twice higher than those of ∑14 neonics across the nine countries, which suggested a greater exposure to OPs than neonics. The overall pattern of urinary pesticide concentrations was similar among the nine countries with dimethylphosphate (DMP) and dimethylthiophosphate (DMTP) accounting for 51–89% of the total pesticide concentrations. Differences in urinary pesticide concentrations between genders (female and male), age groups (≤20, 21–49, and ≥50 years), and regions (cities of Shanghai, Guangzhou and Qiqihar) were examined. Total daily exposure doses to OPs were highest in China (515 μg/day) with 15% of the samples exceeding the U.S. Environmental Protection Agency's reference dose for chlorpyrifos (18 μg/day). This is the first study to establish baseline levels of OP and neonics exposure in general populations across nine countries. [ABSTRACT FROM AUTHOR]

Chlorpyrifos is one of the most heavily used pesticides in domestic and agricultural insect prevention globally. Given the potential neurotoxicity of chlorpyrifos and its high detection rates in food and drinking water, health risks attributable to chlorpyrifos residue in Chinese drinking water and food in both China and Denmark were assessed in this study. Mixed left-censored handling models were used to deal with the non-detected values in chlorpyrifos concentrations. Results show that chronic exposure imputed to chlorpyrifos residue is much lower than the reference dose, and will thus not pose appreciable health risk to the consumer. Compared to the total exposure from chlorpyrifos in drinking water and food sources, chronic exposure from drinking water sources in China accounts for 0–4.4%. Health risk owing to chlorpyrifos in food within China is 6-7-fold higher than in Denmark, and this coincides with the fact that all application of chlorpyrifos is banned in Denmark, in contrast to China. However, the Danish consumers are still exposed from imported food items. The main health risk contributors in China are the food groups of Grains and grain-based products and Vegetable and vegetable products, while the main chronic health risk contributor in Denmark is the food group of imported fruit and fruit products. Image 1 • Whether to ban chlorpyrifos in the world is a controversial question. • Chronic health risk of chlorpyrifos in China and Demark by oral intake is compared. • Mixed left-censored handling models were used to deal with the non-detected values. • The health risks in Danish foods are mainly attributable to imported fruits. • The HQ for chlorpyrifos in Chinese food is 6-7-fold higher than in Danish food. Chronic exposure due to chlorpyrifos residue in food in China is 6-7-fold higher than in Denmark. [ABSTRACT FROM AUTHOR]