Pesticide Regulation Research Articles

Predictors of pesticide levels in carpet dust collected from child care centers in Northern California, USA

BackgroundYoung children may be exposed to pesticides in child care centers, but little is known about determinants of pesticide contamination in these environments.ObjectiveCharacterize pesticide contamination in early care and education (ECE) centers and identify predictors of pesticide concentrations and loading in dust collected from classroom carpets.MethodsCarpet dust samples were collected from 51 licensed child care centers in Northern California and analyzed for 14 structural and agricultural pesticides. Program characteristics were collected through administration of director interviews and observational surveys, including an integrated pest management (IPM) inspection. Pesticide use information for the prior year was obtained from the California Department of Pesticide Regulation to characterize structural applications and nearby agricultural pesticide use.ResultsThe most frequently detected pesticides were cis-permethrin (98%), trans-permethrin (98%), bifenthrin (94%), fipronil (94%), and chlorpyrifos (88%). Higher bifenthrin levels were correlated with agricultural applications within 3 kilometers, and higher fipronil levels were correlated with professional pesticide applications in the prior year. In multivariable models, higher IPM Checklist scores were associated with lower loading of chlorpyrifos and permethrin. Placement of the sampled area carpet was also a predictor of chlorpyrifos loading. The strongest predictor of higher pesticide loading for the most frequently detected pesticides was location in California’s San Joaquin Valley.SignificanceOur findings contribute to the growing understanding that pesticides are ubiquitous in children’s environments. Pesticide levels in carpet dust were associated with some factors that ECE directors may have control over, such as IPM practices, and others that are beyond their control, such as geographic location. IPM is an important tool that has the potential to reduce pesticide exposures in ECE environments, even for pesticides no longer in use.ImpactOne million children in California under six years old attend child care programs where they may spend up to 40 h per week. Children are uniquely vulnerable to environmental contaminants; however early care settings are under researched in environmental health studies. Little is known about predictors of pesticide levels found in environmental samples from child care facilities. This study aims to identify behavioral and environmental determinants of pesticide contamination in California child care centers. Findings can empower child care providers and consumers and inform decision makers to reduce children’s exposures to pesticides and promote lifelong health.

Using National Agricultural Statistics Service pest management practices survey to assess IPM adoption in California

Abstract Data from the pest management practices survey conducted annually by the National Agriculture Statistics Service were used to estimate the adoption of integrated pest management (IPM) in California. Surveys indicate 75% or greater use rates by acreage of 11 pest management practices in vegetable crop production in 2022 and 7 pest management practices in fruit and nut crop production in 2021. Agronomic crops have fewer pest management practices used on 75% or more of the acreage, with 4 in cotton in 2019, 6 in rice in 2021, 4 in wheat in 2022, and none in barley in 2019. Scouting for diseases, insects and mites, and weeds is the most widely used pest management practice in all the crops. Differences between use rates measured by acreage and use rates measured by farming operations suggest that large and small operations use different pest management practices. Trends indicate flat to increasing use of many pest management practices in general but decreasing use of some pest management practices in small grain crops. Changes in pest management practices and use rates are influenced by many factors, including University of California IPM efforts, changes in pesticide regulations, changes in crop production practices, and consumer pressures. The information from these surveys will support the development of Extension IPM outreach materials by the University of California Statewide IPM Program.

HYGIENIC REGULATIONS FOR THE SAFE APPLICATION OF COMBINED PESTICIDES IN THE CEREAL CROPS' CHEMICAL PROTECTION SYSTEM.

The aim: Hazard characterization and assessment of combined exposure to several pesticides when they simultaneously get to the human body with bakery products. Materials and methods: Methods of analytical analysis of the range of pesticide active substances, which are registered and used in modern systems of grain crop protection in Ukraine, were used in the study. Normative documents of national legislation on hygienic regulation of pesticides and methodological approaches to assessing the combined effects of pesticide mixtures in food products serve as materials for assessment. Results: It is established that the total risk of exposure to residual amounts of pesticides in bread products (wheat and rye bread) during its comparable getting into the body was 0.59 for children 2-6 years and 0.36 - for adults, with an allowable value of ≤ 1.0. The combined effect of pesticides per unit of children's body weight is higher, but also lies within acceptable limits. The largest contribution to the overall risk of combined exposure to triazoles is made by flutriafol (38.5-47.0%), which in the future may be the basis for substantiating measures to reduce such exposure and make appropriate management decisions. Conclusions: Safety of consumption of agricultural products is ensured by strict following hygienic regulations for the pesticide application (application rates, frequency of treatments, pre-harvest intervals), which makes it impossible to accumulate their residual amounts in food. Triazole pesticides, widely used in almost all crop protection systems, pose a potential risk of adverse health e!ects due to additive or synergistic effects.

National leverage points to reduce global pesticide pollution

There is an urgent need to reduce the environmental risk of pesticide pollution worldwide. We here explore national leverage points, using a novel dataset of 21.4 million georeferenced grid cells and a spatial regression discontinuity design. Our analysis lets us separate how much cross-country differences in the risk of pesticide pollution are caused by differences in countries’ agricultural systems and policies and how much is explained by other factors, such as environmental differences between the countries for example (e.g. pest pressures). We estimate that a third of the global cross-country differences in the pesticide pollution risk are caused by differences in countries’ agricultural systems and policies. The main explanations, and thus leverage points for policies, are differences in countries’ pesticide regulations, their share of organic farming, and type of crops that are grown. We find a trade-off between pesticide pollution risk and soil erosion only in the Americas and in Asia, but not elsewhere, and we do not find a trade-off between pesticide pollution risk and crop yield gaps.

Critical Review: Regulatory Differences Among Countries Expose the Permissiveness in the Use of Hazardous Pesticides in Brazil

This critical review warns of differences in pesticide registration and approval among major agricultural nations and classifications based solely on acute toxicity, which masks the risk of exposure to unapproved hazardous pesticides. It presents (a) the approval status of active pesticide ingredients (AI) in Brazil (BR) compared to other agricultural nations (e.g. European Union, USA and China); (b) the toxicological reclassification scenario of commercial pesticides in BR, and (c) the toxicological category of commercial pesticides in BR, with AI not approved for use in the three analyzed nations. A list of approved and not approved AI for use in Brazilian agriculture was compiled from the ANVISA website, and a comparison of the approval status among the agricultural countries was performed. Additionally, the number of commercial pesticides in classes/categories was compared before and after the toxicological reclassification from the ANVISA toxicological reclassification list. Among AI approved in BR, approximately 46.6% are “not approved” for use in at least one analysed nation. In addition, 43 pesticides (22,6%) were identified as approved in BR and not approved for use in two of the three nations. It is also noteworthy that nine pesticides (4,7%) are not approved for use in any of the three nations compared. Category 5, currently incorporated (product unlikely to cause acute harm), is the one that most absorbed products previously classified in Classes I (extremely toxic), II (highly toxic), and III (moderately toxic) (46.9%). Most formulations containing not approved active ingredients are classified in Categories 4 (slightly toxic) and 5 in BR. The negative effects that agrochemicals bring to the nation, such as on human health, or in wildlife, polluting water sources, and promoting a global problem by producing contaminated food, do not outweigh the economic benefits obtained by agribusiness.

Ecotoxicological and Chemical Approach to Assessing Environmental Effects from Pesticide Use in Organic and Conventional Rice Paddies

Despite laws and directives for the regulation and restriction of pesticides in farming, the large use of Plant-Protection Products (PPPs) in paddy fields is a relevant worldwide cause of environmental contamination. The aim of this work is to evaluate the environmental impact due to the use of PPPs by using an integrated approach based on chemical analyses and ecotoxicological hazard assessment, supported by statistical tools, in order to overcome the issues related to traditional tabular evaluation. Samples of soil and water of seven conventional and organic paddies located in Northern Italy were examined for two years. The results evidenced a direct relationship between the presence of Oxadiazon in water and bioassay responses as the main cause of the toxicity measured. This phenomenon affected both biological and conventional rice fields, due to the free circulation of water through irrigation canals. Therefore, the implementation of organic districts with water circulation isolated from conventional fields represents a simple and effective countermeasure to safeguard the agricultural practices of organic crops.

Key challenges and developments in wildlife ecological risk assessment: Problem formulation.

Problem formulation (PF) is a critical initial step in planning risk assessments for chemical exposures to wildlife, used either explicitly or implicitly in various jurisdictions to include registration of new pesticides, evaluation of new and existing chemicals released to the environment, and characterization of impact when chemical releases have occurred. Despite improvements in our understanding of the environment, ecology, and biological sciences, few risk assessments have used this information to enhance their value and predictive capabilities. In addition to advances in organism-level mechanisms and methods, there have been substantive developments that focus on population- and systems-level processes. Although most of the advances have been recognized as being state-of-the-science for two decades or more, there is scant evidence that they have been incorporated into wildlife risk assessment or risk assessment in general. In this article, we identify opportunities to consider elevating the relevance of wildlife risk assessments by focusing on elements of the PF stage of risk assessment, especially in the construction of conceptual models and selection of assessment endpoints that target population- and system-level endpoints. Doing so will remain consistent with four established steps of existing guidance: (1) establish clear protection goals early in the process; (2) consider how data collection using new methods will affect decisions, given all possibilities, and develop a decision plan a priori; (3) engage all relevant stakeholders in creating a robust, holistic conceptual model that incorporates plausible stressors that could affect the targets defined in the protection goals; and (4) embrace the need for iteration throughout the PF steps (recognizing that multiple passes may be required before agreeing on a feasible plan for the rest of the risk assessment). Integr Environ Assess Manag 2024;20:658-673. © 2022 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.

Prediction of acute poisoning in agricultural workers during using pesticides on berry and melon crops

acute pesticide poisoning is a global health problem. According to the WHO, poisoningby chemicals, including chemical plant protection products, is a leading non-communicable disease.Violation of the rules for working with pesticides leads to the occurrence of occupational diseasesamong workers. Therefore, compliance with pesticide regulations and the use of personal protective
 equipment is a very important preventive measure. The purpose of our work: to predict the occur-rence of acute toxic effects in workers who treat berry and melon crops with pesticides. Research
 materials and methods: to assess the probability of acute toxic effects among workers who deal withactive substances and preparations based on them. We calculated three indicators: the coefficient of
 possible inhalation poisoning (DSanPiN 8.8.1.002-98), the selectivity of pesticides by inhalation pes-ticides and the selectivity of pesticides under dermal exposure according to the method of Sergeeva
 S.G. Results: according to the “Hygienic classification of pesticides by degree of danger” DSanPiN8.8.1.002-98 all tested active substances belong to the 4th class of danger according to the coefficientof possible inhalation poisoning, which was less than 0,5. The coefficient of selectivity of the actionof pesticides during inhalation exposure to active substances was in the range of 7,41 – 1000,0.
 For cyprodinil, phenhexamid, azoxystrobin, pyraclostrobin, copper chloride, pendimethalin, S-me-tolachlor, glyphosate, and abamectin, it was less than 100, indicating their relatively low selectivity
 of action. Other studied active substances had a high selectivity of action, since this coefficient was
 more than 100. It was established that all studied drugs have sufficient selectivity of action when in-haled. The coefficient of selectivity for dermal exposure was more than 100 for all the studied active
 substances, except for S-metolachlor and glyphosate. Preparations Trinol, VG, Signum, VG, RidomilGold R 161 WG, VG, Stomp Aqua, SK, Dual Gold 960 EC, KE, Herbolex v.r. have low selectivityof action when entering through the skin, all other pesticides have sufficient selectivity of action. Theobtained data indicate that all the active substances under study are not dangerous (hazard class 4),according to DSanPiN 8.8.1.002-98. Therefore, when working with these substances you need tofollow hygienic regulations.

BCPC Congress 2022 – Delivers an Insight Into the Future of UK Agriculture

This year's BCPC Congress, returned to Harrogate on 7 and 8 November, and was attended by over 130 participants. Addressing the theme of 'Providing policy and regulatory support for multi-functional UK agriculture' the speakers – some presenting to the delegates on-line – delivered informative, thought-provoking and at times controversial presentations covering a range of issues. BCPC's General Manager, Julian Westaway said he was delighted that the Congress has again attracted such positive interest. The programme enabled them to deliver a great mix of authoritative speakers. Analysing the two days, there were key themes which were repeated throughout, namely agricultural policy, land-use and food security, future pesticide regulation in the UK, current pesticide regulatory issues, possible changes to pesticide management, current and future challenges to pesticide use.

Understanding the process of pesticide regulations, a cognitive and behavioral perspective

Understanding the process of pesticide regulations, a cognitive and behavioral perspective

Determination of Physical-chemical Parameters in Bee Products: A Preliminary Investigation from Africa’s Most Renewed Bee Village in Tanzania

Aim: The main objective of this study was to evaluate the determination of physical-chemical parameters in bee products: a preliminary investigation from Africa’s most renewed bee village in Tanzania; specifically, the study presents preliminary findings of an inquiry that examined pesticide contamination in bee products from Kijiji cha Nyuki located in Tanzania. The study measured the levels of physical-chemical parameters in honey products harvested from the selected bee apiaries.
 Material and Methods: A mixed methods approach was adopted for this study and collected data both primary and secondary data were collected using physical observation and survey, interviews, and questionnaires, purposive and random sampling techniques were used in this study to select a total of 104 participants who was taken as a sample from universal populations. Qualitative and quantitative data were analyzed using IBM Statistical Package for Social Sciences (SPSS) Computer Programme version 25, where the statistics aspect was determined from the results obtained from both questionnaires and laboratory experiments. A preliminary investigation from Africa’s most renewed bee village in Tanzania; Collected samples were analyzed at TBS & SGS laboratories.
 Results: The results show all studied areas met honey quality assurance guidelines stipulated by the ministry of natural resources and tourism suggesting moisture content in honey should not exceed 21%. pH test showed honey sample from Egypt apiaries had higher pH of 4.3 and honey from Kijiji cha Nyuki had a low pH of 3.54 implying honey from the studied areas falls within the pH applicable range. Test of Hydroxylmethly furfural mg/kg discovered an average of 13.65 mg/kg in honey samples from 4 studied areas out of the 5, with 107.13 mg/kg of HMF in honey samples from Egypt. Suggesting that honey samples from the 4 study areas with exception of samples from Egypt met the TZS 851:2006 standards and national’s guidelines of 40mg/kg Hydroxylmethly furfural. Finally, the Test of total reducing sugar as inverted sugar % m/m, from five samples as per Tanzania Bureau of Statistics (TBS) laboratory results found a maximum of 68.91 % m/m and 64.4 % m/m minimum. The amount of physical-mechanical contaminations that were identified in honey from 4 areas with the exemption of samples from Egypt apiaries poses no risk to consumers.
 Contribution to Policy Implication: This study recommends interventions among farmers and beekeepers on the safe use of pesticides, good hygienic handling, and the storage practices. It has contributed to the understanding of how the regulations outlining the use of insecticides is being implemented, and the current economic condition of studied farms. This calls on policymakers to rethink ways of engaging the beekeepers, and to have an ongoing discussion with beekeepers and concerned stakeholders about a model that could be used to enhance pesticides regulation in Tanzania.

Root colonization by arbuscular mycorrhizal fungi is reduced in tomato plants sprayed with fungicides

Arbuscular mycorrhizal fungi (AMF) form symbioses with many agricultural crops and can improve plant biomass and health. The performance of the AM symbiosis is context dependent, for example, usually the inoculation of the AMF Rhizophagus irregularis benefits plant biomass, but benefits can be suppressed by high soil fertility levels. Nevertheless, the importance of many other agricultural management practices on AMF, such as fungicides application, is poorly understood. Also, pesticide regulations usually neglect a comprehensive safety testing of fungicides on AMF and lawmakers require empirical support to improve such laws. The objective of this study was to evaluate the effects of spraying fungicides on tomato plants and the subsequent root colonization of plants grown in natural soil containing AMF and inoculated with R. irregularis. We detected that the inoculation of R. irregularis increased the total root colonization of the control plants that did not receive fungicides and that spraying the plants with the fungicides Signum ® and Topas ® reduced total root colonization. The effect on specific AM fungal structures was variable according to the product. Signum ® reduced the occurrence of arbuscules, while Topas ® reduced the occurrence of AM hyphae in the colonized roots. Cuprozin ® did not reduce total root colonization but reduced the occurrence of AM vesicles. Sampling time was also relevant. Effects were detected at 90 days, but not at 35 days. Our results show that fungicides safety should be evaluated for their effects on root colonization of crops in non-sterilized soils and at adequate sampling time.

Essential oils as green pesticides: An overview

Essential oils (EOs) obtained from different parts of plants consist of diverse chemical constituents. Most of the essential oils are rich in monoterpenes, sesquiterpenes and phenylpropenes. The diversity of chemical constituents imparts several biological activities such as insecticidal, repellent, attractant, antifeedant, oviposition deterrent, disruption in growth regulation, fungicidal and antiviral to these essential oils. Traditionally, EOs are being utilised for management of insect pests both in field crops and storage. Mostly these essential oils are found to affect insects by inhibiting several enzymes such as acetylcholine esterages, Glutathion S-transferages and also octopaminergic nervous system. They do not show toxicity against the mammals and fishes, due to absence of target site in these organisms. A few essential oils are exempted from pesticide registration and are being used as seasoning agents in food and beverage products. Moreover, these EOs can be a potential “green pesticide” against agricultural pests and support to the organic food production. The main purpose of this review is to emphasize on biological activities of EOs. This comprehensive and critical review will be helpful for chemists to develop more candidates based on these moieties and also for plant protectionists to identify promising EOs as per the need.

Розробка методичних підходів до нормування пестицидів у рослинних оліях

Abstract. Aim. Substantiation of priority indicators for establishing the maximum permissible levels (MPL) for active substances of pesticides in vegetable oils in accordance with modern international requirements and taking into account the peculiarities of their application in agriculture of Ukraine. Results. Based on the analysis of international and existing in Ukraine approaches to the development of MPL for pesticides in processed agricultural raw materials, criteria for assessing the need for research to determine and regulate the residual amounts of active substances of PPP in vegetable oils were suggested. The following main indicators that must be taken into account when normalizing pesticides in oils are substantiated: physicochemical and toxic properties of the active substance, the predicted level of its residual amounts in agricultural raw materials, the impact of technological processing on pesticide content. The principles of calculation of MPL for pesticides in oils of vegetable origin are given based on theoretical processing factors based on the FEDIOL concept, with the values of the partition coefficient between n-octanol and water and oil content in agricultural raw materials (seeds or grains of oilseeds) taken into account. The proposed concept is a basic one and provides for its further refinement and adjustment, in particular in accordance with the results of further studies on the regulation of plant protection products, which are currently relevant in the European Union. Conclusions. Methodological approaches to the establishment of MPLs for pesticides in vegetable oils need to be improved taking into account the international provisions and recommendations, set out in the article, in order to harmonize them and optimize the procedure for exporting plant products containing pesticide residues and introduction into the pesticide regulation system in Ukraine. Key Words: pesticides, residual quantities, norm setting, processed products, oilseeds.

Intermittent exposure to chlorpyrifos results in cardiac hypertrophy and oxidative stress in rats

Forbidden in some countries due to its proven toxicity to humans, chlorpyrifos (CPF) still stands as an organophosphate pesticide (OP) highly used worldwide. Cardiotoxicity assessment is an unmet need in pesticide regulation and should be deeply studied through different approaches to better inform and generate an appropriate regulatory response to OP use. In the present study, we used our 4-week intermittent OP exposure model in rats to address the CPF effects on cardiac morphology allied with cardiovascular functional and biomolecular evaluation. Rats were intermittently treated with CPF at doses of 7 mg/kg and 10 mg/kg or saline (i.p.) and assessed for cardiac morphology (cardiomyocyte diameter and collagen content), cardiopulmonary Bezold-Jarisch reflex (BJR) function, cardiac autonomic tone, left ventricle (LV) contractility, cardiac expression of NADPH oxidase (Nox2), catalase (CAT), superoxide dismutase 1 (SOD1), superoxide dismutase 2 (SOD2) and cardiac levels of advanced oxidation protein products (AOPP) and thiobarbituric acid reactive substances (TBARS). Plasma butyrylcholinesterase (BuChE) and brainstem acetylcholinesterase (AChE) were also measured. Intermittent exposure to CPF induced cardiac hypertrophy, increasing cardiomyocyte diameter and collagen content. An impairment of cardioinhibitory BJR responses and an increase in cardiac vagal tone were also observed in CPF-treated animals without changes in LV contractility. CPF exposure increased cardiac Nox-2, CAT, SOD1, and TBARS levels and inhibited plasma BuChE and brainstem AChE activities. Our data showed that intermittent exposure to CPF induces cardiac hypertrophy together with cardiovascular reflex impairment, imbalance of autonomic tone and oxidative stress, which may bring significant cardiovascular risk to individuals exposed to OP compounds seasonally.

Effect of pesticide ban on suicide trend – a 20-year study from a tertiary care center in Central Kerala from 2001 to 2020

Introduction: We assessed the effect of the pesticide regulations implemented in 2011 on suicide trend in Kerala state of India. Materials and methods: Data were collected from case records of suicide autopsies done in a single tertiary care hospital in Thrissur district of Kerala in 2001–2020. Linear trends in overall suicide rates were identified using joinpoint regression analysis. We used Poisson regression models to estimate the annual expected number of suicides in 2011–2020 and calculated the rate ratios between the observed number of suicide and that expected according to the linear pre-ban suicide trend (2005–2010). Results: There were a total of 14,593 suicide autopsies (2501 pesticide autopsies) in 2001-2020. Carbofuran was the commonest pesticide identified, followed by quinalphos, zinc phosphide, and chlorpyrifos. In 2011–2020, overall suicide rates were 22%–48% and pesticide suicide rates were 20%–55% lower than those expected according to pre-ban suicide trends (2005–2010), with the only exception of a 16% higher-than-expected pesticide suicide rate in 2011. There was no change in trend in hanging suicides. Conclusion: Lower-than-expected overall and pesticide suicide rates were found in Thrissur district after the 2011 bans of pesticides in Kerala, with no evidence of means replacement to hanging.

Framework for defining pesticide maximum residue levels in feed: applications to cattle and sheep.

Pesticide residues in animal feed can endanger animal health and compromise the safety of livestock products for human consumption. Even though policymakers such as the European Union and the World Health Organization have established maximum residue levels (MRLs) for pesticides in both human food and animal feed, there is no systematic management of pesticides in animal feed that considers the entire supply chain. In response, we propose a framework for defining consistent MRLs for pesticides in animal feed that assesses the impact of defined MRLs on upstream (e.g., MRLs in feed crops) and downstream (e.g., MRLs in livestock products) sectors of the livestock-product supply chain. The MRLs determined for the selected pesticides in the feed of cattle and sheep as case study animals indicate that lipophilic pesticides tend to have lower MRLs than hydrophilic pesticides, primarily due to the relatively high toxicity and biotransfer factors of lipophilic pesticides. In addition, we observe that, primarily for lipophilic pesticides, upstream and downstream regulations are not aligned in terms of defining MRLs in feed using current MRLs in crops with relevance to feed and foods of animal origin. Some of the current pesticide regulations in the livestock-product supply chain need to be re-evaluated to ensure that MRLs in the upstream sector (i.e., crops) do not result in unacceptable residues in the downstream sector (i.e., MRLs in livestock products affecting animal and human health). Finally, we provide recommendations for optimizing the derivation of MRLs in feed, including the evaluation of residue fate during feed and food manufacturing processes. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Acute toxicity of atrazine, alachlor, and chlorpyrifos mixtures to honey bees

The acute toxicity of chlorpyrifos and chlorpyrifos-oxon (organophosphorothioate insecticides) was examined alone and in combination with atrazine (triazine herbicide) and alachlor (chloroacetanilide herbicide) to honey bees (Apis mellifera). Atrazine and alachlor were observed to not be acutely toxic to bees at doses up to 10 and 4 μg per bee, respectively. However, atrazine significantly increased chlorpyrifos toxicity by 3-fold while reducing chlorpyrifos-oxon toxicity by 1.8-fold. These changes in toxicity are correlated with significant 1.3- and 1.2-fold inhibition of acetylcholinesterase (AChE) activity in bees exposed to chlorpyrifos and chlorpyrifos-oxon, respectively. Atrazine significantly increased cytochrome P450, general esterase, and glutathione S-transferase (GST) activities by 1.5-, 1.2-, and 1.2- fold respectively, in bees compared to untreated individuals. Alachlor increased chlorpyrifos toxicity by 2.5-fold but did not affect the toxicity of chlorpyrifos-oxon. Exposure to alachlor and chlorpyrifos did not affect AChE compared to chlorpyrifos alone. However, exposure to chlorpyrifos-oxon and alachlor significantly increased acetylcholinesterase (AChE) activity by 1.4-fold. GST activity, but not P450 or general esterases, was significantly increased in bees exposed to alachlor. These data provide evidence that triazine and chloroacetanilide herbicide exposure alters detoxification enzyme activity and, in turn, alters the sensitivity of bees to organophosphorothioate insecticides. Importantly, these data can be used to guide future studies aiming to test safety profiles for pollinators and expand regulatory framework required for pesticide registration.

Modern methodological approaches to the regulation of pesticides in soils

In the modern world, which is on the threshold of eight billion people, the issue of food security takes one of the leading places. Due to the limited amount of agricultural land, it is necessary to increase the yield of the fields, which is almost impossible without the use of chemical plant protection products. In turn, the use of pesticides carries huge risks to public health. Application of pesticides in the cultivation of agricultural lands can lead to their transfer into the human body in different ways. Pesticides can be transported with subsurface and lateral runoff into water reservoirs, from where they can reach the centralized water supply or be withdrawn from water sources by residents of settlements close to agricultural fields. Pesticide active volatile ingredients can evaporate from the soil surface and move over long distances. In addition, translocation of pesticides from soil to plants is a source of public health risk, which may result in further transfer of active substances in concentrations exceeding maximum residue levels (MRL) into human foodstuffs. In the same time, persistent pesticides can accumulate in the soil and subsequently lead to disruption of soil functioning. Therefore, hygienic regulation of pesticides is the most important issue in ensuring public safety. In addition to MAC values, it is proposed to use values based on the MAC: maximum allowable application level (MAEL) and safe residual quantity (SRQ). These values would allow to increase the level of protection of the population from potential harms of pesticides used in agricultural practices for specific soil and climate zones.

Estimating rates of pesticide usage from trends in herbicide, insecticide, and fungicide product registrations

Insecticides, herbicides, and fungicides are ubiquitously applied in agricultural production systems to increase yields by managing insect pests, weeds, and diseases. While valuable, these chemicals can also have unwanted off-target effects on human health, biodiversity, and resistance evolution. Pesticide usage data can help to estimate and mitigate these impacts, but many countries lack spatial data on chemical usage trends. In contrast to pesticide usage, data on pesticide registration are more widely available and often organised into structured databases in accordance with governmental regulatory requirements. Here, we explored the extent to which pesticide registration databases can infer patterns of usage across agricultural pesticides, based on United States (US) and Australian data. Our predictive models explained 56% and 38% of the variation in pesticide usage across the US and Australia, respectively, with pesticide registrations explaining 58% and 23% of this variation and the remainder explained by land use patterns. Our results show that pesticide registrations can help to infer usage patterns across different chemical groups, active ingredients, and agricultural regions. Increasing numbers of registered products, pests, and products for a given active ingredient were associated with increased usage. However, there remains unexplained variation in pesticide usage patterns between active ingredient groups, highlighting the importance of additional explanatory factors. The value of chemical registration databases could be further enhanced through registration against taxonomically-identified pest species, rather than relying on common names or broadly defined groups. The associations detected in our work could be used to improve estimates of pesticide usage in countries lacking reliable data.