Pesticide Active Ingredients Research Articles

Pesticides and Soil Invertebrates: A Hazard Assessment

Agricultural pesticide use and its associated environmental harms is widespread throughout much of the world. Efforts to mitigate this harm have largely been focused on reducing pesticide contamination of the water and air, as runoff and pesticide drift are the most significant sources of offsite pesticide movement. Yet pesticide contamination of the soil can also result in environmental harm. Pesticides are often applied directly to soil as drenches and granules and increasingly in the form of seed coatings, making it important to understand how pesticides impact soil ecosystems. Soils contain an abundance of biologically diverse organisms that perform many important functions such as nutrient cycling, soil structure maintenance, carbon transformation, and the regulation of pests and diseases. Many terrestrial invertebrates have declined in recent decades. Habitat loss and agrichemical pollution due to agricultural intensification have been identified as major driving factors. Here, we review nearly 400 studies on the effects of pesticides on non-target invertebrates that have egg, larval, or immature development in the soil. This review encompasses 275 unique species, taxa or combined taxa of soil organisms and 284 different pesticide active ingredients or unique mixtures of active ingredients. We identified and extracted relevant data in relation to the following endpoints: mortality, abundance, biomass, behavior, reproduction, biochemical biomarkers, growth, richness and diversity, and structural changes. This resulted in an analysis of over 2,800 separate “tested parameters,” measured as a change in a specific endpoint following exposure of a specific organism to a specific pesticide. We found that 70.5% of tested parameters showed negative effects, whereas 1.4% and 28.1% of tested parameters showed positive or no significant effects from pesticide exposure, respectively. In addition, we discuss general effect trends among pesticide classes, taxa, and endpoints, as well as data gaps. Our review indicates that pesticides of all types pose a clear hazard to soil invertebrates. Negative effects are evident in both lab and field studies, across all studied pesticide classes, and in a wide variety of soil organisms and endpoints. The prevalence of negative effects in our results underscores the need for soil organisms to be represented in any risk analysis of a pesticide that has the potential to contaminate soil, and for any significant risk to be mitigated in a way that will specifically reduce harm to soil organisms and to the many important ecosystem services they provide.

Tank-mixing adjuvants enhanced the efficacy of fludioxonil on cucumber anthracnose by ameliorating the penetration ability of active ingredients on target interface

In this study, pot and field experiments showed that S903, Hasten and Gemini-31511 can significantly enhanced the control efficacy of fludioxonil on cucumber anthracnose. Then by studying the deposition and penetration interaction between active ingredients and cucumber leaves to revealed how the adjuvants influence the interaction process between pesticide active ingredients and target plants to improve the control efficacy. By analysis the effect of fludioxonil deposition to synergism of adjuvants, indicated that fludioxonil active ingredient deposition caused by adjuvants was not the main factor for the adjuvants synergistic effect. Fludioxonil + S903 yielded the lowest surface tension and contact angle, which also implying the best wetting ability. The mean diameters in Hasten + fludioxonil group were much smaller than those in only fludioxonil group (5.39 μm–90 g a.i. ha−1, 5.50 μm–180 g a.i. ha−1), the average particle size only had 3.45 μm (90 g a.i. ha−1) and 3.94 μm (180 g a.i. ha−1). And the result of spray droplets was consistent with the particles of fludioxonil crystals observed on glass slides and cucumber leaves. Therefore, S903 improved the penetrability of fludioxonil in the target plants by improving the wetting and dispersion of active ingredients on the target interface. Meantime, Hasten improved the penetrability of fludioxonil in the target plants by decreasing the particle size of active ingredients.

A world view of pesticides

Pesticide pollution is a widespread issue. A global risk assessment of 92 active pesticide ingredients suggests 2.5 billion hectares of agricultural land are at risk of pollution by more than one active ingredient.

Exposure to multiple pesticides and neurobehavioral outcomes among smallholder farmers in Uganda

BackgroundMultiple epidemiological studies have shown that exposure to single pesticide active ingredients or chemical groups is associated with adverse neurobehavioral outcomes in farmers. In agriculture, exposure to multiple pesticide active ingredients is the rule, rather than exception. Therefore, occupational studies on neurobehavioral effects of pesticides should account for potential co-exposure confounding. MethodsWe conducted a cross-sectional study of 288 Ugandan smallholder farmers between September and December 2017. We collected data on self-reported use of pesticide products during the 12 months prior to survey and estimated yearly exposure-intensity scores for 14 pesticide active ingredients using a semi-quantitative exposure algorithm. We administered 11 neurobehavioral tests to assess five neurobehavioral domains. We implemented a Bayesian Model-Averaging (BMA) approach to examine the association between exposure to multiple pesticides and neurobehavioral outcomes, while accounting for multiple testing. We applied two levels of inference to determine (1) which neurobehavioral outcomes were associated with overall pesticide exposure (marginal inclusion probability (MIP) for covariate-only models <0.5) and (2) which specific pesticide active ingredients were associated with these outcomes (MIP for models where active ingredient was included >0.5). ResultsSeventy-two percent of farmers reported use of pesticide products that contained at least one of 14 active ingredients, while the applicators used in median three different active ingredients (interquartile range (IQR) 4) in the 12 months prior to the study. The most widely used active ingredients were glyphosate (79%), cypermethrin (60%), and mancozeb (55%). We found that overall pesticide exposure was associated with impaired visual memory (Benton Visual Retention Test (BVRT)), language (semantic verbal fluency test), perceptual-motor function (Finger tapping test), and complex attention problems (Trail making A test and digit symbol test). However, when we looked at the associations for individual active ingredients, we only observed a positive association between glyphosate exposure and impaired visual memory (-0.103 [95% Bayesian Credible Interval (BCI)] [-0.24, 0] units in BVRT scores per interquartile range (IQR) increase in annual exposure to glyphosate, relative to a median [IQR] of 6 [3] units in BVRT across the entire study population). ConclusionsWe found that overall pesticide exposure was associated with several neurobehavioral outcome variables. However, when we examined individual pesticide active ingredients, we observed predominantly null associations, except for a positive association between glyphosate exposure and impaired visual memory. Additional epidemiologic studies are needed to evaluate glyphosate’s neurotoxicity, while accounting for co-pollutant confounding.

A comprehensive systematic review of photocatalytic degradation of pesticides using nano TiO2.

This study has systematically reviewed all of the research articles about the photocatalytic degradation of pesticides using titanium dioxide (TiO2) nanoparticles (NPs) and ultraviolet (UV) irradiation. Online databases were searched for peer-reviewed research articles and conference proceedings published during 2009-2019, and ultimately 112 eligible articles were included in the review. Fifty-three active ingredients of pesticides and one mixture had been investigated, most of them were organophosphorus (22%), followed by triazine derivatives (11%), chloropyridines (9%), and organochlorines (9%). Sixteen types of TiO2 with an average photodegradation efficiency of 71% were determined. Based on the type of pesticide and experimental conditions such as irradiation time, the complete photodegradation had been observed. The removal of each group of pesticides has been sufficiently discussed in the article. Effect of experimental conditions on photocatalytic activity has been investigated using linear and polynomial regressions. The strategies to reduce the required energy for this process, doping TiO2 with metal and non-metal agents, innovative reactor designs, etc., were also discussed. In conclusion, TiO2 NPs have been successful for degradation of pesticides. Future direction for research incorporates developing and application of heterogeneous doped and immobilized titania having optimized characteristics such as surface area, reactive centers, recombination rate, and phase, and capable to photo-degrade low levels of pesticides residues under solar light in an efficient full-scale size.

Модифікований метод екотоксів для інтегрального оцінювання потенційної екологічної небезпеки сучасних пестицидних препаратів

The problem of pesticide pollution of all layers of the biosphere remains acute not only in Ukraine but also around the world. In this case, pesticides and their preparations (PP) are "toxic substances, their compounds or mixtures of substances of chemical or biological origin, designed to destroy, regulate and stop the development of harmful organisms that affect plants, animals, humans and damage property, as well as rodents, weeds, trees, shrubs, clogging fish species "[1]. That is, these are chemical compounds that are used to protect plants and agricultural products, as well as to control vectors of dangerous diseases. However, all of them, or the vast majority of them, are toxic and pose a significant danger to humans and the environment. Therefore, it is necessary to develop such a simplified and universal, but at the same time, effective method of gradation according to the degree of their toxicity. The essence of the modified method of ecotoxics is that such a method of calculation should include the main toxicological parameters of the chemical detected in the environment and indicators of spontaneous cleavage (decomposition) of the compound in a particular environment. Thousands of brands of pesticides from many manufacturers are used worldwide. New more effective pesticide mixtures are constantly being developed and registered in Ukraine. However, the active ingredients of pesticides are relatively few. The dangers to the environment and human health from the use of pesticides are well known, but the dependence of pesticide residual activity on the environment is poorly understood. Relevance: when using pesticides, the main hazard parameter is LD50 in rats or other warm-blooded animals. However, toxicity measures such as exposure time or pesticide application rates are not considered. Quite often very toxic pesticides decompose quite quickly in the soil and on the contrary low-toxic pesticides poison the environment for many months or even years. Although there are a large number of patented brands of pesticides, their chemical composition does not differ significantly. Pesticides of the same composition are patented under different names to generate profits without paying interest to the patent owner and, accordingly, to generate additional profits. As a rule, the active substance in pesticides from different manufacturers may be similar. The ratio of the active substance to the solvent, the amount and composition of solvents, the mixture in a certain ratio of several active substances of pesticides are excellent. Table 5.9 lists the trade names of pesticides used in Ukraine and supplied by international chemical giants.

Regulatory status of pesticide residues in cannabis: Implications to medical use in neurological diseases

Medical cannabis represents a potential route of pesticide exposure to susceptible populations. We compared the qualifying conditions for medical use and pesticide testing requirements of cannabis in 33 states and Washington, D.C. Movement disorders were the most common neurological category of qualifying conditions, including epilepsy, certain symptoms of multiple sclerosis, Parkinson’s Disease, and any cause of symptoms leading to seizures or spasticity. Different approaches of pesticide regulation were implemented in cannabis and cannabis-derived products. Six states imposed the strictest U.S. EPA tolerances (i.e. maximum residue levels) for food commodities on up to 400 pesticidal active ingredients in cannabis, while pesticide testing was optional in three states. Dimethomorph showed the largest variation in action levels, ranging from 0.1 to 60 ppm in 5 states. We evaluated the potential connections between insecticides, cannabinoids, and seizure using the Comparative Toxicogenomics Database. Twenty-two insecticides, two cannabinoids, and 63 genes were associated with 674 computationally generated chemical-gene-phenotype-disease (CGPD) tetramer constructs. Notable functional clusters included oxidation-reduction process (183 CGPD-tetramers), synaptic signaling pathways (151), and neuropeptide hormone activity (46). Cholinergic, dopaminergic, and retrograde endocannabinoid signaling pathways were linked to 10 genetic variants of epilepsy patients. Further research is needed to assess human health risk of cannabinoids and pesticides in support of a national standard for cannabis pesticide regulations.

Pesticides and Pesticide Degradates in Groundwater Used for Public Supply across the United States: Occurrence and Human-Health Context.

This is the first assessment of groundwater from public-supply wells across the United States to analyze for >100 pesticide degradates and to provide human-health context for degradates without benchmarks. Samples from 1204 wells in aquifers representing 70% of the volume pumped for drinking supply were analyzed for 109 pesticides (active ingredients) and 116 degradates. Among the 41% of wells where pesticide compounds were detected, nearly two-thirds contained compound mixtures and three-quarters contained degradates. Atrazine, hexazinone, prometon, tebuthiuron, four atrazine degradates, and one metolachlor degradate were each detected in >5% of wells. Detection frequencies were largest for aquifers with more shallow, unconfined wells producing modern-age groundwater. To screen for potential human-health concerns, benchmark quotients (BQs) were calculated by dividing concentrations by the human-health benchmark, when available. For degradates without benchmarks, estimated values (estimated benchmark quotients (BQE)) were first calculated by assuming equimolar toxicity to the most toxic parent; final analysis excluded degradates with likely overestimated toxicity. Six pesticide compounds and 1.6% of wells had concentrations approaching levels of potential concern (individual or summed BQ or BQE values >0.1), and none exceeded these levels (values >1). Therefore, although pesticide compounds occurred frequently, concentrations were low, even accounting for mixtures and degradates without benchmarks.

Polyphenol-Based Microencapsulated Extracts as Novel Green Insecticides for Sustainable Management of Polyphagous Brown Marmorated Stink Bug (Halyomorpha halys Stål, 1855)

The brown marmorated stink bug (Halyomorpha halys Stål, 1855) is an invasive polyphagous species that threatens fruit growing both in the United States and Europe. Many pesticide active ingredients have been studied in H. halys management, but for sustainable fruit growing, which implies the reduction of chemical harm to the environment, new safe insecticides should be implemented into the practice. For this purpose, novel green insecticide based on natural polyphenols of species Stevia rebaudiana (Bertoni) Bertoni and Aronia melanocarpa (Michx.) Elliott 1821 was developed. Stevia leaves (SLE) and Aronia pomace (APE) aqueous extracts were prepared using the ultrasound-assisted extraction method. Optimal extraction conditions for bioactive compounds (total polyphenols, flavonoids, anthocyanins, and flavan-3-ols, respectively) and antioxidant activity were determined using response surface methodology. Bioactive compounds rich SLE and APE were encapsulated in calcium alginate microparticles by the ionic gelation method. Physicochemical characteristics (morphology, size, encapsulation efficiency, loading capacity, and swelling) of microparticles showed very good properties with especially high encapsulation efficiency. Fitting to simple Korsmeyer–Peppa’s empirical model revealed that the underlying release mechanism of polyphenols is Fickian diffusion. SLE loaded microparticles showed very good pesticidal efficiency against Halyomorpha halys, especially on younger larval stages after both contact and digestive treatment. Microparticles loaded with APE did not achieve satisfactory digestive efficiency, but a certain toxic impact has been observed at contact application on all H. halys growth stages. Microparticles loaded with SLS exhibited prolonged insecticidal action against H. halys and could be a potential candidate as a green insecticide whose application could increase fruit growing safety.

Effect of agrochemicals on biomass production and quality parameters of tobacco plants

Modern agriculture involves the use of synthetic compounds (agrochemicals) in order to maximize crop yields. However, inappropriate fertilization and/or the use of pesticides can have adverse effects on crop productivity and quality. In this context, a study has been carried out to ascertain the effect of increasing dosages of a chemical fertilizer (Greenhouse Special) and some widely used pesticides on tobacco plants. To this purpose biomass, chlorophyll contents and the concentration of NO3 − and NH4 + were determined. Results showed that NO3 − and NH4 + significantly accumulated in tobacco plants following the application of the two the highest fertilizer dosages. Furthermore, some pesticides altered NO3 − and NH4 + concentration in leaves. Finally, in order to estimate the effect of these compounds on nitrogen acquisition and metabolism, Nitrogen Use Efficiency was evaluated. Data of NUE evidenced that the optimal dosage of fertilizer was 0.250 g/plant. Moreover, it was found that the active ingredients of pesticides affected NUE in the species studied.

Cascading effects of insecticides and road salt on wetland communities.

Novel stressors introduced by human activities increasingly threaten freshwater ecosystems. The annual application of more than 2.3 billion kg of pesticide active ingredient and 22 billion kg of road salt has led to the contamination of temperate waterways. While pesticides and road salt are known to cause direct and indirect effects in aquatic communities, their possible interactive effects remain widely unknown. Using outdoor mesocosms, we created wetland communities consisting of zooplankton, phytoplankton, periphyton, and leopard frog (Rana pipiens) tadpoles. We evaluated the toxic effects of six broad-spectrum insecticides from three families (neonicotinoids: thiamethoxam, imidacloprid; organophosphates: chlorpyrifos, malathion; pyrethroids: cypermethrin, permethrin), as well as the potentially interactive effects of four of these insecticides with three concentrations of road salt (NaCl; 44, 160, 1600 Cl- mg/L). Organophosphate exposure decreased zooplankton abundance, elevated phytoplankton biomass, and reduced tadpole mass whereas exposure to neonicotinoids and pyrethroids decreased zooplankton abundance but had no significant effect on phytoplankton abundance or tadpole mass. While organophosphates decreased zooplankton abundance at all salt concentrations, effects on phytoplankton abundance and tadpole mass were dependent upon salt concentration. In contrast, while pyrethroids had no effects in the absence of salt, they decreased zooplankton and phytoplankton density under increased salt concentrations. Our results highlight the importance of multiple-stressor research under natural conditions. As human activities continue to imperil freshwater systems, it is vital to move beyond single-stressor experiments that exclude potentially interactive effects of chemical contaminants.

Assessment of Ecological Risk and Environmental Behavior of Pesticides in Environmental Compartments of the Formoso River in Tocantins, Brazil.

Anthropogenic interference the ecosystem unavoidably changes the physical and biological environment. The biodiversity of the Amazon region has been threatened by increased agricultural production and pesticide use. Considering that monitoring pesticides in environments close to their application is one of the ways to preserve the ecosystem, this study investigated the levels of pesticide residues in different environmental compartments (soil, sediment, and water samples). Thirty-one active ingredients of pesticides of different classes were analyzed by UHPLC-MS/MS. For this purpose, we performed quarterly collections in dry and rainy seasons in the region, which helped to evaluate the impact of pesticides on the biodiversity of the study site. Sampling points were the river banks in the area of an agricultural project in Formoso do Araguaia city, Tocantins State. After analysis, we detected the following substances in the water matrix: clomazone, fluazifop-p-butyl, flutolanil, metsulfuron-methyl, propanil, and imidacloprid. Nevertheless, we did not detect any active ingredient in sediment and soil matrices. The active ingredient clomazone was present in all points in the trials, with concentrations reaching up to 0.538μgL-1. These substances have potential for groundwater contamination. Even at low concentrations in the aquatic ecosystem, these substances can damage human populations and wildlife species, given their toxicological classification. Thus, the study showed an environmental risk of bioaccumulation and/or biomagnification in the region, which may affect environmental biodiversity as well as human health.

Changes in the aquatic ecotoxicological effects of Triton X-100 after UV photodegradation.

Various spray adjuvants including surfactants are widely used in agricultural pesticide formulations, and some of them may remain in soils and waters and impose more adverse effects than active pesticide ingredients on organisms. However, previous studies are more focused on the active pesticide ingredients than the adjuvants. Thus, this study investigates the changes in toxic effects of surfactants during photodegradation, which is one way of naturally degrading contaminants in natural waters. Triton X-100, a water-soluble non-ionic surfactant, was degraded using different types of UV radiation (UVA, UVB, and UVC), and the changes in the toxic effects were determined using bioluminescent bacteria and water flea. The Triton X-100 removals were negligible with UVA within 24 h, while its removal was 81% with UVB and almost complete with UVC. The NMR spectra indicated possible molecule rearrangement after photolysis. On the other hand, the toxic effects based on the mortality of Daphnia magna and the bioluminescence of Aliivibrio fischeri increased (i.e., lower EC50 values) after photodegradation, suggesting the generation of photoproducts that are likely to have higher toxic effects or higher bioavailability. Furthermore, the sensitivities of D. magna and A. fischeri for Triton X-100 and the photodegraded Triton X-100 were different. This study suggests that the changes in the chemical composition of the Triton X-100 containing water with photodegradation can lead to changes in the relative toxic effects on different aquatic organisms. Therefore, not only the management of parent compound (i.e., Triton X-100) but also the photoproducts generated from the parent compound need to be considered when managing water environment subject to photodegradation.

Epigenome-wide Association Study of DNA Methylation and Specific Pesticide Use Among U.S. Farmers

Background: Pesticide exposure is associated with certain cancers and neurologic diseases, but the underlying mechanisms are not fully understood. DNA methylation, an epigenetic modification, may play a role. DNA methylation patterns likely differ by specific pesticide, but no epigenome-wide association studies have evaluated methylation patterns across different pesticides. We conducted epigenome-wide analyses of DNA methylation in relation to several pesticides used among U.S. farmers.Methods: The Agricultural Lung Health Study (ALHS) is a case-control study of asthma, nested within the Agricultural Health Study (AHS). For 1,170 ALHS male farmers, blood DNA methylation was measured with Illumina’s MethylationEPIC array. Participants self-reported pesticide use in the AHS (past use) and ALHS (current use, defined as past 12 months). Pesticides were grouped by chemical class and active ingredients. Using robust linear regression, we analyzed 13 chemical classes and 16 active ingredients with 30+ exposed men. Analyses were adjusted for age, smoking status, packyears, state, asthma status, and estimated cell type proportions.Results: Participants who reported past and current use of pesticide class or active ingredient were compared to those who never reported use. Using family-wise error rate (p&lt;9×10-8) or false discovery rate (p&lt;0.05), we identified differentially methylated C-phosphate-G (CpG) sites for 10 chemical classes and 9 active ingredients. Most differentially methylated CpG sites were unique to each active ingredient. For 5 of the 9 active ingredients, lifetime days of use was available and there was evidence of a dose-response at most differentially methylated CpG sites. Significant CpG sites were enriched for transcription factor motifs. We plan to correlate significant CpG sites with gene expression in external data.Conclusions: We observed differential methylation associated with several chemical classes and active ingredients. These differential methylation patterns could be biomarkers of long-term exposure and may provide additional biological insight into health effects of pesticide exposure.

Occupational Pesticide Use and Risk of Non-Hodgkin Lymphoma

Background. Evidence on the human health effects of pesticides is needed to inform risk assessment.Methods. We conducted a large study of the relationship between occupational pesticide use and risk of non-Hodgkin lymphoma (NHL, including chronic lymphocytic leukemia and multiple myeloma) by pooling data from nine case-control studies participating in the InterLymph Consortium, including 7909 cases and 8644 controls from North America, the European Union, and Australia. Pesticide use was coded using a combination of self-report and expert assessment, for pesticide active ingredients (e.g., DDT, diazinon, 2,4-D, glyphosate) and chemical groups (e.g., organophosphate (OP) insecticides, phenoxy herbicides). We estimated the association between each exposure and risk of NHL using logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CI), with adjustment for age, gender, race, socioeconomic status, study location, and any pesticide use – for NHL, and separately for NHL subtypes.Results. OP insecticides were associated with increased risk of NHL. In particular, there was 43% higher risk associated with diazinon use (vs. never, 95% CI: 1.02, 2.00) and the association was stronger with longer duration (e.g., highest tertile duration vs. never, OR=2.40, 95% CI: 1.20, 4.78). We found no association between all NHL and pyrethroid insecticides or DDT. The phenoxy herbicide, 2,4-D, was associated with increased risk of NHL, and risk was most elevated for use within 20 years of diagnosis (i.e., unlagged) (e.g., ever vs. never: unlagged, OR=1.56, 95% CI: 1.06, 2.28; lagged, OR=1.23, 95% CI: 0.96, 1.56). Glyphosate use was not associated with risk of all NHL, but there were statistically significant risk increases for some NHL subtypes, specifically follicular lymphoma and NOS/unknown pathology.Conclusions. Our consortium-based pooled study produced evidence on potential carcinogenicity of certain pesticides. These findings are important because farming occupation and pesticides are among few leads for environmental causes of NHL.

Novos agrotóxicos e o padrão de potabilidade da água: dinâmica ambiental e riscos à saúde

Pesticides are widely used in Brazil. Once in the environment, they can contaminate the air, the water and the soil, and they may cause harm to human health. With the recurrent approval of many registers of pesticides in Brazil, the aim of this paper is to evaluate the environmental dynamic and the toxicity of the active ingredients of pesticides that had their records approved from January 2018 to December 2019, along with a suggestion of possible guideline values for the equivalent concentration in Brazilian drinking water. Of the 15 compounds that were approved in the period, were selected only the chemical compounds (Dinotefuran, Florpyrauxifen-benzyl, Fluopyram, Sulfoxaflor), excipient ones and microbiological agents were excluded. Dinotefuran and Fluopyram stood out for presenting high toxicity and environmental persistence, which may indicate the possibility of exposure of human beings to high levels of these pesticides by water consumption. Sulfoxaflor, on the other hand, despite having unfavorable environmental dynamics to the contamination of water sources, requires monitoring of its occurrence in water supply systems, due to its high toxicity. Finally, Florpyrauxifen-benzyl has not shown evident risk that justifies its monitoring in water sources.

Contaminação dos recursos hídricos por agrotóxicos na região central do Rio Grande do Sul, Brasil

O aumento na utilização de agrotóxicos na agricultura pode trazer graves consequências ao meio ambiente e à saúde da população, que consumir alimentos e água com resíduos de tais substâncias. Desta forma, o presente estudo buscou avaliar a presença e a concentração de agrotóxicos na água para consumo humano e, com isso, compreender os riscos à saúde que a população do município de Cachoeira do Sul está submetida. A metodologia consistiu na coleta e análise de amostras de água, em cinco épocas do ano, entre agosto de 2017 a março de 2018, sendo realizadas duas coletas de água tratada (na estação de tratamento e numa instituição de ensino) e uma de água do rio Jacuí, que abastece a cidade, sendo um total de 15 amostras. As amostras foram submetidas a análise por extração em fase sólida e cromatografia gasosa e líquida acoplada a espectrometria de massas. Os resultados mostraram a presença de resíduos de agrotóxicos em todas as amostras, com período crítico para contaminação entre fevereiro e março. No total, foram identificados 18 princípios ativos de agrotóxicos nas amostras de água, sendo o inseticida imidacloprido o de maior incidência e concentração, seguido pelos herbicidas clomazone e quincloraque. Os poluentes analisados persistiram mesmo após o tratamento da água, expondo a população aos riscos potenciais pela ingestão diária destes componentes. Medidas que promovam a remoção destes compostos na água, bem como alternativas ao modelo agrícola convencional precisam ser desenvolvidas e ampliadas, para promover a redução ou eliminação do uso dos agrotóxicos e proteção da saúde e meio ambiente.

Pesticide risk indicator for terrestrial adult stages of aquatic insects

Many taxonomic groups of freshwater insects have a reproductive terrestrial life stage, and some are highly sensitive to insecticides. In agricultural landscapes, it is likely that streams and rivers often run along agricultural fields treated with pesticides, but the risk to insects with a reproductive terrestrial life stage due to pesticide exposure is not well-covered by existing risk indicators. Different aquatic insect species may have different strategies for feeding and mating and, thus, different spatial and temporal distribution of the terrestrial abundance. This influences the fraction of individuals that can suffer from pesticide exposure, and thus the risk indicator in this paper includes spatial and temporal distributions of both insect abundance and air born pesticide deposition, in this case multiplied together and weighted with toxicity. The indicator is denoted Adult Stage Risk Indicator, ASRIi,j, and can be calculated for every combination of insect taxon i, and pesticide active ingredient j. An Excel/VBA based model is available as Supplementary material. However, setting up the indicator using another platform is simple, and for any application please refer to this paper.

Safety of imported agricultural products: pesticide residues

Introduction. From the evaluation of the positions of residual quantities of pesticides, the hygienic safety assessment of imported food products is most relevant under the current agreement on a free trade zone between the EAEU and the Socialist Republic of Vietnam, as well as in connection with a large list of chemical plant protection products used during the vegetation of crops. The purpose of the study. Rating the level of residual quantities of pesticides in samples of selected food products produced in Vietnam is the purpose of the study. Research objectives. To quantify 42 active ingredients of pesticides (and their metabolites) in samples of rice grain, dragon fruit (pitahaya), avocado, mango and banana (fresh and dried) are the research objectives. Material and methods. Multicomponent and individual methods based on LC and GC with MS-detection and FLD were used to identify active ingredients of pesticides. The sample preparation procedure with QuEChERS technology was used for the multi residues determination of the 40 compounds. The determination of avermectins (abamectin and emamectin benzoate) was carried out after the conversion of substances into fluorogenic derivatives. Results. Residual amounts of tebuconazole (rice - 0.53 ppm, mangoes - 0.26 ppm, avocado - 0.15 ppm), fludioxonil (rice - 0.017 ppm), imidacloprid (dried mangoes - 0.01 ppm), carbendazim (dried mangoes - 0.011 ppm) were identified in single samples No residual avermectins have been identified. The content of substances in the analyzed samples of dragon fruit (pitahaya) did not exceed 0.01 ppm. Discussion. The results obtained in the work are compared with the data of the annual pan-European and national monitoring, information on which is publicly available (2017), including imported goods, according to which rice and dragon fruits as objects of monitoring are given increased attention. Conclusions. The safety of certain types of food products imported from Vietnam is shown by the content of residual quantities of pesticides.

Prenatal exposure to pesticides and risk for holoprosencephaly: a case-control study

BackgroundPesticide exposure during susceptible windows and at certain doses are linked to numerous birth defects. Early experimental evidence suggests an association between active ingredients in pesticides and holoprosencephaly (HPE), the most common malformation of the forebrain in humans (1 in 250 embryos). No human studies to date have examined the association. This study investigated pesticides during multiple windows of exposure and fetal risk for HPE. It is hypothesized that pre-conception and early pregnancy, the time of brain development in utero, are the most critical windows of exposure.MethodsA questionnaire was developed for this retrospective case-control study to estimate household, occupational, and environmental pesticide exposures. Four windows of exposure were considered: preconception, early, mid and late pregnancy. Cases were identified through the National Human Genome Research Institute’s ongoing clinical studies of HPE. Similarly, controls were identified as children with Williams-Beuren syndrome, a genetic syndrome also characterized by congenital malformations, but etiologically unrelated to HPE. We assessed for differences in odds of exposures to pesticides between cases and controls.ResultsFindings from 91 cases and 56 controls showed an increased risk for HPE with reports of maternal exposure during pregnancy to select pesticides including personal insect repellants (adjusted odds ratio (aOR) 2.89, confidence interval (CI): 0.96–9.50) and insecticides and acaricides for pets (aOR 3.84, CI:1.04–16.32). Exposure to household pest control products during the preconception period or during pregnancy was associated with increased risk for HPE (aOR 2.60, OR: 0.84–8.68). No associations were found for occupational exposures to pesticides during pregnancy (aOR: 1.15, CI: 0.11–11.42), although exposure rates were low. Higher likelihood for HPE was also observed with residency next to an agricultural field (aOR 3.24, CI: 0.94–12.31).ConclusionsObservational findings are consistent with experimental evidence and suggest that exposure to personal, household, and agricultural pesticides during pregnancy may increase risk for HPE. Further investigations of gene by environment interactions are warranted.