Biomarkers of occupational exposure to pesticides: Systematic review of insecticides

Optimization, validation, and application of a liquid chromatography-tandem mass spectrometry method for the determination of 47 banned drug and related chemical residues in livestock urine using graphitized carboxyl multi-walled carbon nanotubes-based QuEChERS extraction

The establishment of an efficient method for the analysis of drug residues in animal urine facilitates the real-time monitoring of drugs used in the production of animal-derived food. A modified QuEChERS extraction-liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was established for the determination of 47 banned drug and related chemical residues in livestock urine. The sample was extracted with acetonitrile by converting the acid-base environment. The sample cleanup effects of seven solid phase extraction cartridges and two EMR-Lipid products were compared, and three materials, including graphitized carboxyl multi-walled carbon nanotubes (MWCNTs), PSA, and C18, were selected as QuEChERS adsorbents from 24 materials. All analytes showed good linearity, with correlation coefficients (R2) greater than 0.9936. Low limits of quantification could be obtained, ranging from 0.2 to 5.5 ng/mL. The average recoveries at low, medium, and high spiked levels were in the range of 70.8-114.9 %, with intra-day precision ranging from 2.4 % to 11.2 % and inter-day precision ranging from 4.5 % to 16.1 %. Swine urine and bovine urine samples collected from different farms were effectively analyzed using the developed method, and metronidazole was detected in three swine urine samples.

Human red blood cell acetylcholinesterase activity: a revisit after fifteen years

Human red blood cell acetylcholinesterase (RBC-AChE) activity is valuable for detecting potential exposure to cholinesterase inhibiting substances (CIS). A reliable population-based RBC-AChE activity reference range is critical for early and massive clinical and occupational toxicology screening. Previous published studies were often limited to small numbers of subjects, various testing methods, and crude statistical data analyses. We tested 4818 adult subjects with a well-established 17-minute modified Michel method over a 2-year period. We conducted a retrospective data analysis and systematically investigated on the influences to testing values from gender, age, age group, and their combinations and interactions. No significant difference was observed in the testing values between males (mean, medium, interquartile range = 0.76, 0.76, 0.71-0.80 ΔpH/h, respectively) and females (mean, medium, interquartile range = 0.76, 0.76, 0.71-0.81 ΔpH/hour, respectively), when gender was the only factor considered (p = 0.7238). However, with age progression, male testing values exhibited a consistent upward trend, while females did not show any clear patterns. Linear regression analysis of the data revealed that gender, age, and age group more or less affected testing values either as independent variables or with their combinations and interactions. However, more potential factors need to be included to achieve better testing value predictions. We recommend the toxicological testing community to adopt a new set of age group specific RBC-AChE activity reference ranges for males (0.68-0.80, 0.69-0.81, 0.70-0.83, 0.71-0.84, and 0.73-0.87 ΔpH/h for 18-29, 30-39, 40-49, 50-59, and ≥60 years old, respectively) while keeping the current reference range (0.63-0.89 ΔpH/hour) for females.

Study on the toxicity prediction model ofacetolactate synthase inhibitor herbicides based on human serum albumin and superoxide dismutase binding information

Toxicity significantly influences the successful development of drugs. Based on the toxicity prediction method (carrier protein binding information-toxicity relationship) previously established by the our group, this paper introduces information on the interaction between pesticides and environmental markers (SOD) into the model for the first time, so that the toxicity prediction model can not only predict the toxicity of pesticides to humans and animals, but also predict the toxicity of pesticides to the environment. Firstly, the interaction of acetolactate synthase inhibitor herbicides (ALS inhibitor herbicides) with human serum albumin (HSA) and superoxide dismutase (SOD) was investigated systematically from theory combined with experiments by spectroscopy methods and molecular docking, and important fluorescence parameters were obtained. Then, the fluorescence parameters, pesticides acute toxicity LD50 and structural splitting information were used to construct predictive modeling of ALS inhibitor herbicides based on the carrier protein binding information (R2 = 0.977) and the predictive modeling of drug acute toxicity based on carrier protein binding information and conformational relationship (R2 = 0.991), which had effectively predicted pesticides toxicity in humans and animals. To predict potential environmental toxicity, the predictive modeling of drug acute toxicity based on superoxide dismutase binding information was established (R2 = 0.883) by ALS inhibitor herbicides-SOD binding information, which has a good predictive ability in the potential toxicity of pesticides to the environment. This study lays the foundation for developing low toxicity pesticides.

Human blood markers of cholinergic neurotoxicity and neuropathy: A useful guide for laboratory applications

Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are useful markers to assess the effects of exposure to anticholinesterase insecticides (Anti-AChE). In addition, lymphocyte neuropathy target esterase (LNTE) has been used as biomarker of neuropathic organophosphate compounds (OPs). Thus, this study evaluates the main types of circulating biomarkers related to the cholinergic system and to the neuropathy induced by OPs in standardized human samples. To achieve this objective, total protein of human plasma, erythrocytes and lymphocytes were first standardized, and then AChE, BChE and LNTE activities in human blood were evaluated in the presence of inhibitors. The acceptance criteria of the regulatory agency were respected with coefficients of regression of curves of 0.9972 for cholinesterase and 0.9956 for LNTE analyses. The wavelength established to perform cholinesterase assay was 450 nm and the time of incubation of the enzymes with inhibitors was 30 min. Differences were observed among the IC50 values regarding the in vitro inhibition of AChE, BChE and LNTE in the presence of OPs. In conclusion, the procedures demonstrated by the present work were simple, fast, inexpensive, sensitive, easy to be replicated and suitable to make conclusions about the neurotoxicity induced by Anti-AChE and neuropathic OPs.

Acute poisoning by chlorpyrifos differentially impacts survival and cardiorespiratory function in normotensive and hypertensive rats

Hypertension is the most important and well-known risk factor for cardiovascular disease (CVD). Recently, acute organophosphate (OP) poisoning has also been pointed as a CVD risk factor. Despite this evidence, no studies have contrasted the acute toxicosis and cardiovascular (CV) effects of OP poisoning under conditions of normotension and hypertension. In this work, adult male normotensive Wistar and Spontaneously Hypertensive rats (SHR) were intraperitoneally injected with saline or chlorpyrifos (CPF), an OP compound, monitored for acute toxicosis signs and 24-h survival. After poisoning, blood pressure, heart rate and ventilation were recorded, the Bezold-Jarisch Reflex (BJR), the Chemoreflex (CR) were chemically activated, as well as the cardiac autonomic tone (AUT) was assessed. Erythrocyte and brainstem acetylcholinesterase and plasmatic butyrylcholinesterase (BuChE) activities were measured as well as lipid peroxidation, advanced oxidation protein products (AOPP), nitrite/nitrate levels, expression of catalase, TNFα and angiotensin-I converting enzyme (ACE-1) within the brainstem. CPF induced a much more pronounced acute toxicosis and 33 % lethality in SHR. CPF poisoning impaired ventilation in SHR, the BJR reflex responses in Wistar rats, and the chemoreflex tachypneic response in both strains. CPF inhibited activity of cholinesterases in both strains, increased AOPP and nitrite/nitrate levels and expression of TNFα and ACE-1 in the brainstem of Wistar rats. Interestingly, SHR presented a reduced intrinsic BuChE activity, an important bioscavenger. Our findings show that, CPF at sublethal doses in normotensive rats lead to lethality and much more pronounced acute toxicity signs in the SHR. We also showed that cardiorespiratory reflexes were differentially impacted after CPF poisoning in both strains and that the cardiorespiratory disfunction seems to be associated with interference in cholinergic transmission, oxidative stress and inflammation. These results points to an increased susceptibility to acute toxicosis in hypertension, which may impose a significant risk to vulnerable populations.

Non-carcinogenic health risk from carbamate pesticide exposure of toddlers living in agricultural areas of Thailand

Toddlers in agricultural areas may be athave risk from pesticide exposure . A cross-sectional study was conducted with 130 toddlers and their caregivers. Face-to-face interviews were done to gather information about exposure factors. A wipe sampling technique was used to collect carbamate residues on each toddler's hands and feet. Results showed that there were carbamate residues on all wipe samples (100%), with a median concentration of 30.47 micrograms per sample (hands and feet). Carbamate residues detected on toddlers' hands and feetwere significantly associated (p < 0.05) with many factors, including the toddlers' relationships with caregivers, the education level of caregivers, the household incomes, the gender of toddlers, the frequency of following caregivers to farms, the frequency of foot washing, daytime activities, and playing durations. The health risk from dermal carbamate exposurewas above the acceptable range (HI = 3.244). Preventive measures should be considered to reduce toddlers' pesticide exposure in agricultural areas.

Mutagenicity, hepatotoxicity, and neurotoxicity of glyphosate and fipronil commercial formulations in Amazon turtles neonates (Podocnemis expansa)

Pesticides are considered one of the main causes of the population decline of reptiles worldwide, with freshwater turtles being particularly susceptible to aquatic contamination. In this context, we investigated the potential mutagenic, hepatotoxic, and neurotoxic effects in neonates of Podocnemis expansa exposed to substrate contaminated with different concentrations of glyphosate and/or fipronil during embryonic development. Eggs collected from the natural environment were artificially incubated in sand moistened with pure water, water added with glyphosate Atar 48® at concentrations of 65 and 6500 μg/L (groups G1 and G2, respectively), water added with fipronil Regent® 800WG at 4 and 400 μg/L (groups F1 and F2, respectively) and, water added with the combination of 65 μg/L glyphosate and 4 μg/L fipronil or with 6500 μg/L glyphosate and 400 μg/L fipronil (groups GF1 and GF2, respectively). For mutagenicity analysis, we evaluated the frequency of micronuclei (MN) and other erythrocyte nuclear abnormalities (ENAs), while for evaluation of hepatotoxicity and neurotoxicity, livers and encephalon were analyzed for histopathological alterations. Exposure to pesticides, alone or in combination, increased the frequency of erythrocyte nuclear abnormalities, particularly blebbed nuclei, moved nuclei, and notched nuclei. Individuals exposed to fipronil exhibited congestion and inflammatory infiltrate in their liver tissue, while, in the encephalon, congestion, and necrosis were present. Our study confirms that the incubation of eggs in substrate polluted with glyphosate and fipronil causes histopathological damage and mutagenic alteration in P. expansa, highlighting the importance of using different biomarkers to evaluate the ecotoxicological effects of these pesticides, especially in oviparous animals.

β-glucuronidase as a biomarker for assessing the exposure to anticholinergic pesticides: A meta-analysis

INTRODUCTION

The human exposure to anticholinergic pesticides has been associated with the development of various diseases. Therefore, several biomarkers have been proposed for biomonitoring human exposure to anticholinergic pesticides.

OBJECTIVE

This work evaluated the effect of human exposure to anticholinergic pesticides on β-glucuronidase (GUSB) levels.

METHODS

A systematic review was performed using PubMed, Web of Science, Scopus, and EBSCO databases up to December 2021. The statistical analysis employed standardized mean differences and meta-regression. And the trial sequential analysis was performed.

RESULTS

Nine studies were included. A monotonic relationship was observed between poisoning severity and GUSB. Furthermore, BuChE levels were correlated with GUSB levels.

CONCLUSIONS

The results indicated that GUSB levels could be used as a possible diagnosis biomarker in poisoning related to anticholinergic pesticide exposure. However, the use of GUSB to assess the chronic exposure to anticholinergic pesticides could be only performed in recent exposure (≈ 7 days after last exposure).

An Exploratory Study of the Metabolite Profiling from Pesticides Exposed Workers

Pesticides constitute a category of chemical products intended specifically for the control and mitigation of pests. With their constant increase in use, the risk to human health and the environment has increased proportionally due to occupational and environmental exposure to these compounds. The use of these chemicals is associated with several toxic effects related to acute and chronic toxicity, such as infertility, hormonal disorders and cancer. The present work aimed to study the metabolic profile of individuals occupationally exposed to pesticides, using a metabolomics tool to identify potential new biomarkers. Metabolomics analysis was carried out on plasma and urine samples from individuals exposed and non-exposed occupationally, using liquid chromatography coupled with mass spectrometry (UPLC-MS). Non-targeted metabolomics analysis, using principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA) or partial least squares discriminant orthogonal analysis (OPLS-DA), demonstrated good separation of the samples and identified 21 discriminating metabolites in plasma and 17 in urine. The analysis of the ROC curve indicated the compounds with the greatest potential for biomarkers. Comprehensive analysis of the metabolic pathways influenced by exposure to pesticides revealed alterations, mainly in lipid and amino acid metabolism. This study indicates that the use of metabolomics provides important information about complex biological responses.

The protective effects of baicalin and chrysin against emamectin benzoate-induced toxicity in Wistar albino rats

The aim of this study was to investigate the effects of baicalin, chrysin and their combinations against emamectin benzoate-induced toxicity in rats. For this purpose, sixty four rats were divided into evenly 8 groups with 6-8-week-old male Wistar albino rats, weighing 180-250 g, in each group. While the first group was kept as a control (corn oil), the remaining 7 groups were administered with emamectin benzoate (10 mg/kg bw), baicalin (50 mg/kg bw) and chrysin (50 mg/kg bw) alone or together for 28 days. Oxidative stress parameters, serum biochemical parameters and blood/tissue (liver, kidney, brain, testis and heart) and tissue histopathology were investigated. Compared to the control group, the emamectin benzoate-intoxicated rats had significantly higher tissue/plasma concentrations of nitric oxide (NO) and malondialdehyde (MDA), as well as lower tissue glutathione (GSH) concentrations and antioxidant enzyme activity (glutathione peroxidase/GSH-Px, glutathione reductase/GR, glutathione-S-transferase/GST, superoxide dismutase/SOD, catalase/CAT). Biochemical analysis showed that emamectin benzoate administration significantly increased serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) activities, as well as triglyceride, cholesterol, creatinine, uric acid and urea levels, and decreased serum total protein and albumin levels. The histopathological examination of the liver, kidney, brain, heart and testis tissues of the emamectin benzoate-intoxicated rats demonstrated necrotic changes. Baicalin and/or chrysin reversed the biochemical and histopathological alterations induced by emamectin benzoate on these tested organs. Therefore, baicalin and chrysin (alone or in combination) could offer protection against emamectin benzoate-induced toxicity.

Evaluating how occupational exposure to organophosphates and pyrethroids impacts ADHD severity in Egyptian male adolescents

BACKGROUND

Attention Deficit/Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder characterized by deficits in attention and hyperactivity/impulsivity that cause impairments to daily living. An area of long-standing concern is understanding links between environmental toxicants, including pesticides, and the development or worsening of ADHD.

OBJECTIVES

The present study evaluated associations between occupational pesticide exposure, specifically organophosphate (OP) pesticides, chlorpyrifos (CPF) and the pyrethroids (PYR) alpha-cypermethrin (αCM) and lambda-cyhalothrin (λCH), and symptoms of ADHD in a longitudinal study among Egyptian adolescent males.

METHODS

Participants (N = 226, mean age = 17) were Egyptian adolescent males who either applied pesticides or were non-applicators. Urinary trichloro-2-pyridinol (TCPy) was measured as a specific metabolite biomarker of exposure to chlorpyrifos. Urinary 3-phenoxybenzoic acid (3-PBA) was measured as a general metabolite biomarker of exposure to pyrethroids, while urinary cis-3-(2,2- dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid (cis-DCCA) was measured as a specific biomarker of exposure to αCM and lambda cyhalothric acid (λCH acid) measured as a specific biomarker of exposure to λCH. Ordinal logistic regression models controlling for age were used to determine the likelihood of ADHD development (measured via parent-reported ADHD symptoms) as the level of biomarkers of pesticide exposure increased.

RESULTS

Cis-DCCA was the only biomarker associated with higher likelihood ADHD symptoms (> 0.60 vs. 0-0.17 μg/g creatinine; OR = 2.82, 95% CI: 1.29-6.14). All participants reported clinical levels of ADHD symptoms when compared to national norms used in the United States. TCPy, trans-DCCA and λCH acid were not associated with risk of ADHD symptoms after controlling for levels of cis-DCCA. No other metabolites were associated with the number of ADHD symptoms. There were no interaction effects found for exposure to both OPs and Pyrethroids.

DISCUSSION

The results suggest that exposure to the pyrethroid αCM is associated with more ADHD symptoms. Methodological and cultural considerations in need of further study are discussed.

Relationship between Butyrylcholinesterase Activity and Cognitive Ability in Workers Exposed to Chlorpyrifos

Background. The use of Chlorpyrifos leads to a public, environmental, and occupational health problem associated with adverse effects in the exposed population, generating alterations mainly in the central nervous system, such as cognitive function. This study aimed to estimate the association between butyrylcholinesterase activity (BChE) and cognitive ability in workers exposed to chlorpyrifos. Methods. We designed a cross-sectional study, where we measured BChE in serum samples as an indicator of exposure to chlorpyrifos. The cognitive ability was assessed by the mean score of the Peruvian version of the Mini-Mental State Examination (MMSE). We also used a questionary to collect demographic and occupational information. Results. We evaluated 120 farmers with a predominance of males (92%) and a mean age of 32.1 ± 9.0 years. We found most of the workers in fumigation activities (84%). The mean BChE was 6144.7 ± 2355.0 U/L, and 46% presented inhibition enzyme (<5500 U/L). The median MMSE score was 28 (interquartile range: 26.5–31.5; 6% showed an alteration in cognitive ability (score < 24)). The MMSE test found a significant association between BChE inhibition and MMSE score (β: −0.071, 95%CI: −0.108 to −0.025). Conclusion. In this study, 45.8% of workers exposed to chlorpyriphos presented BChE inhibition. The BChE inhibition is significantly associated with the MMSE score in workers exposed to chlorpyrifos.

Household prallethrin-based insecticide toxicity on different C. elegans life stage: A possible sign of Huntington Disease

Household insecticide is largely used for insect and ectoparasite control, in city centers as well as in the countryside. The pyrethroids are the most used class of insecticide, these compounds in low doses have low toxicity for mammalians, in comparison to other compounds, with insecticide effects. The contact of these compounds in sublethal doses begins in early life and many cases, in intrauterine life. Considerable diseases still with undefined etiology, such as neurodegenerative conditions, and Huntington's Disease (HD) is one of them. HD is related to overexpression of Polyglutamine (PolyQ40), its aggregation, and non-solubilization, which leads to neural, behavioral, and cognitive damage. In our study, we evaluate the effect of two sublethal doses of a prallethrin-based insecticide (P-BI), in three different Caenorhabditis elegans life stages transgenerational, neonatal, and lifespan. We evaluated the Body bends and pharyngeal pumping rate, and social feeding as behavioral biomarkers. As well as acetylcholinesterase activity (AChE), PolyQ40 aggregation, antioxidant enzymes, and heat shock protein (HSP) expression. We observe that the toxic effect of P-BI is more pronounced on transgenerational and lifespan exposure. Both sublethal doses of P-BI decreased the AChE activity and retard the HSP expression as well as increased the PolyQ40 aggregates indicating a clear biomarker for possible effect in the progression of the HD, by the environmental contamination.

The protective effect of chrysin against oxidative stress and organ toxicity in rats exposed to propetamphos

The aim of this study was to investigate the protective efficacy of chrysin against propetamphos exposure. For this purpose, 2 to 3-month-old 40 male Wistar Albino rats were used. These animals were randomly assigned to four groups. The animals in the control group received the vehicle substance (corn oil) alone. Groups 2, 3 and 4 were administered with 50 mg/kg.bw/day of chrysin (in corn oil), 10 mg/kg.bw/day of propetamphos (in corn oil), and 10 mg/kg.bw/day of propetamphos plus 50 mg/kg.bw/day of chrysin, respectively, for 28 days. Some oxidative stress/lipid peroxidation parameters (MDA, SOD, CAT, GSH-Px, NO, glutathione) and serum biochemical parameters (triglyceride, cholesterol, creatinine, BUN, creatine phosphokinase, ALT, ALP and pseudocholinesterase) were analyzed in tissue/blood samples. Also, histopathological findings were observed. According to the data obtained, no significant alteration had occurred in these parameters and the histological findings in the group given chrysin alone, when compared to the control group. Significant unfavorable alterations were detected in the oxidative stress/lipid peroxidation/antioxidant status parameters, all biochemical parameters and histopathological findings of the group that received propetamphos alone. In the group that was given both chrysin and propetamphos, remedial/recovery alterations were observed in the oxidative stress/lipid peroxidation/antioxidant status values, serum biochemical parameters and histopathological findings, such that the values and histopathological findings showed partly similarity to those of the control group. In result, it is suggested that chrysin may provide protection against propetamphos exposure and propetamphos-induced organ damage in rats at a certain level.

Urinary metabolites of diazinon and chlorpyrifos in sprayer operators and farm workers of a potato farm

In order to investigate the effect of diazinon and chlorpyrifos on agricultural workers exposed to pesticides, urinary metabolites 2-Isopropyl-6-methyl-4-pyrimidinol (IMPy) and 3,5,6-Trichloro-2-pyridinol (TPCy) in farm workers, sprayer operators, and non-exposed people as a control group were measured. The modified QuEChERS method was applied to extract samples and was measured using a gas chromatograph/nitrogen-phosphorus detector. The obtained results showed that the median concentrations of TCPy were 36.92-547.7 and 7.7-49.58 ng/mL for sprayer operators and farm workers, respectively. Moreover, the median concentrations of IMPy were 81.66-593.1 ng/mL for sprayer operators and 40.6-66.1 ng/mL for farm workers. The control group had no measurable metabolites. The IMPy level of 60% of sprayer operators was significantly higher (P ˂ 0.05) than the TCPy level. The analysis of variance highlighted the significant relationship (P ˂ 0.05) between the levels of each metabolite and the use of safety gloves, respiratory masks, safety goggles, working time per week, and type of insecticide exposure. Our findings revealed the need to measure the urinary metabolites of these insecticides in other exposed workers. Also, workers should be taught the impact of using personal protective equipment.

Improving the Risk Assessment of Pesticides through the Integration of Human Biomonitoring and Food Monitoring Data: A Case Study for Chlorpyrifos

The risk assessment of pesticide residues in food is a key priority in the area of food safety. Most jurisdictions have implemented pre-marketing authorization processes, which are supported by prospective risk assessments. These prospective assessments estimate the expected residue levels in food combining results from residue trials, resembling the pesticide use patterns, with food consumption patterns, according to internationally agreed procedures. In addition, jurisdictions such as the European Union (EU) have implemented large monitoring programs, measuring actual pesticide residue levels in food, and are supporting large-scale human biomonitoring programs for confirming the actual exposure levels and potential risk for consumers. The organophosphate insecticide chlorpyrifos offers an interesting case study, as in the last decade, its acceptable daily intake (ADI) has been reduced several times following risk assessments by the European Food Safety Authority (EFSA). This process has been linked to significant reductions in the use authorized in the EU, reducing consumers’ exposure progressively, until the final ban in 2020, accompanied by setting all EU maximum residue levels (MRL) in food at the default value of 0.01 mg/kg. We present a comparison of estimates of the consumer’s internal exposure to chlorpyrifos based on the urinary marker 3,5,6-trichloro-2-pyridinol (TCPy), using two sources of monitoring data: monitoring of the food chain from the EU program and biomonitoring of European citizens from the HB4EU project, supported by a literature search. Both methods confirmed a drastic reduction in exposure levels from 2016 onwards. The margin of exposure approach is then used for conducting retrospective risk assessments at different time points, considering the evolution of our understanding of chlorpyrifos toxicity, as well as of exposure levels in EU consumers following the regulatory decisions. Concerns are presented using a color code, and have been identified for almost all studies, particularly for the highest exposed group, but at different levels, reaching the maximum level, red code, for children in Cyprus and Israel. The assessment uncertainties are highlighted and integrated in the identification of levels of concern.

Non-occupational exposure to pesticides and health markers in general population in Northern Finland: Differences between sexes

BACKGROUND

Occupational exposure to pesticides has been reported among general population worldwide. However, little is known about the associations between non-occupational exposure to pesticides, and biological markers of health and their response by sex.

OBJECTIVES

We aimed to assess the associations between non-occupational overall pesticide exposure, length of exposure and specific pesticides reported with 35 biological markers of health representing cardiometabolic, haematological, lung function, sex hormones, liver and kidney function profiles, and vitamin D in Finnish cohort.

METHODS

31-year cross-sectional examination of the Northern Finland Birth Cohort 1966 provided blood samples for biomarker measurements in 1997-1998. Number of subjects varied between 2361 and 5037 for given exposures and certain outcome associations. Multivariable regression analyses were performed to examine associations between overall pesticide exposure (OPE), length of pesticide exposure in months (PEM), in years (PEY), and specific pesticides use (PEU) or not with cardiometabolic [SBP, DBP, TC, LDL, HDL, triglycerides, fasting glucose, insulin, HOMA-IR, HOMA-B, HOMA-S, hs-CRP], hematological [WBC, RBC, Hb, HCT, MCV, MCH, MCHC, platelets], lung function (FVC, FEV1), sex hormones [luteinizing hormone (LH), testosterone (TT), sex-hormone binding globulin (SHBG)], liver and kidney function profiles [total protein, albumin, globulin, ALP, ALT, GGT, urea, creatinine], and vitamin D adjusting for sex, BMI, socioeconomic position (SEP) and season of pesticide use.

RESULTS

This cohort study on up to 5037 adults with non-occupational OPE, PEM, PEY and PEU differed by sex and SEP. In regression analyses, all the exposures were positively associated with total cholesterol and low-density lipoprotein cholesterol, and PEU was negatively associated with high-density lipoprotein cholesterol in females. OPE and PEM were positively associated with haematocrit in females and PEU with platelets in males. PEU was negatively associated with mean corpuscular haemoglobin. OPE and PEM were positively associated with LH in males. OPE was negatively associated with total protein and albumin in males.

DISCUSSION

In Finnish young adults, non-occupational overall pesticide exposure, length of exposure and specific pesticides were associated with multiple biological markers of health. The biological markers seem to be indicative of adverse effects of pesticides and warrant for further studies to replicate the findings and determine the underlying mechanisms.

Non-Occupational Exposure to Pesticides: Experimental Approaches and Analytical Techniques (from 2019)

BACKGROUND

Pesticide residues are a threat to the health of the global population, not only to farmers, applicators, and other pesticide professionals. Humans are exposed through various routes such as food, skin, and inhalation. This study summarizes the different methods to assess and/or estimate human exposure to pesticide residues of the global population.

METHODS

A systematic search was carried out on Scopus and web of science databases of studies on human exposure to pesticide residues since 2019.

RESULTS

The methods to estimate human health risk can be categorized as direct (determining the exposure through specific biomarkers in human matrices) or indirect (determining the levels in the environment and food and estimating the occurrence). The role that analytical techniques play was analyzed. In both cases, the application of generic solvent extraction and solid-phase extraction (SPE) clean-up, followed by liquid or gas chromatography coupled to mass spectrometry, is decisive. Advances within the analytical techniques have played an unquestionable role.

CONCLUSIONS

All these studies have contributed to an important advance in the knowledge of analytical techniques for the detection of pesticide levels and the subsequent assessment of nonoccupational human exposure.

Recent Advances on Detection of Insecticides Using Optical Sensors

Insecticides are enormously important to industry requirements and market demands in agriculture. Despite their usefulness, these insecticides can pose a dangerous risk to the safety of food, environment and all living things through various mechanisms of action. Concern about the environmental impact of repeated use of insecticides has prompted many researchers to develop rapid, economical, uncomplicated and user-friendly analytical method for the detection of insecticides. In this regards, optical sensors are considered as favorable methods for insecticides analysis because of their special features including rapid detection time, low cost, easy to use and high selectivity and sensitivity. In this review, current progresses of incorporation between recognition elements and optical sensors for insecticide detection are discussed and evaluated well, by categorizing it based on insecticide chemical classes, including the range of detection and limit of detection. Additionally, this review aims to provide powerful insights to researchers for the future development of optical sensors in the detection of insecticides.

Elucidating pesticide sensitivity of two endogeic earthworm species through the interplay between esterases and glutathione S-transferases

Earthworms are common organisms in soil toxicity-testing framework, and endogeic species are currently recommended due to their ecological role in agroecosystem. However, little is known on their pesticide metabolic capacities. We firstly compared the baseline activity of B-esterases and glutathione-S-transferase in Allolobophora chlorotica and Aporrectodea caliginosa. Secondly, vulnerability of these species to pesticide exposure was assessed by in vitro trials using the organophosphate (OP) chlorpyrifos-ethyl-oxon (CPOx) and ethyl-paraoxon (POx), and by short-term (7 days) in vivo metabolic responses in soil contaminated with pesticides. Among B-esterases, acetylcholinesterase (AChE) activity was abundant in the microsomal fraction (80% and 70% of total activity for A. caliginosa and A. chlorotica, respectively). Carboxylesterase (CbE) activities were measured using three substrates to examine species differences in isoenzyme and sensitivity to both in vitro and in vivo exposure. CbEs were mainly found in the cytosolic fraction (80% and 60% for A. caliginosa and A. chlorotica respectively). GST was exclusively found in the soluble fraction for both species. Both OPs inhibited B-esterases in a concentration-dependent manner. In vitro trials revealed a pesticide-specific response, being A. chlorotica AChE more sensitive to CPOx compared to POx. CbE activity was inhibited at the same extent in both species. The 7-d exposure showed A. chlorotica less sensitive to both OPs, which contrasted with outcomes from in vitro experiments. This non-related functional between both approaches for assessing pesticide toxicity suggests that other mechanisms linked with in vivo OP bioactivation and excretion could have a significant role in the OP toxicity in endogeic earthworms.

Occupational exposure to pesticides: Genetic danger to farmworkers and manufacturing workers - A meta-analytical review

In the last decades, the use of pesticides has grown worldwide. However, there is great worry about the impact of pesticides on human health, due to their wide distribution and possible long-term effects. Complex mixtures with different formulations are often used, including a variety of genotoxic compounds. Thus, genotoxicity tests form an important part of cancer research and risk assessment of potential carcinogens. This study aimed to conduct a meta-analytical review of possible genetic damage resulting from occupational exposure in farmworkers and workers employed in pesticide production, both ever in comparison to non-exposed people, using comet assay (CA), micronucleus test (MN) and telomere length (TL) data available in the scientific literature. A total of 145 datasets were evaluated. The results showed that the occupationally exposed workers had more DNA damage in CA and MN than non-exposed workers. The TL result did not show difference between groups. When the data were categorized by gender (male, female or both), crop (general, tobacco, fruits, soybeans, cotton) and occupation (manufacturing or farmworkers), the study found that the exposed group always presented higher damage than the non-exposed individuals, in CA and MN. More studies with TL are needed to obtain a more precise response, and to segregate the effect of tobacco farming from pesticide exposure. When TL was segregated by gender, women and men presented difference between exposed and non-exposed groups. In general, the publication bias impact was modest. If all relevant studies were included, the key finding (i.e. the effect of pesticide exposure increases the genotoxicity and mutation rate) would probably remain unchanged. Lastly, it is important to highlight the importance of the use of personal protective equipment (PPE), and offer safer options to farmworkers (e.g. organic farming or less toxic alternatives).

Morpho-Functional Alterations in the Gills of a Seawater Teleost, the Ornate Wrasse (Thalassoma pavo L.), after Short-Term Exposure to Chlorpyrifos

Chlorpyrifos (CPF) is an organophosphorus insecticide commonly used for domestic and agricultural purposes. The risk posed by environmental contamination from CPF is well acknowledged, and it has been detected worldwide in aquatic habitats and coastal areas. In addition, due to its slower degradation in seawater compared to freshwater, CPF is of particular concern for marine environments. Here, we investigated for the first time the morpho-functional alterations induced by CPF on the gills of Thalassoma pavo, a widespread species in the Mediterranean Sea. We tested the effects of two sublethal concentrations (4 and 8 µg/L) after 48 and 96 h. Our study demonstrates that the alterations induced by CPF are dose and time-dependent and highlight the harmful properties of this insecticide. After exposure to the low tested concentration, the more frequent alteration is an intense proliferation of the primary epithelium, whereas after exposure to the high concentration, the primary epithelium proliferation is less extensive, and the most evident effects are the thinning of secondary lamellae and the ectopia of chloride and goblet cells. CPF also modulated the expression of Na⁺/K⁺-ATPase. Dilation of lamellar apical tips, pillar cell degeneration, and appearance of aneurysms are often observed.

Risk assessment of the chiral pesticide fenamiphos in a human model: Cytochrome P450 phenotyping and inhibition studies

Fenamiphos (FS) is a chiral organophosphate pesticide that is used to control nematodes in several crops. Enantioselective differences may be observed in FS activity, bioaccumulation, metabolism, and toxicity. Humans may be exposed to FS through occupational and chronic (food, water, and environmental) exposure. FS may cause undesirable CYP450 pesticide-drug interactions, which may impact human health. Here, the CYP450 isoforms involved in enantioselective FS metabolism were identified, and CYP450 inhibition by rac-FS, (+)-FS, and (-)-FS was evaluated to obtain reliable information on enantioselective FS risk assessment in humans. CYP3A4 and CYP2E1 metabolized FS enantiomers, and CYP2B6 may participate in rac-FS metabolism. In addition, rac-FS, (+)-FS, and (-)-FS were reversible competitive CYP1A2, CYP2C19, and CYP3A4/5 inhibitors. High stereoselective inhibition potential was verified; rac-FS and (-)-FS strongly inhibited and (+)-FS moderately inhibited CYP1A2. Stereoselective differences were also detected for CYP2C19 and CYP3A4/5, which were strongly inhibited by rac-FS, (+)-FS, and (-)-FS. Our results indicated a high potential for CYP450 drug-pesticide interactions, which may affect human health. The lack of stereoselective research on the effect of chiral pesticides on the activity of CYP450 isoforms highlights the importance of assessing the risks of such pesticides in humans.