Effect of chronic pesticide exposure in farm workers of a Mexico community

Pesticide Exposure in the Cultivation of Carica papaya L. and Capsicum annuum L. in Rural Areas of Oaxaca, Mexico

This study focuses on describing the diversity of pesticides, the knowledge and behaviors of their use, and the acute poisoning symptoms (APS) derived from their exposure from two agricultural production systems (papaya-Carica papaya L.- and chili-Capsicum annuum L.-) in Oaxaca, Mexico. Through surveys, sociodemographic information, characteristics of the production system, knowledge and behaviors in the handling of pesticides, and APS perceived by users were captured. Papaya producers are younger, have fewer years of activity, and have larger agricultural areas than chili producers. Insect attacks and diseases are an essential factor for the application of pesticides. Thirty-one active ingredients (Ais) were identified in papaya and thirty-seven in chili, predominantly insecticides and fungicides of toxicological category IV. Approximately 50% of users apply mixtures of different Ais, have little knowledge and inappropriate behavior in their handling, and report up to five acute pesticide poisoning symptoms, mainly burning and irritation of the skin, burning eyes, itchy skin, runny nose, headache, and watery eyes. The production of papaya and chili are relevant activities for generating economic income, but they risk the producer's and their family's health. Both systems are a potential scenario for the manifestation of diseases due to exposure to pesticides in the medium and long term.

Effects of glyphosate exposure on western diet-induced non-alcoholic fatty liver disease in mice

We evaluated whether glyphosate promotes western diet (WD)-induced non-alcoholic fatty liver disease (NAFLD). Male C57BL/6J mice were fed WD and received intragastrical glyphosate (0.05, 5 or 50 mg/kg) for 6 months. Glyphosate did not promote WD-induced obesity, hypercholesterolemia, glucose intolerance, hepatic steatosis, and fibrosis. Nonetheless, the higher dose (50 mg) enhanced hepatic CD68+ macrophage density, p65, TNF-α, and IL-6 protein levels. Furthermore, this dose decreased hepatic Nrf2 levels, while enhancing lipid peroxidation in the liver and adipose tissue. Hepatic transcriptome revealed that glyphosate at 50 mg upregulated 212 genes and downregulated 731 genes. Genes associated with oxidative stress and inflammation were upregulated, while key cell cycle-related genes were downregulated. Our results indicate that glyphosate exposure - in a dose within the toxicological limits - impairs hepatic inflammation/redox dynamics in a NAFLD microenvironment.

Medicinal herbs and multiple sclerosis: Overview on the hard balance between new therapeutic strategy and occupational health risk

Multiple sclerosis (MS) is an autoimmune disease characterized by demyelination and axonal loss of the central nervous system (CNS). Despite its spread throughout the world, the mechanisms that determine its onset are still to be defined. Immunological, genetic, viral, and environmental factors and exposure to chemicals may trigger MS. Many studies have highlighted the anti-inflammatory and anti-oxidant effects of medicinal herbs, which make them a natural and complementary treatment for neurodegenerative diseases. A severe reduction of several MS symptoms occurs with herbal therapy. Thus, the request for medicinal plants with potential beneficial effects, for MS patients, is constantly increasing. Consequently, a production increase needs. Unfortunately, many medicinal herbs were untested and their action mechanism, possible adverse effects, contraindications, or interactions with other drugs, are poorly or not investigated. Keeping in mind the pathological mechanisms of MS and the oxidative damages and mitochondrial dysfunctions induced by pesticides, it is important to understand if pesticides used to increase agricultural productivity and their residues in medicinal plants, may increase the risk of developing MS in both workers and consumers. Studies providing some indication about the relationship between environmental exposure to pesticides and MS disease incidence are few, fragmentary, and discordant. The aim of this article is to provide a glance at the therapeutic potential of medicinal plants and at the risk for MS onset of pesticides used by medicinal plant growers and present in medicinal herbs.

Health Effects of Pesticide Exposure in Latin American and the Caribbean Populations: A Scoping Review

BACKGROUND

Multiple epidemiological studies have shown that exposure to pesticides is associated with adverse health outcomes. However, the literature on pesticide-related health effects in the Latin American and the Caribbean (LAC) region, an area of intensive agricultural and residential pesticide use, is sparse. We conducted a scoping review to describe the current state of research on the health effects of pesticide exposure in LAC populations with the goal of identifying knowledge gaps and research capacity building needs.

METHODS

We searched PubMed and SciELO for epidemiological studies on pesticide exposure and human health in LAC populations published between January 2007 and December 2021. We identified 233 publications from 16 countries that met our inclusion criteria and grouped them by health outcome (genotoxicity, neurobehavioral outcomes, placental outcomes and teratogenicity, cancer, thyroid function, reproductive outcomes, birth outcomes and child growth, and others).

RESULTS

Most published studies were conducted in Brazil (37%, n = 88 ) and Mexico (20%, n = 46 ), were cross-sectional in design (72%, n = 167 ), and focused on farmworkers (45%, n = 105 ) or children (21%, n = 48 ). The most frequently studied health effects included genotoxicity (24%, n = 62 ) and neurobehavioral outcomes (21%, n = 54 ), and organophosphate (OP) pesticides were the most frequently examined (26%, n = 81 ). Forty-seven percent (n = 112 ) of the studies relied only on indirect pesticide exposure assessment methods. Exposure to OP pesticides, carbamates, or to multiple pesticide classes was consistently associated with markers of genotoxicity and adverse neurobehavioral outcomes, particularly among children and farmworkers.

DISCUSSION

Our scoping review provides some evidence that exposure to pesticides may adversely impact the health of LAC populations, but methodological limitations and inconsistencies undermine the strength of the conclusions. It is critical to increase capacity building, integrate research initiatives, and conduct more rigorous epidemiological studies in the region to address these limitations, better inform public health surveillance systems, and maximize the impact of research on public policies. https://doi.org/10.1289/EHP9934.

Maternal pesticides exposure in pregnancy and the risk of wheezing in infancy: A prospective cohort study

INTRODUCTION

Pesticide exposure in pregnancy may have health effects in the offspring. We studied whether maternal pesticides exposure during pregnancy is associated with infant wheezing.

METHODS

The study involved 5997 children from the Italian NINFEA birth cohort, whose mothers were recruited during pregnancy between 2005 and 2016. We used questionnaires completed during pregnancy and 6 months after delivery to derive the following indirect measures of exposure: i) Self-reported pesticide use during the first and the third trimester of pregnancy; (ii) Agricultural activities during the same trimesters. We also evaluated the exposure to agricultural pesticides applied near home using the Corine Land Cover inventory to derive the proportion of a 200-metre buffer area around maternal home address covered by agricultural crops and specific crop types (arable land, fruit trees, heterogeneous cultivations). Questionnaires completed when the child turned 18 months reported information on wheezing between 6 and 18 months of age. We estimated the odds ratios of wheezing adjusting for the following maternal characteristics: age, education, parity, asthma, atopy, smoking in pregnancy, region and area of residence, pet ownership during pregnancy. Crops proximity analyses were restricted to residents in rural areas (N = 1674).

RESULTS

Agricultural activities during pregnancy were not associated with infant wheezing. Compared to no pesticide use, there was a weak positive association for self-reported use in the third trimester (POR: 1.30; 95 %CI 0.95-1.78) and a stronger association for use in both trimesters (POR: 1.72; 95 %CI 1.11-2.65). The relationship between the proportion of crops around the home address and the risk of infant wheezing, was J-shaped, in particular for fruit trees with the lowest risk for mid values and elevated risk for higher values.

CONCLUSION

We found some evidence of association for maternal pesticide use in pregnancy and residential proximity to fruit trees cultivations with infant wheezing.

A Systematic Review of Studies on Genotoxicity and Related Biomarkers in Populations Exposed to Pesticides in Mexico

In agricultural activities, pest control is essential, and the most effective method is the use of chemical agents that also represent an important source of exposure to potentially toxic compounds. Pesticides constitute a heterogeneous group of compounds designed specifically to control different pests. Besides measuring their levels or that of their metabolites in air, plasma, serum, blood, urine, etc., some studies reported increased DNA damage levels after occupational or environmental pesticides exposure, evidenced by several cytogenetic biomarkers such as chromosomal aberrations (CA), sister chromatid exchanges (SCE), micronuclei frequency (MN) together with other nuclear abnormalities (NA), alkaline comet assay, but also changes in oxidative stress parameters and miRNA levels. Single or combined, these techniques have also been used in genotoxic biomonitoring studies of workers occupationally exposed to pesticides in Mexico. Despite being a country with great agricultural activity and reported excessive pesticide use, genotoxic studies have been relatively few and, in some cases, contradictory. A review was made of the studies available (published until the end of 2020 on PubMed, Web of Science, Redalyc and Scielo, both in English and Spanish) in the scientific literature that evaluated occupational exposure of human samples to pesticides assessed with DNA damage and related biomarkers in Mexico.

The palliative effect of camel milk on hepatic CYP1A1 gene expression and DNA damage induced by fenpropathrin oral intoxication in male rats

The present study investigated the alleviating role of camel milk (CM) in the mitigation of fenpropathrin (FNP) type II pyrethroid induced oxidative stress, alterations of hepatic (CYP1A1) mRNA expression pattern, and DNA damage using the alkaline comet assay (SCGE) in male rats. Sixty male Sprague-Dawley rats were separated into six groups (n = 10): 1st control (C), 2nd corn oil (CO), 3rd (CM): gavaged CM 2ml/rat, 4th (FNP): gavaged FNP 7.09 mg/kg body weight (BW), 5th (FNP pro/co-treated): gavaged CM firstly for 15 days, then CM + FNP by the same mentioned doses and route, 6th (FNP + CM co-treated): gavaged FNP firstly followed by CM by the same mentioned doses and route. Rats were orally gavaged three times per week, day after day for 60 days. FNP exposure significantly reduced serum glutathione (GSH) levels, but significantly increased serum levels of superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), protein carbonyl (PCO), and 8hydroxy2deoxyguanosine (8OH2dG). Additionally, FNP exposure significantly up-regulated the mRNA expression levels of hepatic CYP1A1 and increased the SCGE indices in whole blood, liver, and spleen tissues of exposed male rats. Administration of CM significantly regulated the FNP induced oxidative stress, reduced hepatic CYP1A1 mRNA expression levels and values of comet assay indices particularly in the (CM + FNP pro/co-treated) group compared to the (FNP + CM co-treated) group. In conclusion, our results indicate, for the first time, that FNP retains an in vivo genotoxic potential at a dose of (1/10 LD₅₀) and up-regulated hepatic CYP1A1 mRNA expression in male rats. Additionally, CM supplements may improve the genotoxic outcomes, oxidative stress, and altered CYP1A1 mRNA expression induced by FNP particularly in the pro/concurrent-treatment compared to the concurrent treatment alone.

Synthesis of Fe3O4/CdS-ZnS nanostructure and its application for photocatalytic degradation of chlorpyrifos pesticide and brilliant green dye from aqueous solutions

Chlorpyrifos (CP) is an organophosphorus pesticide used to control pests in agriculture. Brilliant green (BG) is a cationic dye widely used in textile and dyeing industry. However, the presence of pollutants in the aquatic environment has harmful effects on the environment and humans. Photocatalytic degradation can be appropriate method for water purification. Therefore, the Fe₃O₄/CdS-ZnS magnetic nanocomposite was synthesized and characterized by Brunauer-Emmett-Teller (BET) surface area analysis, Energy dispersive x-ray spectroscopy (EDX), X-ray diffraction (XRD), vibrating sample magnetometry (VSM), UV-Vis-diffuse reflectance spectroscopy (DRS), and field emission scanning electron microscopy (FESEM) analyses and was used to degrade pollutants such as chlorpyrifos pesticide and brilliant green dye under visible light with source 300 W. Parameters that may be effective on photocatalytic degradation include pH, photocatalyst amount, contaminant concentration, photocatalyst and contaminant contact temperature and duration, light intensity as well as distance of light source from the reaction vessel. In the present study, the parameters that have the most influence on the degradation process were experimentally optimized, including pH, photocatalyst amount, photocatalyst reuse, and initial concentration. The study of the photocatalytic degradation rate of chlorpyrifos and brilliant green in optimal conditions (pH = 7, the concentration of pollutants = 10 ppm, volume of pollutants = 5 mL, and photocatalyst amounts for CP and BG were 0.0100 and 0.0015 g respectively) was obtained by Langmuir-Hinshelwood model. According to this model, the k_app value for CP and BG were respectively 0.0315 and 0.0119 min^-1 respectively. It has been concluded that the composition of CdS and ZnS caused inhibition of the recombination of photogenerated charge carriers, leading to high catalytic efficiency. Based on the results, the synthesized nanocatalyst showed that it has the ability to photocatalytic degradation of chlorpyrifos and brilliant green in aqueous solutions.

Practice towards pesticide handling, storage and its associated factors among farmers working in irrigations in Gondar town, Ethiopia, 2019

OBJECTIVES

The main objective of this study was to assess pesticide handling and storage practice, and its associated factors among farmers engaged in irrigation in Gondar town, Ethiopia, 2019. Community-based cross-sectional study was used to assess pesticide handling and storage practice, and its associated factors among farmers. Simple random sampling technique was used to select study subjects. Semi-structured questionnaires were used to collect data. Data were entered using Epi Info 7.0 and exported to SPSS 20. Descriptive statistics were used for some variables. Univariate and multivariable binary logistic regression was used to test the factors associated with the outcome. Adjusted odd ratio (AOR) and 95% confidence interval (CI) with P value less than 0.05 were used to report association.

RESULTS

About 409 study subjects completed the semi-structured questionnaires. Among the studies subjects, 261 (63.8%) of them had poor pesticide handling and storage practice. Knowledge [AOR = 3.23 (95% CI 1.91, 5.46)], attitude [AOR = 1.77 (95% CI 1.11, 2.81) and educational status (informal education [AOR = 3.05 (95% CI 1.72, 5.42)], elementary education [AOR = 5.38 (95% CI 2.62, 11.06)], secondary education [AOR = 9.51 (95% CI 4.24, 21.32)] and certificate and above [AOR = 6.00 (95% CI 1.58, 22.78)]) were factors significantly associated with pesticide handling and storage practice. To improve the pesticide handling and storage practice, it is imperative to enhance the level of the farmer's knowledge through training, and information dissemination in workshops.

High Incidence of Moderately Reduced Renal Function and Lead Bioaccumulation in Agricultural Workers in Assin South District, Ghana: A Community-Based Case-Control Study

Background

The quest to enhance agricultural productivity and crop yields has led to increased use of agrochemicals on a global scale. Long-term use of these agrochemicals may be associated with adverse health implications.

Objective

To assess haematological indices, renal function, heavy metal bioaccumulation in farmers and sprayers, and their use of personal protective equipment (PPE).

Materials and Methods

This community-based case-control study was conducted from January 2018 to June 2018 in the Assin South District, Central Region, Ghana. A total of 144 participants were conveniently sampled: 83 agricultural workers (cases) and 61 indigenes with no direct exposure to agrochemicals (controls). Structured questionnaire was used to obtain demographic data as well as agricultural work practices followed by cases. Venous blood samples were drawn from participants and used for estimating full blood count and renal function (serum creatinine (CRE), blood-urea nitrogen (BUN), BUN : CRE ratio, and estimated GFR (eGFR)). Serum lead, arsenic, and cadmium levels were estimated using the Varian AA 240FS atomic spectrometer in an acetylene-air flame.

Results

The median RBC (4.49 vs. 4.92 × 10¹²/L), haemoglobin (12.50 vs. 13.70 g/dL), and platelet (220.00 vs. 268.00) counts were significantly lower in cases. A significantly higher proportion of cases were classified as anaemic or having microcytic cells compared to controls. Also, serum urea (4.08 vs. 3.41; p=0.0009), creatinine (108.10 vs. 101.10; p=0.0286), and BUN : CRE ratio (19.75 vs. 17.84) were significantly higher in cases. Additionally, 18.1% of cases were classified as having moderately reduced renal function compared to only 6.6% of controls. Moreover, a significantly higher proportion of cases had detectable serum lead (55.6% vs. 16.4%) and arsenic (53.1% vs. 9.8%) levels compared to controls. However, on average, 80% of agricultural workers did not use personal protective equipment (PPE) when applying agrochemicals; 84.3% of used agrochemical containments were discarded near the river/canal.

Conclusion

Neglect of the use of PPE may be predisposing the agrochemical workers and community to lead and arsenic bioaccumulation with a consequent reduced haematological and renal function.

Biochemical and genotoxic effects in women exposed to pesticides in Southern Ecuador

Toxicity refers to the potential of a substance such as a pesticide to cause damage to the structure or functions of an exposed organism. Pesticides can lead to harmful biological effects in exposed animals and their offspring over the medium and long term. They can affect the immunological, nervous, endocrine, and reproductive systems. DNA damage has also been linked to exposure to pesticides, and this damage can cause abortions, degenerative diseases, and cancer. The aim of this work was to establish whether women who are indirectly exposed to pesticides exhibit a compromised health status, including genotoxic effect. Women exposed indirectly to pesticides in Chimchanga and Colaisaca in the south of Ecuador underwent hematological and biochemical tests and micronucleus assay in buccal cells. The subjects were also genotyped for GSTM1, GSTT1, GSTP1, and PON1 polymorphisms, which can modify an individual's capacity to metabolize pesticides and relation with damage of DNA. The study revealed hepatic toxicity in Colaisaca women (AST and ALT) and an increase in the rate of micronucleus (MN) in Colaisaca individuals. In addition, genetic polymorphisms in PON1 and GSTP1 showed effects of modulating the frequency of karyolytic cells, karyorrhectic cells, and condensed chromatin cells.

Migrant Farmworkers' Exposure to Pesticides in Sonora, Mexico

Expanding agribusiness in Sonora, a state in Northern Mexico, has increased the demand for temporary migrant agricultural workers. Sonora is one of the top states in Mexico for pesticide utilization. We conducted an exploratory study to evaluate exposure to organophosphate (OP) and pyrethroid pesticides among migrant farmworkers. A sample of 20 migrant farmworkers was recruited from a large commercial grape farm during the harvest season. We administered a questionnaire on work activities, exposure characteristics, and socio-demographics. We collected urine samples to quantify pesticide metabolite concentrations. Most participants were originally from the state of Chiapas, Mexico, none had completed high school, and about half spoke an indigenous language as well as Spanish. The majority of participants had detectable concentrations of pyrethroid and organophosphate biomarkers. Geometric mean creatinine-adjusted concentrations for 3-phenoxybenzoic acid (1.83 µg/g), trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid (0.88 µg/g), 4-fluoro-3-phenoxybenzoic acid (0.94 µg/g), 3,5,6-trichloro-2-pyridinol (3.56 µg/g), and para-nitrophenol (0.63 µg/g) were significantly higher than in the general United States' population and Mexican Americans. Our results also suggest that migrant farmworkers in this region are exposed to pesticides at higher levels than other farmworkers' studies. Farmworkers' age, language, training on personal protective equipment, time at the farm, and season, were significant exposure determinants.

Evidence of risks of renal function reduction due to occupational exposure to agrochemicals: A systematic review

Agriculture accountsfor an important economic activity worldwide and the search for the increased productivity incorporated the use of pesticides in this practice. Such compounds have significant environmental and human health effects, especially for workers exposed to them. Among the main health problems caused by pesticides are the renal alterations, which in more advanced stages comprise an important public health problem. For this reason, this systematic review aimed at gathering evidence of the risk of renal changes induced by occupational exposure to pesticides. The search was made in PubMed, Scopus, Lilacs and Scielo in December 2017, using keywords as pesticides, poisoning, kidney, renal insufficiency. After the application of inclusion criteria, 11 studies were selected. It was possible to gather evidence on the prevalence and risk (3.12-6.71) of renal injury from the occupational exposure of agricultural workers and its association with the exposure to agrichemicals, as organophosphates and herbicides.

Neurochemical and Behavioral Dysfunctions in Pesticide Exposed Farm Workers: A Clinical Outcome

The problem of pesticides is not new and its exposure to human due to indiscriminate use is largely associated with the health related problems including neurotoxicological alterations. High levels of pesticide residues and their metabolites in the dietary constituents, food materials, maternal blood, cord blood, placenta breast milk have been reported and linked to alterations in birth weight, crown heel length, head circumference, mid-arm circumference and ponderal index of the neonates. Epidemiological studies have suggested that exposure of pesticide to human could be a significant risk factor for neurological disorders, including Parkinson's disease, Alzheimer's disease and multiple sclerosis. Cholinergic and non-cholinergic dysfunctions in pesticide exposed population, especially in children have also been frequently reported in recent years. Developmental neurotoxicity is another concern in the area where pregnant are more prone towards its exposure and which results in the abnormalities in the fetus. In view of the increasing risk of human health through pesticide exposure, the present review has been focused on the studies pertaining to pesticide induced neurochemical alterations and associated behavioral abnormalities in farm workers which could establish a possible link between the its exposure and associated health hazards.

Evaluation of hematological and biochemical parameters of pesticide retailers following occupational exposure to a mixture of pesticides

AIMS

This study was undertaken to ascertain whether light occupational exposure to pesticides by retailers might be associated with any liver, kidney, nervous system dysfunction or hematological abnormalities.

MAIN METHODS

In this cross-sectional study, 70 male pesticide retailers (cases) and 64 male subjects, randomly selected from the constructions workers of city council contractors, as the referent group, were investigated. Urine and blood samples were taken from all subjects for urine analysis, hematological and biochemical parameters. Data analysis was conducted through SPSS v.19 using t-test and chi-square test.

KEY FINDINGS

The results of urine analysis showed that the frequency of abnormal urine tests was significantly higher in cases than in referent individuals. Similarly, the results of CBC showed that the mean values of monocyte, hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin and platelet distribution width were significantly lower, and mean corpuscular hemoglobin concentration and red blood cell distribution width were significantly higher in retailers. No significant differences were found for other parameters.

SIGNIFICANCE

These findings indicate that an association exists between exposure to pesticides by retailers and early subtle and sub-clinical changes in the urine tests and hematological parameters. Engineering measures are recommended to eliminate exposure to pesticides and to prevent its associated outcomes.

DNA damage and circulating cell free DNA in greenhouse workers exposed to pesticides

Pesticides widely used in agriculture and other applications have been linked to cancer and other diseases through several potential mechanisms. The goals of this study were to assess DNA damage in lymphocytes by the cytokinesis-block micronucleus assay (CBMN), and to measure circulating cell free DNA (ccf-DNA) in the blood of pesticide-exposed greenhouse workers and matched controls living in the same area. CBMN was applied to peripheral blood lymphocyte samples taken at different times (spring and autumn) for each individual. We measured plasma ccf-DNA levels using a Qubit^® fluorometer. The results indicated that the MNL, BNMN, and NBUDs frequencies of pesticide-exposed individuals were significantly higher than non-exposed individuals. Apart from MNL, BNMN and CBPI, a season-related effect was found for the NPB and NBUD frequencies. With MNL and BNMN as the dependent variables, multiple regression analysis showed that age and gender affected MN formation. The ccf-DNA level in the pesticide-exposed group was significantly higher than the control group. There was no seasonal variation regarding the free DNA amount. Ccf-DNA in males was found to be higher than females. The MNL, BNMN, NPB, and CBPI did not correlate with the ccf-DNA amount. It can be concluded that pesticide exposure can modulate DNA integrity via different mechanisms. Also, elevated levels of ccf-DNA could be recommended as a biomarker of pesticide exposure. Environ. Mol. Mutagen. 59:161-169, 2018. © 2017 Wiley Periodicals, Inc.

Hematological Abnormality, Oxidative Stress, and Genotoxicity Induction in the Greenhouse Pesticide Sprayers; Investigating the Role of NQO1 Gene Polymorphism

The widespread use of pesticides in agriculture represents a threat to the human populations exposed to them. In this cross-sectional study, the hematological and biochemical parameters, plasma cholinesterase (PChE) activity, oxidative stress, genotoxicity, and NAD(P)H: quinone oxidoreductase 1 (NQO1) C609T polymorphism were measured in 100 greenhouse workers occupationally exposed to pesticide mixture and 104 normal healthy controls. There was a decrease in erythrocytes (5.45%, p = 0.026) and hemoglobin (3.26%, p = 0.025), and an increase in mean corpuscular hemoglobin (3.54%, p = 0.013) in the exposed workers. Sprayers showed a reduction in PChE (23%) and GSH (50%) levels, and an increase in lipid peroxidation (LPO) (55%), protein carbonyl (145%), Superoxide dismutase activity (61%), and total antioxidant capacity (35%) (p < 0.001 for all parameters but LPO: p = 0.009). Genotoxicity parameters were significantly high in the exposed cases (for all parameters: p < 0.001 but tail length: p = 0.002). There was a significant correlation between oxidative stress and genotoxicity parameters, and also between these biomarkers and PChE activity. The NQO1 C609T polymorphism was not significantly associated with studied biomarkers. The findings indicate that occupational exposure to a mixture of pesticides can induce hematotoxicity, oxidative stress, and genotoxicity in greenhouse workers.

Renal damage induced by the pesticide methyl parathion in male Wistar rats

Little information is apparently available regarding the nephrotoxic effects induced by pesticides. The aim of this study was to examine the influence of low doses of methyl parathion (MP) on the structure and function of the kidney of male Wistar rats. A corn oil (vehicle) was administered to control rats, whereas treated rats received MP at 0.56 mg/kg orally (1/25 of LD₅₀), every third day, for 8 weeks. At the end of each week following MP exposure, creatinine and glucose levels were measured in plasma, while glucose, inorganic phosphate, total proteins, albumin, and activity of γ-glutamyltranspeptidase (GGT) were determined in urine. Kidney histological study was also performed. Compared with control rats, MP significantly increased plasma glucose and creatinine levels accompanied by decreased urinary flow rate and elevated urinary excretion rates of glucose, phosphate, and albumin. Further, the activity of GGT in urine was increased significantly. The proximal cells exhibited cytoplasmic vacuolization, positive periodic acid Schiff inclusions, and brush border edge loss after 2 or 4 weeks following MP treatment. Finally, renal cortex samples were obtained at 2, 4, 6, and 8 weeks of MP treatment, and the concentrations of reduced glutathione (GSH) and glutathione peroxidase (GPx) activity were measured. The mRNA expression levels of BAX and tumor necrosis factor-α (TNF-α) were also determined (RT-PCR). MP significantly decreased renal GSH levels, increased GPx activity, as well as downregulated the mRNA expression of TNF-α and BAX. Densitometry analysis showed a significant reduction in TNF-α and BAX mRNA expression levels at 2 and 4 weeks following MP treatment. Low doses of MP produced structural and functional damage to the proximal tubules of male rat kidney.

Molecular detection of M. tuberculosis and M. bovis and hematological and biochemical analyses in agricultural sprayers exposed to pesticides: A cross-sectional study in Punjab, Pakistan during 2014-2016

We determined the correlation between a pesticide exposure, physical health and susceptibility toward tuberculosis along with hematological indices and liver enzymes' alterations in sprayers exposed to pesticides. Molecular detection of Mycobacterium tuberculosis and Mycobacterium bovis was detected by targeting histone-like protein (hupB) gene. The WBC (white blood cells) and RBC (red blood cells) levels of male sprayers and non-sprayers were significantly different (P<0.05). In female spray workers, the WBC and neutrophils levels were significantly different as compared with non-sprayers. Overall, in both male and female pesticide-exposed sprayers, mean values of alanine amino transferase and aspartate amino transferase were higher as compared with unexposed workers. M. Tuberculosis were detected in 15% male sprayers and 36% female sprayers while, M. bovis was detected in 5% male sprayers and 10% female sprayers. A χ²-test indicated that there existed a significant different (P<0.05) between positive and negative M. tuberculosis and M. bovis in both male/female spray workers out of total. The susceptibility of pesticide-exposed sprayers to tuberculosis and alterations in hematology and liver enzymes is crucial for health. Toxic effects of pesticides may lead to a weak immune system and increased tuberculosis susceptibility.

Pesticide exposures and chronic kidney disease of unknown etiology: an epidemiologic review

The main causes of chronic kidney disease (CKD) globally are diabetes and hypertension but epidemics of chronic kidney disease of unknown etiology (CKDu) occur in Central America, Sri Lanka, India and beyond. Althoug also being observed in women, CKDu concentrates among men in agricultural sectors. Therefore, suspicions fell initially on pesticide exposure, but currently chronic heat stress and dehydration are considered key etiologic factors. Responding to persistent community and scientific concerns about the role of pesticides, we performed a systematic review of epidemiologic studies that addressed associations between any indicator of pesticide exposure and any outcome measure of CKD. Of the 21 analytical studies we identified, seven were categorized as with low, ten with medium and four with relatively high explanation value. Thirteen (62%) studies reported one or more positive associations, but four had a low explanation value and three presented equivocal results. The main limitations of both positive and negative studies were unspecific and unquantified exposure measurement ('pesticides'), the cross-sectional nature of most studies, confounding and selection bias. The four studies with stronger designs and better exposure assessment (from Sri Lanka, India and USA) all showed exposure-responses or clear associations, but for different pesticides in each study, and three of these studies were conducted in areas without CKDu epidemics. No study investigated interactions between pesticides and other concommittant exposures in agricultural occupations, in particular heat stress and dehydration. In conclusion, existing studies provide scarce evidence for an association between pesticides and regional CKDu epidemics but, given the poor pesticide exposure assessment in the majority, a role of nephrotoxic agrochemicals cannot be conclusively discarded. Future research should procure assessment of lifetime exposures to relevant specific pesticides and enough power to look into interactions with other major risk factors, in particular heat stress.

Drug Hepatotoxicity: Environmental Factors

Drug-induced liver injury presents as various forms of acute and chronic liver disease. There is wide geographic variation in the most commonly implicated agents. Smoking can induce cytochrome P450 enzymes but this does not necessarily translate into clinically relevant drug-induced liver injury. Excessive alcohol consumption is a clear risk factor for intrinsic hepatotoxicity from acetaminophen and may predispose to injury from antituberculosis medications. Understanding of the role of infection, proinflammatory states, disorders of coagulation, and the hepatic clock in predisposing patients to drug-induced liver injury is evolving. More study focusing specifically on environmental risk factors predisposing patients to drug-induced liver injury is needed.

Hispanic health in the USA: a scoping review of the literature

Hispanics are the largest minority group in the USA. They contribute to the economy, cultural diversity, and health of the nation. Assessing their health status and health needs is key to inform health policy formulation and program implementation. To this end, we conducted a scoping review of the literature and national statistics on Hispanic health in the USA using a modified social-ecological framework that includes social determinants of health, health disparities, risk factors, and health services, as they shape the leading causes of morbidity and mortality. These social, environmental, and biological forces have modified the epidemiologic profile of Hispanics in the USA, with cancer being the leading cause of mortality, followed by cardiovascular diseases and unintentional injuries. Implementation of the Affordable Care Act has resulted in improved access to health services for Hispanics, but challenges remain due to limited cultural sensitivity, health literacy, and a shortage of Hispanic health care providers. Acculturation barriers and underinsured or uninsured status remain as major obstacles to health care access. Advantageous health outcomes from the "Hispanic Mortality Paradox" and the "Latina Birth Outcomes Paradox" persist, but health gains may be offset in the future by increasing rates of obesity and diabetes. Recommendations focus on the adoption of the Health in All Policies framework, expanding access to health care, developing cultural sensitivity in the health care workforce, and generating and disseminating research findings on Hispanic health.

Association of Long-Term Pesticide Exposure and Biologic Parameters in Female Farm Workers in Tanzania: A Cross Sectional Study

The study aimed to assess the association of long-term pesticide exposure (≥5 years) with hematological, serum biochemical parameters and acetylcholinesterase activity in farm workers. These pesticides included organophosphorus pesticides, carbamates, pyrethroids, dithiocarbamates, and other pesticides such as endosulfan. Applying a cross-sectional study design, 69 females from a pesticide-exposed farm population and 30 females from a district not using pesticides (reference group) were studied. The mean red cell corpuscular volume and hematocrit values were significantly lower (74.7 ± 9.1 fl; 95% CI 72.5-76.9 and 32.0% ± 4.6%; 95% CI 30.9-33.1, respectively) in the exposed compared to the reference group, whereas mean corpuscular hemoglobin concentration and platelets were significantly higher (37.4 ± 3.8 g/dL; 95% CI 36.5-38.3 and 374.1 ± 95.3/L; 95% CI 351.2-396.9, respectively) in the exposed compared to the reference group. Mean serum glutamic oxaloacetate transaminase (20.7 ± 8.9 U/L; 95% CI 18.5-22.9) and creatinine (83.9 ± 6.6 μmol/L; 95% CI 82.3-85.5) were significantly higher in the exposed compared to the reference group. A higher mean esterase activity (AChE 0.6 ± 0.2 mM/min/mg protein; 95% CI 0.56-0.7; BChE 0.9 ± 0.4 mM/min/mg protein; 95% CI 0.9-1.1) was noted in the exposed group. Regression models suggest that occupational exposure (p < 0.001) could be a predictor of esterase (AChE and BChE) activity and biochemical changes (β = 0.4, 95% CI: 0.3-0.5; β = 0.7, 95% CI: 0.6-0.9, respectively). Long-term pesticide exposure affects the hemato-biochemical and esterase responses, establishing the need for further studies.

Modulatory role of GSTM1 null genotype on the frequency of micronuclei in pesticide-exposed agricultural workers

In this study, we aimed to investigate the extent of genotoxic risk and the association between null GSTM1/GSTT1 and GSTP1 Ile105Val variants and cellular DNA damage, as measured by micronucleus (MN) assay in a group of agricultural workers from Denizli, Turkey. Peripheral blood samples were collected from 116 subjects, including 58 workers who were occupationally exposed to pesticides and 58 healthy unexposed controls. The MN frequencies of each individual were assessed by cytokinesis-blocked micronuclei assays on lymphocytes. Genotypes for different GST variants were determined using polymerase chain reaction-based methods. A significant 3.4-fold increase in MN frequency was observed in workers compared with the controls ( p < 0.001). Among the GST genotypes, only the GSTM1 null genotype was found to be significantly associated with an increased MN frequency in workers ( p = 0.01). Individuals with a concomitant null GSTM1/GSTT1 genotype demonstrated a significant ( p = 0.01) increase in MN frequency compared with those with functional isozymes in the exposed worker group. The association of the GSTM1 null genotype with higher MN frequency suggests that it may be a modifier of genotoxic risk in individuals exposed to pesticides and may thus be a candidate susceptibility biomarker for human biomonitoring studies.

Association between pesticide exposure and risk of kidney cancer: a meta-analysis

This meta-analysis aimed to evaluate the correlation between pesticide exposure and kidney cancer. We conducted a systematic search of the Cochrane Library, Embase, Web of Knowledge, and Medline (updated to March 1, 2015) to identify all relevant studies. References of the retrieved articles were also identified. Fixed- or random-effect models were used to summarize the estimates of relative risk (RR) with 95% confidence interval for the association between exposure of pesticide and risk of kidney cancer. The pooled RR estimate indicated that pesticide exposure might have an elevated risk for kidney cancer (RR =1.10, 95% confidence interval 1.01–1.19). In a subgroup analysis of high quality articles, we detected that pesticide exposure is a significant risk factor for kidney cancer in a subgroup analysis of case-control studies, (Newcastle–Ottawa Quality Assessment Scale score >6) (RR =1.31, 95% confidence interval 1.12–1.51). North America studies, odds ratio studies, and studies with effect estimate adjusted for more than two confounder studies. In conclusion, pesticide exposure may be a risk factor for kidney cancer.

Environmental exposure to pesticides and respiratory health

Respiratory effects of environmental exposure to pesticides are debated. Here we aimed to review epidemiological studies published up until 2013, using the PubMed database. 20 studies dealing with respiratory health and non-occupational pesticide exposure were identified, 14 carried out on children and six on adults. In four out of nine studies in children with biological measurements, mothers' dichlorodiphenyldichloroethylene (DDE) blood levels during pregnancy were associated with asthma and wheezing in young children. An association was also found between permethrin in indoor air during pregnancy and wheezing in children. A significant association between asthma and DDE measured in children's blood (aged 7-10 years) was observed in one study. However, in three studies, no association was found between asthma or respiratory infections in children and pesticide levels in breast milk and/or infant blood. Lastly, in three out of four studies where post-natal pesticide exposure of children was assessed by parental questionnaire an association with respiratory symptoms was found. Results of the fewer studies on pesticide environmental exposure and respiratory health of adults were much less conclusive: indeed, the associations observed were weak and often not significant. In conclusion, further studies are needed to confirm whether there is a respiratory risk associated with environmental exposure to pesticides.

Occupational exposure to pesticides and respiratory health

This article aims to review the available literature regarding the link between occupational exposure to pesticides and respiratory symptoms or diseases. Identification of epidemiological studies was performed using PubMed. 41 articles were included, 36 regarding agricultural workers and five regarding industry workers. Among the 15 cross-sectional studies focusing on respiratory symptoms and agricultural pesticide exposure, 12 found significant associations with chronic cough, wheeze, dyspnoea, breathlessness or chest tightness. All four studies on asthma found a relationship with occupational exposure, as did all three studies on chronic bronchitis. The four studies that performed spirometry reported impaired respiratory function linked to pesticide exposure, suggestive of either obstructive or restrictive syndrome according to the chemical class of pesticide. 12 papers reported results from cohort studies. Three out of nine found a significant relationship with increased risk of wheeze, five out of nine with asthma and three out of three with chronic bronchitis. In workers employed in pesticide production, elevated risks of chronic obstructive pulmonary disease (two studies out of three) and impaired respiratory function suggestive of an obstructive syndrome (two studies out of two) were reported. In conclusion, this article suggests that occupational exposure to pesticides is associated with an increased risk of respiratory symptoms, asthma and chronic bronchitis, but the causal relationship is still under debate.

The 28-day exposure to fenpropathrin decreases locomotor activity and reduces activity of antioxidant enzymes in mice brains

BACKGROUND

Fenpropathrin (Fen) is a pyrethroid (Pyr) insecticide. Pyrs are used in veterinary medicine, in agriculture and for domestic purposes. As their use increases, new questions about their side effects and mode of action in non-target organisms arise. The objective of this work was to characterize dose-response relationship for in vivo motor function and memory in mice exposed to Fen for 28 days and to assess its influence on activity of antioxidant enzymes in mice brains.

METHODS

The experiment was performed using 64 female mice. Fen at the dose of 11.9mg/kg of body mass, 5.95mg/kg or 2.38mg/kg was administered ip to the mice for 28 consecutive days. Motor function and spatial working memory were tested on days 7, 14 and 28. On day 29, the animals were sacrificed and brains were used to determine activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx).

RESULTS

Fen significantly decreased locomotor activity in mice receiving the highest dose at every stage of the experiment. Lower doses reduced locomotion on days 7 and 14. Fen did not produce memory impairment. A decrease in activities of SOD and GPx was recorded in mice brains.

CONCLUSIONS

The decrease of SOD activity in mice brains results from direct inhibition of the enzyme by Fen and/or increased utilization due to excessive free radical formation in conditions of Fen-induced oxidative stress. The reduction in GPx activity is probably due to limited glutathione availability. The reduced locomotor activity is a behavioral demonstration of Fen-induced damage in the dopaminergic system.

Pesticide use and risk of end-stage renal disease among licensed pesticide applicators in the Agricultural Health Study

OBJECTIVES

Experimental studies suggest a relationship between pesticide exposure and renal impairment, but epidemiological evidence is limited. We evaluated the association between exposure to 39 specific pesticides and end-stage renal disease (ESRD) incidence in the Agricultural Health Study, a prospective cohort study of licensed pesticide applicators in Iowa and North Carolina.

METHODS

Via linkage to the US Renal Data System, we identified 320 ESRD cases diagnosed between enrolment (1993-1997) and December 2011 among 55 580 male licensed pesticide applicators. Participants provided information on use of pesticides via self-administered questionnaires. Lifetime pesticide use was defined as the product of duration and frequency of use and then modified by an intensity factor to account for differences in pesticide application practices. Cox proportional hazards models, adjusted for age and state, were used to estimate associations between ESRD and: (1) ordinal categories of intensity-weighted lifetime use of 39 pesticides, (2) poisoning and high-level pesticide exposures and (3) pesticide exposure resulting in a medical visit or hospitalisation.

RESULTS

Positive exposure-response trends were observed for the herbicides alachlor, atrazine, metolachlor, paraquat, and pendimethalin, and the insecticide permethrin. More than one medical visit due to pesticide use (HR=2.13; 95% CI 1.17 to 3.89) and hospitalisation due to pesticide use (HR=3.05; 95% CI 1.67 to 5.58) were significantly associated with ESRD.

CONCLUSIONS

Our findings support an association between ESRD and chronic exposure to specific pesticides, and suggest pesticide exposures resulting in medical visits may increase the risk of ESRD.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov NCT00352924.

Long- and short-term health effects of pesticide exposure: a cohort study from China

Pesticides are extensively used by farmers in China. However, the effects of pesticides on farmers’ health have not yet been systematically studied. This study evaluated the effects of pesticides exposure on hematological and neurological indicators over 3 years and 10 days respectively. A cohort of 246 farmers was randomly selected from 3 provinces (Guangdong, Jiangxi, and Hebei) in China. Two rounds of health investigations, including blood tests and neurological examinations, were conducted by medical doctors before and after the crop season in 2012. The data on pesticide use in 2009–2011 were collected retrospectively via face-to-face interviews and the 2012 data were collected from personal records maintained by participants prospectively. Ordinary least square (OLS), Probit, and fixed effect models were used to evaluate the relationship between pesticides exposure frequency and the health indicators. Long-term pesticide exposure was found to be associated with increased abnormality of nerve conductions, especially in sensory nerves. It also affected a wide spectrum of health indicators based on blood tests and decreased the tibial nerve compound muscle action potential amplitudes. Short-term health effects included alterations in complete blood count, hepatic and renal functions, and nerve conduction velocities and amplitudes. However, these effects could not be detected after 3 days following pesticide exposure. Overall, our results demonstrate that pesticide exposure adversely affects blood cells, the liver, and the peripheral nervous system. Future studies are needed to elucidate the specific effects of each pesticide and the mechanisms of these effects.

Characterization of risk factors for DNA damage among paddy farm worker exposed to mixtures of organophosphates

This is a cross-sectional study conducted among paddy farmers to characterize potential risk factors that influence levels of DNA damage from exposure to mixtures of organophosphates. Comet assay was used to determine the level of DNA damage by measuring the comet tail length from the exfoliated buccal mucosa. The result suggests that farmers who chronically exposure to a mixture of organophosphates has at least 2-fold significant increase of DNA damage as compared with control group. Factor analysis and linear regression both suggest that DNA damage reported by farmers may influence individual, occupational, and residential factors and are reported as significant predictor factors, whereas this effect is mainly caused by individual factors among the control group. The findings of the present study suggest that either farmer or control group bear certain extent of genotoxic burden contributed by different risk factors.

Subacute poisoning of mice with deltamethrin produces memory impairment, reduced locomotor activity, liver damage and changes in blood morphology in the mechanism of oxidative stress

BACKGROUND

Deltamethrin (DEL) is a synthetic pyrethroid (PYR) insecticide, potent neurotoxicant. The current investigation was envisaged to explore behavioral, biochemical and morphologic effects of subacute poisoning with DEL in mice and to find one common mechanism of these changes.

METHODS

Mice were daily injected ip with different doses of DEL: 8.3, 20.75 or 41.5mg/kg bw for 28 days. Their memory retention in passive avoidance task (PA), fresh spatial memory in a Y-maze and locomotor activity were measured once weekly. On day 29, blood morphology, alanine transaminase (ALT) activity and creatinine concentration in the blood sera, superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities were measured in the livers and kidneys. Livers were examined with light microscopy.

RESULTS

Significant impairment of memory retention was recorded on day 2, 7 and 28 after exposure to DEL. Fresh spatial memory was significantly impaired by the highest dose of DEL on day 1, 14 and 28. Locomotor activity was reduced at every stage of experiment in all the groups exposed to DEL. In the animals exposed to the highest dose of DEL activities of alanine transaminase (ALT) and SOD were elevated, GPx was reduced, lymphocyte infiltrates were detected in the livers and there were changes in blood morphology.

CONCLUSION

The results obtained indicate that liver and bone marrow, apart from the central nervous system (CNS) are damaged in the course of subacute poisoning with DEL. The possible common mechanism of the damage is oxidative stress.

Lifetime and current pesticide exposure among Latino farmworkers in comparison to other Latino immigrants

BACKGROUND

Pesticide exposure poses a health risk for farmworkers. This analysis documents lifetime and current pesticide exposure of North Carolina Latino migrant farmworkers, with comparison to non-farmworker Latino immigrants.

METHODS

During May to October 2012, 235 Latino farmworkers and 212 Latino non-farmworkers completed interviews with items to construct measures of lifetime, current residential and occupational pesticide exposure.

RESULTS

Farmworkers experience levels of lifetime and residential pesticide exposure that are consistently greater than among non-farmworkers. Farmworkers report a large number of occupational pesticide exposures. Lifetime exposure and current residential pesticide exposure are related to social determinants. Education is inversely related to lifetime pesticide exposure for farmworkers and non-farmworkers; farmworkers with H-2A visas report greater residential pesticide exposure than those without H-2A visas.

CONCLUSIONS

Occupational safety policy needs to consider these patterns of lifetime exposure when setting standards. Health care providers should be aware of the lifetime and current exposure of this vulnerable population.

Does farming have an effect on health status? A comparison study in west Greece

Investigating the health status of agricultural workers is a challenging goal. Contradictory outcomes concerning farmers' health are reported in the literature. In this cross-sectional study, certain clinical and neurobehavioral health outcomes were compared between farmers and non-farmers living in the same rural area. Farmers (328) and non-farmers (347), matched per age and sex, were selected randomly in an agricultural area in West Greece. Both groups underwent haematological and biochemical examinations and were administered two neurobehavioral tests, namely the Mini-Mental State Examination (MMSE) and the Montgomery-Åsberg Depression Rating Scale (MADRS). Sociodemographic, personal medical, nutritional and lifestyle data were recorded. According to personal statements, farmers suffered from hypertension, cardiovascular, orthopaedic and ENT problems in higher frequency. Haematocrit, haemoglobin and serum cholinesterase's activity were found to be lower among farmers. Lower prevalence of hypertension and better performances on MMSE and MADRS tests were recorded in young farmers in relation to young non-farmers, while these findings were reversed in older ages. Odds Ratios were calculated through multivariate logistic regression models. Factors affecting these impairments remain to be clarified.

Effect of pesticide exposure on platelet indices in farm workers

We aimed to assess the effect of exposure to pesticide on platelet indices including mean platelet volume (MPV) and platelet distribution width (PDW) in farm workers. The study group consisted of 40 farm workers (4 females, 36 males; mean age 42.6 ± 9.8 years). An age-, gender- and body mass index-matched control group was composed of 38 healthy volunteers (8 females, 30 males; mean age 46.1±8.9 years). Platelet indices were assessed in farm workers exposed to pesticides. MPV values were significantly lower in farm workers than in those of controls (6.3 ± 1.1 vs. 7.6 ± 0.7 fL, respectively; p < 0.001). Platelet count was significantly lower in farm workers than those of controls (155.7 ± 35.7 vs. 271.3 ± 96.2 × 10(9)/L, respectively; p < 0.001). PDW was significantly lower in farm workers than in those of controls (8.9% ± 2.0% vs. 15.8% ± 0.8%, respectively; p < 0.001). We have found that MPV and other platelet indices were significantly lower in farm workers exposed to pesticides than those of controls. Our findings suggest that MPV may be a sensitive indicator of a pesticide-exposure effect.