Genetic Polymorphism in Xenobiotic Metabolising Genes and Increased Oxidative Stress among Pesticides Exposed Agricultural Workers Diagnosed with Cancers.

BACKGROUND: Oxidative stress combined with nullity of xenobiotic metabolizing GSTT1/GSTM1/CYP2E1 genes may increase the susceptibility of agricultural workers to adverse health effects including cancer. The present study was conducted to determine; the prevalence of polymorphisms in GSTM1, GSTT1 and CYP2E1 genes, serum 8-hydroxy-2'-deoxygunosine levels, and the role of these markers in risk of cancer among agricultural workers occupationally exposed to pesticides. METHODS: A total of 360 participants, of which 180 belonging to farming group diagnosed with leukemia (n=60), lymphoma (n=60) and breast cancers (n=60), 90 in non-farming group diagnosed with similar cancers and the other 90 as healthy controls with neither history of occupational exposure nor diagnosed with any type of cancers were recruited. Following the questionnaire survey, serum 8-OHdG and genetic polymorphisms in the three genes were determined using ELISA and PCR methods respectively. RESULTS: The results of the study revealed that farm workers carrying GSTT1 null genotype had increased risk for lymphoma (OR = 5.34; 95% CI = 1.80-15.82) and breast cancer (OR=4.04; 95% CI = 1.24-13.07). For farm workers carrying GSTM1 null genotype, the risk was six-fold for breast cancer (OR = 6.88; 95% CI =1.88-25.99). Further, there found a significant difference between 8-OHdG and nullity of CYP2E1 among the farm workers diagnosed with leukemia. CONCLUSION: The findings of the present study suggest that the polymorphisms in detoxifying genes among farm workers occupationally exposed to pesticides and the oxidative stress may likely be responsible for triggering the mechanism of malignancy.

Knowledge, attitude and practices related to pesticide usage among farmers: Findings from a hospital based cross-sectional study.

BACKGROUND: In India, where agriculture is the prime occupation among the rural population, farmers are extensively using pesticides in crop production without taking adequate precautions. OBJECTIVE: The current study aimed to examine pesticide usage patterns, usage of personal protective equipment (PPE), knowledge on pesticide toxicity, and attitude towards occupational safety among farmers diagnosed with leukaemia (n = 60), lymphoma (n = 33), and breast cancer (n = 30) visiting a tertiary cancer care hospital in Hyderabad, India. METHODS: Face-to-face interviews were conducted using a pre-tested questionnaire and the data collected were analysed with statistical software SPSS 23. RESULTS: The survey revealed that the participants had an average of 19.6 years of farming experience and women were predominantly involved in the mixing of pesticides and other agricultural work apart from spraying. All of them were not using any PPE and the majority of them did not have any knowledge on the route of exposure, toxicity symbols, and safe handling of pesticides. Statistical analysis showed no significant association between educational status and knowledge, attitude and practices (p > 0.05). CONCLUSION: Even though the majority of the farmers were educated, their lack of adequate knowledge on pesticides had enabled them to adopt risky behaviours in handling and storage of pesticides. There is a need for continuous training programs for farmers to promote awareness and minimize the hazards of occupational exposure.

The impact of the use of personal-protective-equipment on the minimization of effects of exposure to pesticides among farm-workers in India.

Introduction: Although excessive use of pesticides and unsafe agricultural practices may contribute to numerous intoxications, the role of PPE (personal-protective-equipment) in the minimization of toxicological effects due to pesticide exposure has not been addressed so far. The present study aimed to assess the impact of the use of PPE on the minimization of effects of exposure to pesticides among farm-workers. Methods: A community-based follow-up study with questionnaire-based survey and field observations was undertaken among farm-workers (n = 180) of Rangareddy district, Telangana, India. Biomarkers of exposure such as cholinesterase activity, inflammatory markers (TNF-α, IL-1ß, IL-6, cortisol, and hs-C reactive protein), nutrients (vitamins A, E), liver function (total protein and A/G ratio, AST and ALT levels) were investigated in the laboratory by following the standard protocols. Results: Farm-workers who had a mean farming exposure of 18 years of and who neither followed safe pesticide handling practices nor used PPE and also showed reluctance to obey good agricultural practices (GAPs). Inhibition of AChE (acetylcholine esterase) with increased inflammation was found among farm-workers as compared to their respective normal values when they have not used PPE. Linear regression statistical analysis revealed a profound effect on inhibition in the AChE activity and various inflammatory markers with the increase in the duration of pesticide exposure. Further, there was no effect of the duration of pesticide exposure on the levels of vitamins A, E, ALT, AST, total protein, and A/G ratio. Further, intervention studies carried out on the use of PPE provided (commercially available and cost-effective) for 90 days showed a significant reduction in the biomarker levels (p < 0.01). Conclusion: This study demonstrated the importance of the use of PPE during pesticide applications and other agricultural tasks to minimize pesticide-associated adverse health effects.

Assessment of dermal exposure to pesticides among farmers using dosimeter and hand washing methods.

Inappropriate use of pesticides followed by unsafe handling practices to control the insect infestation among the farming groups in developing countries has resulted in a high exposure risk. The use of personal protective equipment is also negligible among Indian farmers due to their affordability to access the same. Very little research has been conducted to establish an exposure assessment procedure through dermal penetration of pesticide residues. Therefore, to quantify the contamination of pesticide residues through dermal exposure along with detailed field observations and pesticide management practices, a field study was conducted in Rangareddy district, Telangana, Southern India, to assess the dermal exposure based on dosimeter and hand washing methods. The analytical method was modified and validated in-house for performance parameters such as limit of detection, quantification, linear range, recovery, and precision. The potential dermal exposure values ranged from 0.15 to 13.45 µg, while a reduction was found in exposure levels as actual dermal exposure values ranged from 0 to 0.629 µg. Contamination through hand washing was the major contributor to overall dermal exposure. Statistical analysis revealed a significant difference in the exposed dermal regions of the leg and torso after the use of PPE. Penetration factor for each anatomical region and risk evaluation in terms of the Margin of Safety implies unsafe handling of pesticides. The findings of the present study confirm the increased exposure to organophosphate pesticides among operators and highlight the importance of the use of protective measures, especially among those that focus on dermal exposure mitigation.

Impact of Micronutrient Supplementation on Pesticide Residual, Acetylcholinesterase Activity, and Oxidative Stress Among Farm Children Exposed to Pesticides.

The present interventional study aimed to assess the impact of micronutrient supplementation on pesticide-residues concentrations, vitamins, minerals, acetylcholinesterase activity and oxidative stress among 129 farm children (9-12 years, n = 66 and 13-15 years, n = 63) involved in farming activities in Ranga Reddy district, Telangana, India. Our data showed the presence of five organophosphorus pesticide residues (chlorpyrifos, diazinon, malathion, monocrotophos, and phosalone) among children before-supplementation (both age-groups); while post-supplementation, only two pesticide residues (chlorpyrifos and diazinon) were detected indicating improved metabolic rate. Vitamin E, copper, magnesium and zinc levels were also improved in both the age-groups and manganese levels were significantly increased only among children of 13-15 years age group. Further, post-supplementation also showed an improvement in acetylcholinesterase activity and a decrease in lipid peroxidation among both the age groups of children. However, further research for ascertaining the ameliorating effect of micronutrients in preventing adverse effects of organophosphorus pesticides must be conducted.

Alterations in reproductive hormone levels among farm women and their children occupationally exposed to organophosphate pesticides.

Exposure to organophosphorus pesticides may lead to reproductive hormone dysfunction. Even among children of pubertal age, the exposure may disrupt growth, development, and maturation. The present study was conducted to assess the alterations in the reproductive hormone levels, among farm women (24-45 years, n = 129) and their children (9-12 years, n = 66 and 13-15 years, n = 63) and compare them with age and gender-matched control group [women (n = 134) and their children (9-12 years, n = 69 and 13-15 years, n = 65)] belonging to villages of Ranga Reddy District, Telangana, India. Blood pesticide residues and reproductive hormone (follicle-stimulating hormone-FSH, luteinizing hormone-LH, estradiol, and testosterone) levels were analyzed. The detected pesticide residues (ng/mL) were chlorpyrifos, diazinon, malathion, and monocrotophos among the farm women, while the farm children of 9-12 years age groups were detected with residues of chlorpyrifos, diazinon, malathion, monocrotophos, and phosalone. The farm children of 13-15 years age group were detected with residues of chlorpyrifos, diazinon, malathion, monocrotophos, and phosalone. However, no residues were detected among the samples of women and children of control groups. Significantly lower levels of FSH (in follicular phase) were observed among the farm women than the control group. Significant alterations in FSH and LH levels of farm women were observed with a significant correlation between the chlorpyrifos residue levels and estradiol hormone. While no such significant change in hormone levels was observed among the farm children of both age groups of both genders. Though the present study showed pesticide-induced alterations in hormone levels among the farm women, research is needed to elucidate the critical windows during which exposure may adversely affect the reproductive system in children at the pubertal stage and women at reproductive age and subsequently their progeny's health at a later stage of life.

Effect of organophosphorus pesticide exposure on the immune cell phenotypes among farm women and their children.

Epidemiological studies suggest suppression of the lymphocytes function through cholinergic stimulation due to organophosphorus pesticide exposure. The study aimed to assess the alteration in the levels of immune cell phenotypes among farm women (FW) and farm children (FC) who were occupationally exposed to pesticides and age/gender-matched control subjects belonging to Rangareddy district (Telangana, India). A total of 129 FW, 129 FC and 268 age/gender-matched controls were recruited. Blood samples were collected from the selected subjects to estimate the levels of nine organophosphorus pesticide residues and CD (CD3+, CD4+, CD8+, CD16+ and CD19+) cell markers using LC-MS/MS and flow cytometry, respectively. Independent t-test analysis was conducted to compare the immune cell phenotypes between exposed and control groups. Spearman's rank correlation test was further carried out to identify any possible correlation between the pesticide residues and CD markers. The mean percentage for CD4+, CD8+ and CD16+ was found to be significantly low, while for CD19 + itwas significantly high in the FW as compared to the CW group (p < 0.01). Further, the residues of chlorpyrifos and monocrotophos among FW were found to be significantly correlating with the mean percentages of CD19+ and CD8+ markers, respectively. The cell marker subsets of CD4+ and CD8+ were significantly low in FC children 9-12 years and 13-15 years age groups, respectively (p < 0.05). Also, these levels were significantly correlating with the residues of malathion and monocrotophos. The present study could indicate an alteration in the lymphocytes' subpopulations, which may thereby infer the toxicity in the first phase assessment of immunotoxicity. Therefore, further studies may be conducted to understand the suspected pesticides' mechanism along with various other factors in causing immune suppression coupled with nutritional and other related disorders.

Organophosphate pesticide exposure among farm women and children: Status of micronutrients, acetylcholinesterase activity, and oxidative stress.

Nutritional status plays a major role in determining the possible adverse health outcomes due to pesticide toxicity. The objective of the present study was to assess the organophosphorus pesticide residue levels among farm women (FW) (24-45years) and farm children (FC) (9-12 and 13-15years) belonging to the Rangareddy district (Telangana, India) along with their micronutrient status, inhibition of acetylcholinesterase activity, and oxidative stress levels. Residues of Chlorpyrifos, Diazinon, Malathion, Monocrotophos and Phosalone were found in the serum samples of FW and FC along with significantly low levels of vitamins and minerals. Inhibition of AChE activity was observed in FW and FC and altered oxidative stress parameters among FW. Correlation studies have found significant associations between the pesticide residues, micronutrients and antioxidant enzymes. The study suggests an association between pesticide exposure coupled with micronutrient deficiency, induced AChE inhibition, and oxidative stress.

Predominant role of antioxidants in ameliorating the oxidative stress induced by pesticides.

Oxidative stress has been reported as one of the adverse effects caused due to pesticides, which is the main mechanism of the toxicity in humans and animals and is a useful parameter in monitoring studies. It involves an imbalance in the equilibrium state of ROS and antioxidant defenses leading to alterations in various antioxidant enzyme levels and lipid peroxidation. The objective of the current paper is to present a review of the potential role and protective mechanism action of the antioxidant micronutrient supplementation to ameliorate the oxidative stress induced by pesticides. Studies in animal models and human were retrieved through the relevant search of the literature and categorized. Various animal studies were categorized according to the type of supplementation. Animal studies provide evidence to conclude the potential protective role of antioxidants in ameliorating the adverse effects of pesticides. Similar studies in humans are meager suggesting for further comprehensive research.

An improved dispersive solid-phase extraction clean-up method for the gas chromatography-negative chemical ionisation tandem mass spectrometric determination of multiclass pesticide residues in edible oils.

An improved sample preparation using dispersive solid-phase extraction clean-up was proposed for the trace level determination of 35 multiclass pesticide residues (organochlorine, organophosphorus and synthetic pyrethroids) in edible oils. Quantification of the analytes was carried out by gas chromatography-mass spectrometry in negative chemical ionisation mode (GC-NCI-MS/MS). The limit of detection and limit of quantification of residues were in the range of 0.01-1ng/g and 0.05-2ng/g, respectively. The analytes showed recoveries between 62% and 110%, and the matrix effect was observed to be less than 25% for most of the pesticides. Crude edible oil samples showed endosulfan isomers, p,p'-DDD, α-cypermethrin, chlorpyrifos, and diazinon residues in the range of 0.56-2.14ng/g. However, no pesticide residues in the detection range of the method were observed in refined oils.

Effect of background derivatization on the signal enhancement of pesticide residues extracted from edible oils.

The effect of background derivatization on the signal enhancement of pesticide residues extracted from edible oil samples was studied by GC with negative chemical ionization MS. The analytes were extracted by a solvent extraction process, and the extract was subjected to rapid low-temperature fat precipitation. The residual fatty acids were silylated by derivatization with N,O-bis(trimethylsilyl)trifluoroacetamide. The chromatograms obtained from the derivatized samples showed higher signal intensity and lower detection levels when compared to the direct analysis without derivatization. The sensitivity levels of the method are either better or comparable to that of previously reported methodologies. The LODs of the analyzed organochlorine, organophosphorus, and synthetic pyrethroid residues in sunflower, rice bran, and ground oil samples were in the range of 0.02­0.5 ng/g, and the LOQs were in the range of 0.1­2 ng/g. The intraday and interday accuracies were in the range of 81­116% with RSDs less than 14%. The recoveries obtained were in the range of 53­89% with the RSD values less than 13% for all the studied pesticide residues.

Genotoxicity in agricultural farmers from Guntur district of South India--A case study.

BACKGROUND: Pesticides play an important role in controlling the pests on agricultural crops and thereby to increase the yield of agricultural produce. Farmers occupationally exposed to pesticides during spraying activities are more prone to genotoxicity than unexposed. AIM: To assess the genotoxicity in farmers, engaged in spraying complex mixture of pesticides in the cultivation of cotton crops. MATERIAL AND METHODS: A total number of 152 male subjects were selected randomly from Guntur district of Andhra Pradesh (AP), South India. The demographic particulars viz., personal habits, duration of exposure to pesticides, types of pesticides used were collected from the study subjects using an interview schedule. Among them 76 subjects were farmers and the remaining individuals served as unexposed or controls. Blood samples from these subjects were collected for assessing the genetic damage by chromosomal aberrations (CAs) test and micronucleus test (MNT). RESULTS: The results of the study indicated that CA was significantly higher with 2.8% in farmers who were exposed to pesticides when compared to unexposed (0.72%). However, there was a minor difference in MN with 0.13% and 0.12% between exposed and unexposed which was not statistically significant (p < 0.05). CONCLUSION: A correlation between CA frequency and exposure to benzene hexachloride (BHC) pesticide residue was observed.