Pesticide Use, Poisoning, and Knowledge and Unsafe Occupational Practices in Thailand

Comparison of microbial diversity and metabolic activities in organic and conventional rice farms in Thailand

Studies of the soil microbial community have revealed that several factors, both biotic and abiotic, can influence the community structure, diversity, and function. Human agricultural practice has been one of the key factors that affect microbial structure in soil. In this study, we examined the effect of two rice farming practices (i.e., conventional and organic) on soil microbial diversity and their metabolic activities. We proposed that the use of herbicides and chemical fertilizers in the conventional rice farming may decrease the soil microbial diversity and that it may lead to a decline in soil quality. However, our results show that there is no significant difference in the soil chemical properties, microbial diversity, and microbial metabolic activities between the two agricultural management systems. The wetland water cycling regime of rice agriculture in Thailand perhaps prevents the accumulation of chemicals in the soil, thus subdue the effect of these chemicals on soil microbes. Furthermore, our results showed that the key determinant of soil chemical properties as well as microbial community structure and diversity is the soil physical property, while the farming activity influences the microbial metabolic functions. These findings indicate the complex nature of the soil, microbes, and human farming interactions.IMPORTANCERice is a major export commodity in Thailand. As such, an understanding of the effect of conventional or organic farming approaches on soil microbial community could enable a suitable farming management. In this study, microbial communities were surveyed and compared between the two rice farming practices for their diversity and metabolic activities. Results showed no significant differences in microbial community structure and diversity between the two rice farming practices, but significant differences were observed due to the soil type, namely, clay, silty clay, silty clay loam, loam, and silty loam. Interestingly, significant differences in metabolic functions were also observed in different soil farming activities, such as land rest, period of growth, and post-burning, but not due to conventional or organic practices. These findings showed that the soil physical type and the farming activity impact the microbial community more than whether it is conventional or organically farmed.

Insecticide exposure and associated acute health effects in farmers in a rice growing district of India

This study investigated insecticide usage and associated acute health hazards in rice farming in Odisha, India. A retrospective cross-sectional study design was used to collect data from 139 participants, in the post-monsoon period, 2023. The participants were overwhelmingly male, mostly aged 30 and over, with basic literacy and a range of educational attainment, three-quarters ceasing education by 10th grade and a significant number never attending school. Most farmers/farmworkers used low or moderately toxic insecticides in low doses, typically 3 times/year. However, uptake of appropriate PPE was poor when mixing and applying insecticides. Almost two-thirds (63.4%) of participants reported discomfort/illness after insecticide exposure. Over 90% reported up to 3 symptoms, most experiencing skin irritation. The reported health symptoms were significantly higher among those who ate and drank during insecticide application, compared to those who did not. The number of symptoms reported was also significantly higher in participants who had seen or heard of community insecticide poisoning cases in the previous 12 months, compared with those who had not. Further research is needed on barriers to using effective PPE and on information and training on risks and controls of insecticide exposure that are appropriate for rice farmers in Odisha, India.

Biological Monitoring of Glyphosate Exposure among Knapsack Sprayers in Khon Kaen, Thailand

Sprayers' exposure to glyphosate was analyzed through detection of its biomarker in spot urine biological monitoring, and the health risk was assessed using the biomatrix model. Urine samples were collected from 15 sprayers after spraying, and the glyphosate concentration was determined by using the DLLME-HPLC method with a UV detector. The calibration curve for glyphosate was linear in the range of 0.4-100 µg/L, while the limits of detection and quantification were 0.1 µg/L and 0.4 µg/L, respectively. The human health risk was estimated using the hazard quotient (HQ) and the biomatrix of risk assessment. The internal dose ranged from 0.0001 to 0.0021 mg/kg b.w./day. The non-cancer HQ showed no potential health risk concerns (HQ < 1). The biomatrix of health risk assessment, based on urinary glyphosate concentration, exhibited a strong correlation with the health risk matrix model. This correlation was determined by considering the likelihood of exposure, calculated from the quantity of glyphosate used and the usage of personal protective equipment (r = 0.854, p < 0.001). Although low risk was observed in sprayers, proper PPE use and the application of more knowledge are required. The simplified health risk assessment can be used for easy self-assessment of risk in preventive action regarding health risk awareness among sprayers.

Occupational Exposure to Pesticides as a Risk Factor for Sleep Disorders

Inadequate sleep has been linked to a variety of impairments in bodily functions, including endocrine, metabolic, higher cortical function, and neurological disorders. For this reason, the aim of this study was to analyze the link between occupational pesticide exposure and sleep health among farmers in Almeria. A cross-sectional study was conducted among a population living on the coast of Almeria (southeastern Spain), where about 33,321 hectares of land are used for intensive agriculture in plastic greenhouses. A total of 380 individuals participated in the study: 189 greenhouse workers and 191 control subjects. The participants were contacted during their annual scheduled occupational health survey. Data on sleep disturbances were collected using the Spanish version of the Oviedo Sleep Questionnaire. Agricultural workers were found to be at a significantly higher risk of insomnia, especially among those who did not wear protective gloves (OR = 3.12; 95% C.I. = 1.93-3.85; p = 0.04) or masks (OR = 2.43; 95% C.I. = 1.19-4.96; p = 0.01). The highest risk of insomnia related to pesticide applicators was observed in those who did not wear a mask (OR = 4.19; 95% C.I. = 1.30-13.50; p = 0.01) or goggles (OR = 4.61; 95% C.I. = 1.38-10.40; p = 0.01). This study supports previous findings indicating an increased risk of sleep disorder in agricultural workers exposed to pesticides at work.

Important role of the government in reducing pesticide use and risk sustainably in Thailand: Current situation and recommendations

Agriculture is an important aspect of Thailand's GDP and development. It ranks as the 8th largest exporter in the world, however, pesticide use associated with the agriculture is ranked 18th in the world and 5th in Asia. Previous studies have clearly stated that pesticides are a threat to human health and the environment. The government is now making efforts to address pesticide use and the health impacts of pesticide use, however, these efforts are still in need of completion. This paper aims to summarize: (1) the current situation with regard to pesticide use in Thailand; (2) the current situation with regard to pesticide poisoning in Thailand; and (3) important role of government in reducing pesticide use and risk sustainably in Thailand: current situation and recommendations. This article suggests that government is a significant driver for reducing pesticide use and risk sustainably and the establishment of push and pull policies, legislation, and strategies. The government needs to strictly adhere to international conventions. Introducing a pesticide tax is essential to reduce redundant pesticide use. Updating of the current act, specific regulations with regard to pesticides and strict enforcement are urgently required. Licensing pesticide applicators should be implemented continuously. Promotion of alternative pest management is needed by supportive production inputs, technology, and markets as well as the development of a monitoring and certification system. Educating consumers on how to choose safe agricultural products and reduce risk from pesticide residues in the products is also necessary. All approaches should be implemented simultaneously and instantly. Importantly, the government needs to cooperate with agricultural sectors, health and environmental sectors, private sectors, as well as food industries to tackle complicate issues in a sustainable manner and lower pesticide use and risk sustainably in Thailand.

Exposure to organophosphate insecticides, inappropriate personal protective equipment use, and cognitive performance among pesticide applicators

Inappropriate use of personal protective equipment (PPE) among pesticide applicators may increase urinary organophosphate (OP) metabolite levels and subsequently increase risks of cognitive performance. Therefore, this study aims to (1) compare urinary OP metabolite levels and cognitive performance between pre-and post-pesticide application seasons; (2) PPE use and factors associated with PPE use linked to increased urinary OP metabolite levels during pesticide application; and (3) the association between urinary OP metabolite levels and cognitive performance. This longitudinal follow-up study on 79 pesticide applicators was carried out between October 2021 and January 2022. The applicators were interviewed, collected urine samples, and tested for cognitive performance in pre-and post-pesticide application seasons. The results found that the levels of urinary OP metabolites in post-application season were significantly higher than those in pre-application season (p < 0.001). Multiple linear regression analysis found that increased total diethylphosphate (DEP) and total dialkylphosphate (DAP) levels were associated with not wearing gloves while mixing pesticides [beta (β) ± standard error (SE) = -43.74 ± 18.52, 95% confidence interval (95% CI) = -80.84, -6.64 for total DEP and -50.84 ± 19.26, 95% CI = -89.41, -12.26 for total DAP] and also with not wearing a mask while spraying pesticides (β ± SE = -31.76 ± 12.24, 95% CI = -56.28, -7.24 for total DEP and -33.20 ± 12.63, 95% CI = -58.49, -7.92 for total DAP) after adjusting for covariates. The scores of Montreal Cognitive Assessment-Thai, Thai Mental State Examination, and Mini-Cognitive test in post-pesticide application were significantly lower than those in pre-pesticide application (p < 0.001). However, no association was found between urinary OP metabolite levels and cognitive decline. Our findings indicate that inappropriate PPE use during pesticide application was the major factor affecting urinary OP metabolite levels among pesticide applicators. Wearing gloves when mixing pesticides and a mask when spraying pesticides were key factors in reducing occupational exposure to OP. Exposure to OP at low levels and for short periods of exposure may not affect cognitive performance significantly. Therefore, long-term exposure and exposure to high levels of OP should be investigated further.

Mitochondrial dysfunction from malathion and chlorpyrifos exposure is associated with degeneration of GABAergic neurons in Caenorhabditis elegans

Toxicity resulting from off-target effects, beyond acetylcholine esterase inhibition, for the commonly used organophosphate (OP) insecticides chlorpyrifos (CPS) and malathion (MA) was investigated using Saccharomyces cerevisiae and Caenorhabditis elegans model systems. Mitochondrial damage and dysfunction were observed in yeast following exposure to CPS and MA, suggesting this organelle is a major target. In the C. elegans model, the mitochondrial unfolded protein response pathway showed the most robust induction from CPS and MA treatment among stress responses examined. GABAergic neurodegeneration was observed with CPS and MA exposure. Impaired movement observed in C. elegans exposed to CPS and MA may be the result of motor neuron damage. Our analysis suggests that stress from CPS and MA results in mitochondrial dysfunction, with GABAergic neurons sensitized to these effects. These findings may aid in the understanding of toxicity from CPS and MA from high concentration exposure leading to insecticide poisoning.

External Supervision, Face Consciousness, and Pesticide Safety Use: Evidence from Sichuan Province, China

Clarifying the factors influencing the safe use of pesticide is essential for scientific decision making to effectively manage pesticide use and promote sustainable agroecological development. The study aims to explore the factors influencing farmers' safe use of pesticides from the perspectives of external supervision and face consciousness. Using survey data covering 534 farm households in Sichuan province, this study empirically analyzes the influence mechanisms of external supervision, face consciousness, and their interaction terms on farmers' safe use of pesticides by employing the binary logit and IV-2SLS model, and further reveals their intergenerational differences on this basis. The results show that external supervision and positive face consciousness have significantly positive effects on pesticide safety use by farmers; market supervision and ability-type face, respectively, play the biggest role among them. Furthermore, there is an interaction effect between external supervision and face consciousness with respect to pesticide safety use. Farmers with different generation farms are influenced differently by external supervision and face consciousness. The behaviors of the new generation farmers to safely use pesticide are principally influenced by government supervision, market supervision, and ability-type face; in contrast, the ones of the older generation farmers are mainly influenced by market supervision, organization supervision, and relationship-type face.

Differences in Knowledge, Awareness, Practice, and Health Symptoms in Farmers Who Applied Organophosphates and Pyrethroids on Farms

OBJECTIVE

This cross-sectional study aimed to examine farmers' knowledge, awareness, practices regarding pesticide use, and prevalence of health symptoms related to pesticides exposure among farmers who applied organophosphates (OP) and pyrethroids (PY).

METHODS

Data regarding demographic variables and health symptoms pertinent to pesticide use was collected from 67 farmers who applied OP and 50 farmers who applied PY using interviews from January to March 2021.

RESULTS

The farmers who applied OP had lower knowledge, awareness, and prevention practices regarding pesticide use than those who applied PY. After adjustment of covariate variables, the farmers who applied OP had a significantly higher prevalence of respiratory conditions (OR = 8.29 for chest pain, OR = 6.98 for chest tightness, OR = 27.54 for dry throat, and OR = 5.91 for cough), neurological symptoms (OR = 10.62 for fatigue and OR = 6.76 for paresthesia), and neurobehavioral symptoms (OR = 13.84 for poor concentration, OR = 3.75 for short term memory, and OR = 8.99 for insomnia) related to pesticide exposure than those who applied PY.

CONCLUSION

Our findings suggest that OP had a more adverse effect on human health than PY, resulting in a higher prevalence of pesticide-related symptoms. The outcomes of this study have the benefit of providing vital information for all stakeholders with regard to the implementation of safe practices in the utilization of personal protective equipment (PPE) and pesticide use in a health intervention and health promotion program.

Efficiency of Gum Rosin-Coated Personal Protective Clothing to Protect against Chlorpyrifos Exposure in Applicators

An ideal theoretical model for personal protective clothing (PPC) is to protect wearers from external workplace hazards while meeting certain ergonomic requirements. This study aims to compare the efficiency of different personal protective clothing in its protection against chlorpyrifos, including gum rosin-coated PPC, commercial PPC (Tychem^® coverall), and everyday clothing, during application under field conditions. Perception of discomfort and physiological effects after wearing PPC were also investigated. Thirty-one applicators were invited and consented to participate in the study. The study established that the median percentage of chlorpyrifos protection efficiency was 90.7% for commercial PPC, 89.2% for gum rosin-coated PPC, and 76.5% for everyday PPC. When the protection efficiency was compared among the different types of PPC, the percentage protection efficiency of gum rosin-coated PPC was not significantly different from that of commercial PPC. The percentage protection efficiencies of commercial PPC and gum rosin-coated PPC were significantly higher than that of everyday PPC. The major characteristics of gum rosin-coated PPC were water-repellency, breathability, low cost, and ease of manufacture. Therefore, this study suggests that gum rosin-coated PPC is a reasonable alternative PPC for farmers, particularly in low and middle-low-income countries and tropical climates, to protect against pesticides while providing acceptable comfort.

Investigation of Prenatal Pesticide Exposure and Neurodevelopmental Deficits in Northern Thailand: Protocol for a Longitudinal Birth Cohort Study

BACKGROUND

Prenatal exposure to pesticides has been linked to adverse neurodevelopmental outcomes. Gaps exist in the current literature about the timing and magnitude of exposures that result in these adverse outcomes.

OBJECTIVE

The Study of Asian Women and their Offspring's Development and Environmental Exposures (SAWASDEE) cohort was established to investigate the impact of prenatal exposure to pesticides on early indicators of cognitive and motor skills, inhibitory control, emotion regulation, and memory that have been found to be important in the development of subsequent neurobehavioral and neurodevelopmental diseases. The overarching goal is to find earlier predictors of potential adverse neurologic outcomes in order to enable earlier interventions that could result in better outcome prognoses.

METHODS

Recruitment of this prospective, longitudinal birth cohort began in July 2017 and was completed in June 2019 in Chom Thong and Fang, 2 farming districts in Chiang Mai Province in northern Thailand. Follow-up of the study participants is ongoing. During pregnancy, 7 questionnaires were administered. Time-resolved biospecimen samples were collected monthly (for urine) and during each trimester (for blood) during antenatal care visits. Medical records were abstracted. Infants were administered the NICU Network Neurobehavioral Scale (NNNS) test at 1 month of age. A total of 322 mother-child pairs completed the NNNS test. All children will be followed until 3 years of age and undergo a series of neurodevelopmental tests. We will complete several additional exposure related analyses.

RESULTS

A total of 1298 women were screened, and of those, 394 (30.35%) women were enrolled. The mean gestational age at enrollment was 9.9 weeks (SD 2.6). Differences in literacy were observed between Chom Thong and Fang participants. In Fang, about 54 of 105 (51.4%) participants reported being able to read in Thai compared to about 206 of 217 (94.9%) participants in Chom Thong. The percentages were comparable for reporting to be able to write in Thai.

CONCLUSIONS

This longitudinal birth cohort study will inform risk assessment standards for pregnant women in Thailand and other countries. Building awareness of how insecticide exposure during specific windows of pregnancy affects the neurodevelopmental trajectories of children in developing countries is a specific need recognized by the World Health Organization.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/31696.

Impact of COVID-19 Pandemic on Daily Lives, Agricultural Working Lives, and Mental Health of Farmers in Northern Thailand

This study aims to determine the impact of COVID-19 on the daily lives, agricultural working lives, and mental health of farmers in northern Thailand. This cross-sectional study was carried out in September and October 2021 by interviews. From the stratified random sampling, 2046 farmers responded. There were five sections on the interview form, including demographics, daily life, agricultural working life, stress, and depression experienced during the COVID-19 pandemic. The results show that COVID-19 negatively affected the daily lives of the farmers, making it worse by 61.2%. COVID-19 increased the cost of planting (57.4%) and the cost of agrochemicals and fertilizers (69.9%). It also decreased the prices of agricultural products (73.5%) as well as agricultural extensions (66.5%). The markets and logistics of agricultural products during the pandemic were more difficult than before it (72.8% and 65.1%, respectively). Half of the farmers (50.3%) had moderate stress, and the highest scores were for the loss of household income (mean ± SD = 3.92 ± 0.94) and increased household expenses (mean ± SD = 3.92 ± 0.98). With regard to depression, 19.6% of farmers had depressive symptoms, and the multivariate analysis shows that the mental health of farmers was associated with the changes in their daily and agricultural working lives, as well as with financial problems. The remarkable findings indicate that the farmers who had high and extremely high stress levels had a higher prevalence of depression than the farmers who had no stress (adj.OR = 10.10 and 22.45, respectively). Our results lead to the conclusion that the COVID-19 crisis had an impact on the daily lives, agricultural working lives, and mental health of farmers. The results of this study can be used to provide pertinent guidance, and they have implications for government and other relevant organizations in their COVID-19 efforts to improve agricultural systems and sustain the mental health of farmers.

Urinary Concentrations of Dialkylphosphate Metabolites of Organophosphate pesticides in the Study of Asian Women and their Offspring's Development and Environmental Exposures (SAWASDEE)

BACKGROUND

Measurements of urinary dialkyl phosphate (DAP) metabolites are often used to characterize exposures to organophosphate (OP) insecticides; however, some challenges to using urinary DAP metabolites as an exposure measure exist. OP insecticides have short biological half-lives with measurement in a single urine sample typically only reflecting recent exposure within the last few days. Because of the field staff and participant burden of longitudinal sample collection and the high cost of multiple measurements, typically only one or two urine samples have been used to evaluate OP insecticide exposure during pregnancy, which is unlikely to capture an accurate picture of prenatal exposure.

METHODS

We recruited pregnant farmworker women in Chom Thong and Fang, two districts of Chiang Mai province in northern Thailand (N = 330) into the Study of Asian Women and their Offspring's Development and Environmental Exposures (SAWASDEE) from 2017 to 2019. We collected up to 6 serial urine samples per participant during gestation and composited the samples to represent early, mid, and late pregnancy. We measured concentrations of urinary DAP metabolites in the composited urine samples and evaluated the within- and between-participant variability of these levels. We also investigated predictors of OP insecticide exposure.

RESULTS

DAP metabolite concentrations in serial composite samples were weakly to moderately correlated. Spearman correlations indicated that composite urine samples were more highly correlated in Fang participants than in Chom Thong participants. The within-person variances (0.064-0.65) exceeded the between-person variances for DETP, DEP, ∑DEAP, DMP, DMTP, ∑DMAP, ∑DAP. The intraclass correlations (ICCs) for the volume-based individual metabolite levels (ng/mL) ranged from 0.10 to 0.66. For ∑DEAP, ∑DMAP, and ∑DAP the ICCs were, 0.47, 0.17, 0.45 respectively. We observed significant differences between participants from Fang compared to those from Chom Thong both in demographic and exposure characteristics. Spearman correlations of composite samples from Fang participants ranged from 0.55 to 0.66 for the ∑DEAP metabolite concentrations in Fang indicating moderate correlation between pregnancy periods. The ICCs were higher for samples from Fang participants, which drove the overall ICCs.

CONCLUSIONS

Collecting multiple (∼6) urine samples during pregnancy rather than just 1 or 2 improved our ability to accurately assess exposure during the prenatal period. By compositing the samples, we were able to still obtain trimester-specific information on exposure while keeping the analytic costs and laboratory burden low. This analysis also helped to inform how to best conduct future analyses within the SAWASDEE study. We observed two different exposure profiles in participants in which the concentrations and variability in data were highly linked to the residential location of the participants.

Association between Haematological Parameters and Exposure to a Mixture of Organophosphate and Neonicotinoid Insecticides among Male Farmworkers in Northern Thailand

Exposure to insecticides may result in various health problems. This study investigated the association between haematological parameters and exposure to a mixture of organophosphate (OP) and neonicotinoid (NEO) insecticides among male farmworkers in Fang district, Chiang Mai province, northern Thailand. Concentrations of urinary dialkylphosphates, non-specific metabolites of OPs, and NEOs and their metabolites and haematological parameters were measured in 143 male farmworkers. The Bayesian kernel machine regression model was employed to evaluate the associations. Exposure to a mixture of insecticides was significantly associated with the mean corpuscular haemoglobin concentration (MCHC) when the concentrations of all the compounds and their metabolites were at the 60th percentile or higher compared with the 50th percentile. Furthermore, exposure to clothianidin (CLO) showed a decreasing association with MCHC when all the other insecticides were at their mean concentrations. CLO was the most likely compound to reduce MCHC, and this was confirmed by sensitivity analysis. These findings suggest that exposure to NEO insecticides, especially CLO, affects the haematological status relating to haemoglobin parameters.

Insecticide Filtration Efficiency of Respiratory Protective Equipment Commonly Worn by Farmers in Thailand

Farmers are at a high risk of inhalation exposure when handling pesticides. Thai farmers usually protect themselves against pesticide exposure by wearing commercial respiratory protective equipment (RPE) available from rural community markets. However, scientific data regarding the pesticide filtration efficiency of RPE commonly worn by farmers is limited. Thus, this study aimed to investigate the efficiency of insecticide filtration of various RPE commonly worn by farmers in Thailand. The half facepiece respirator was used as a control to compare the results with other RPE. Ten types of RPE were selected for testing. The filtration efficiency of each RPE against insecticides was tested in a laboratory. The remarkable findings were that a surgical mask demonstrated the least filtration efficiency of all tested insecticides, with a range of 25.7-61.5%. The RPE available in rural markets of Thailand had a filtration efficiency within a range of 64.9-95.4%, whereas a half facepiece respirator was the most efficient in filtering insecticides, with a range of 96.5-98.9%. Therefore, our results suggest that the RPE most frequently worn by farmers may not provide adequate protection when compared with the respirator. However, considerations around RPE use in low-and middle-income countries and tropical climate conditions should be based on pesticide toxicity and practical use, ensuring balance between the risks from pesticide exposure and acceptance of PPE use.

Factors associated with respiratory symptoms among herbicide applicators and assistant applicators in maize field

A cross-sectional study was conducted with 3,291 maize farmers enrolled whose main roles were herbicide applicators and assistant applicators. This study aimed to compare the prevalence of respiratory symptoms and the use of personal protective equipment (PPE) between herbicide applicators and assistant applicators, and determine factors associated with respiratory symptoms. Our results suggest that wheeze and dyspnea were associated with the task on the farm (adj. OR = 10.33 for wheeze and 24.13 for dyspnea), amount of herbicide use (adj. OR = 1.95 for wheeze and 1.41 for dyspnea), frequency of herbicide use (adj. OR = 2.87 for wheeze and 4.08 for dyspnea), not always wearing a mask (adj. OR = 1.49 for wheeze and 3.17 for dyspnea), not always wearing gloves (adj. OR = 2.63 for wheeze and 2.44 for dyspnea), and not always wearing goggles (adj.OR = 2.01 for dyspnea) after adjusting for confounding factors.

Carbofuran cytotoxicity, DNA damage, oxidative stress, and cell death in human umbilical vein endothelial cells: Evidence of vascular toxicity

Carbofuran is a broad-spectrum carbamate insecticide, which principally inhibits the acetylcholinesterase (AChE) enzyme in the nervous system. Nonetheless, their selective action is not restricted to a single species and expanded to humans. No studies are available on the toxicological effects of carbofuran in the endothelial cells (ECs), which first confronts the toxicants in blood vessels. Hence, we have exposed the human umbilical vein ECs (HUVECs) with carbofuran for 24 h, which significantly reduced the cell survival to 25.16% and 33.48% at 500 and 1,000 μM analyzed by MTT assay. In the neutral red uptake (NRU) assay, 16.68%, 30.99%, and 58.11% survival decline was found at 250, 500, and 1,000 μM of carbofuran. HUVECs exposed to carbofuran showed significant increase in the intracellular reactive oxygen species (ROS), indicating oxidative stress at low concentrations. In parallel, HUVECs showed hyperpolarization effects in the mitochondrial membrane potential (ΔΨm) upon carbofuran exposure. Carbofuran induced DNA damage in HUVECs measured as 8.80, 11.82, 35.56, and 79.69 Olive tail moment (OTM) in 100-, 250-, 500-, and 1,000-μM exposure groups. Flow cytometric analysis showed apoptotic peak (SubG1) and G2M arrest in the HUVECs exposed to carbofuran. Overall, our novel data confirm that carbofuran is toxic for the EC cells, especially at the higher concentrations, which may affect the vascular functions and possibly angiogenesis. Hence, carbofuran should be applied judiciously, and detailed vascular studies are warranted to gain an in-depth information focusing the transcriptomic and translation changes employing suitable in vivo and in vitro test models.

Urinary organophosphate metabolites and oxidative stress in children living in agricultural and urban communities

Exposure to organophosphate (OP) pesticides in children may increase oxidative stress, resulting in the development of chronic diseases. This study aims to compare urinary OP metabolites and oxidative stress between children in agricultural and urban communities. The study also investigated the factors associated with urinary OP metabolites among children. Urine samples were collected from children for measuring levels of OP metabolites, glutathione (GSH), and malondialdehyde (MDA). The remarkable findings were that total dialkylphosphate (DAP) levels detected among children in this agricultural community were significantly higher than those from the urban community (P = 0.001). Multiple linear regression showed that total diethylphosphate (DEP) levels among children in the agricultural community were negatively associated with distances from children's residence to the agricultural fields (β ± SE. = - 1.535 ± 0.334, 95%CI = - 2.202, - 0.863) and positively associated with playing on farms (β ± SE. = 0.720 ± 0.342, 95%CI = 0.036, 1.405). In addition, total dimethylphosphate (DMP) levels were positively associated with children working on farms (β ± SE. = 0.619 ± 0.264, 95%CI = 0.091, 1.147). Importantly, GSH levels among children in the agricultural community were significantly lower than those in the urban community (P < 0.001), but MDA levels did not differ. These results therefore suggest that children can be exposed to OPs both outdoors and indoors. Our results also provide supporting evidence that OP exposure can cause oxidative stress in children. As oxidative stress contributes to several chronic diseases, a good proposed strategy for the future would include measurement of oxidative stress biomarkers among children exposed to OPs as an early warning of chronic diseases.

Factors affecting use of personal protective equipment and pesticide safety practices: A systematic review

An evidence-based understanding of factors influencing PPE use and pesticide safety practices has the benefit of facilitating the design of interventions to minimize exposure to pesticides and the promotion of the utilization of PPE and safety practices among agricultural pesticide handlers. The aim of this study, therefore, is to review the available literature on the use of PPE in agricultural pesticide handlers in world regions, and also the factors associated with the use of PPE and pesticide safety practices in farmers and farm workers. Full-text articles published on PubMed, Scopus, and ISI databases between 1999 and 2019 were reviewed and the scientific evidence was evaluated. One hundred and twenty-one articles were eligible for inclusion in this quantitative synthesis: 110 evaluated PPE use in agricultural pesticide handlers, and 23 focused on factors affecting PPE use and pesticide safety practices. Considerable evidence was found to show that the most basic PPE worn among pesticide handlers in all world regions was a long sleeve shirt (66.1%), long sleeve trousers (71.1%), and a hat (47.3%). The lowest basic PPE worn was an apron (8.6%), goggles (24.3%), gloves (40.5%), boots (42.3%), and mask (43.2%). The PPE worn (except for an apron) was proportionally higher in farmers than in farm workers. There is considerable evidence to suggest that the significant determinants associated with PPE use and pesticide safety practices are as follows: (1) demographic factors (i.e. education/literacy level, experience of illness, income); (2) farm structure factors (i.e. farm size); (3) behavioral and psychosocial factors (i.e. contact with pesticides, perceptions, attitudes, awareness, norms and beliefs); and (4) environmental factors (i.e. information about pesticides, access to extension services, training program, and farm organization). Therefore, there is a recognizable need for a life-long education program with training to change the perception and behavior of pesticide handlers sustainably.

Development of Personal Protective Clothing for Reducing Exposure to Insecticides in Pesticide Applicators

Wearing appropriate personal protective equipment during the application of pesticides is one method of reducing dermal exposure to pesticides. Thus, the aim of this research is to develop personal protective clothing (PPC) coated with gum rosin and investigate the efficiency of its level of protection against chlorpyrifos and cypermethrin. Comparison of the protection efficiency of each PPC with Tychem^® C coveralls was also investigated. Five commercially available cotton fabrics were chosen for tailoring the PPC, and then, the PPC was coated with a gum rosin finish to provide water repellence. The efficiency of the level of protection of the gum rosin-coated PPC against insecticides was tested in a laboratory (closed chamber). The remarkable findings were that the % protection efficiencies for all the PPC, with the exception of one, were not significantly different to those for Tychem^® C coveralls. The protection efficiencies ranged from 99.85% to 99.97% against chlorpyrifos and 99.11% to 99.89% against cypermethrin. Therefore, our results suggest that gum rosin-coated clothing provided satisfactory levels of protection against insecticides and could be considered as suitable protective clothing for pesticide applicators. Choice of an appropriate fabric for coating with gum rosin also needs to be considered. A further study in field conditions is warranted to confirm the protection efficiency in a working environment.

Bioaccumulation and Distribution Behavior of Endosulfan on a Cichlid Fish: Differences Between Exposure to the Active Ingredient and a Commercial Formulation

Persistent organic pollutants reach aquatic ecosystems during application and can bioconcentrate/biomagnify because of their lipophilic nature. Toxicological studies focus almost exclusively on the active ingredients of pesticides, instead of commercial formulations, whose toxicity can differ as a result of nonspecified ingredients. The intensive use of endosulfan as a wide-ranging insecticide over the last few decades makes it one of the most frequently detected contaminants in the aquatic environment, even after it has been restricted worldwide. The aim of the present study was to evaluate the bioaccumulation and organ distribution of waterborne endosulfan in the freshwater fish Cichlasoma dimerus, comparing the active ingredient and a commercial formulation. Males were exposed to 0.7 μg/L endosulfan for 2 wk, which was quantified (gas chromatography with an electron capture detector) in the liver, testes, gills, brain, and muscle. The results suggest rapid metabolism of α-endosulfan and β-endosulfan isomers to endosulfan sulfate (endosulfan-S) in tissues. Isomer levels were highest in gills, indicative of recent uptake. Levels of endosulfan-S were highest in liver and testes for the active ingredient and testes and brain for the commercial formulation. For the active ingredient, endosulfan-S levels showed a positive correlation with organ-lipid percentage. No correlation was evident for the commercial formulation, indicating that the presence of adjuvants alters endosulfan distribution because gills and liver showed a higher uptake and mobilization of β-endosulfan. These differences in organ distribution may alter tissue-specific toxicity; therefore, additives cannot be considered inactive even if nontoxic. Environ Toxicol Chem 2020;39:604-611. © 2019 SETAC.

Types of Exposure Pesticide Poisoning in Jiangsu Province, China; The Epidemiologic Trend between 2006 and 2018

BACKGROUND

Pesticide poisoning is an important issue in rural China, and is also a major public health problem that affects the health of farmers. The purpose of this paper is to explore the epidemiology of pesticide poisoning in Jiangsu Province, and to put forward the relevant suggestions on the logical and discerning utilization of the pesticides.

METHODS

According to the data of the pesticide poisoning report card established by the health hazard detection information system, the cases of pesticide poisoning in Jiangsu Province from 2006 to 2018 were exported to Excel, and the database of pesticide poisoning was established. Furthermore, the imported data was screened and collected. A descriptive statistical analysis had been employed on this data utilizing SPSS 20.0.

RESULTS

Between the years 2006 and 2018, 38,513 pesticide poisoning cases were registered in Jiangsu Province, with a downward trend. Meanwhile, 77.83% of poisoning cases involved insecticide poisoning, followed by herbicide and rodenticide. The greater part of the diverse sorts of studied insecticide poisoning cases involved people aged between 30 and 59 years (57.51%). Poisoning cases caused by rodenticide accounted for a large proportion of people aged between 0 and 14 years (23.72%) in non-occupational pesticide poisoning. Regarding seasons, it was distinguished that more insecticide cases were reported in autumn (46.95% of the total number of cases). Pesticide poisoning was reported in 13 cities of Jiangsu Province, and among these, insecticide poisoning was reported mainly from the northern Jiangsu area, which was the same as rodenticide and herbicide.

CONCLUSIONS

Although there is a decreased risk for pesticide poisoning among farmworkers in Jiangsu Province, the number of farmworkers with pesticide poisoning is still high. Further management of the pesticide utilization is necessary, especially insecticide. More attention ought to be paid to the protection of vulnerable groups, including children and the elderly.

Effects of prenatal and postnatal exposure to organophosphate pesticides on child neurodevelopment in different age groups: a systematic review

Exposure to pesticides is a major factor in the cause of dysfunction in the nervous system and neurodevelopment disorders in children at critical periods of great vulnerability. The aim of this study was to review scientific evidence published on neurodevelopmental effects of prenatal and postnatal exposure to organophosphate pesticides (OPs) in different stages, including neonates, infants, toddlers, preschool children, and school-age children. Full-text articles published in PubMed, Scopus, and ISI databases between 1973 and 2019 were reviewed and the scientific evidence was evaluated. Results: Fifty studies were eligible for inclusion in this quantitative synthesis. Fifteen of these papers evaluated the effects on neonates and infants, 18 on the effects on toddlers and preschool children, and 24 the effects on school-age children. Considerable evidence suggests that prenatal exposure to OPs contributes to child neurodevelopment disorders in all stages, whereas data about the effects of postnatal exposure are limited. Therefore, the available evidence supports the theory that sensitive time-windows occur prenatally rather than postnatally. Although 45 out of the total 50 selected articles found an association between OP exposure and child neurodevelopment, some of the evidence is controversial. A standardized methodology is needed to enable the comparison of the results in several studies, and further research studies are needed to warrant firmer conclusions. A systematic review of this evidence should be performed continuously to update the state of knowledge regarding neurodevelopmental effects associated with OP exposure.

Changes in lung function and respiratory symptoms during pesticide spraying season among male sprayers

Exposure to pesticides via inhalation might impair lung function and develop further severe respiratory symptoms and diseases. Thus, the purpose of the study was to compare lung function between pre- and post-pesticide spraying seasons among male sprayers. The study also evaluated the association of lung function changes and other factors with respiratory symptoms. The follow-up study was conducted on 58 male sprayers. The subjects were interviewed and measured lung function before and after pesticide spraying season. The results found that forced vital capacity (FVC), forced expiratory volume in one second (FEV₁), and peak expiratory flow rate in the post-spraying season were significantly lower than in the pre-spraying season. With regard to respiratory symptoms, cough symptoms were associated with changes in FEV₁/FVC [odd ratio (OR) = 1.29, 95% confidence interval (CI) = 1.01-1.67)] and smoking status (OR = 12.95, 95%CI = 1.35-124.34). Phlegm symptoms were also associated with changes in FVC (OR = 2.07, 95%CI = 1.01-4.25) and FEV₁ (OR = 0.41, 95%CI = 0.18-0.91). The study provides evidence that pesticide spraying may increase risks for significant alteration of lung function and respiratory symptoms.