Exposure to pesticide as a risk factor for depression: A population-based longitudinal study in Korea

A prospective cohort study of persistent endocrine-disrupting chemicals and perceived stress

Persistent endocrine-disrupting chemicals (EDCs) can dysregulate the stress response. We evaluated associations between persistent EDCs and perceived stress among participants in the Study of Environment, Lifestyle, and Fibroids (n = 1394), a prospective cohort study of Black women. Participants completed the Perceived Stress Scale 4 (PSS-4) at baseline and every 20 months through 60 months (score range: 0-16); higher scores indicate higher stress. Endocrine-disrupting chemicals, including per- and polyfluoroalkyl substances, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides, were quantified in plasma samples at baseline. We fit bayesian kernel machine regression and linear mixed-effects models to estimate associations of EDCs (as a mixture and individually) with PSS-4 scores at baseline and at each follow-up visit, respectively. Increasing percentiles of the mixture were not strongly associated with PSS-4 scores at baseline, and no interactions were observed among EDCs. Several individual EDCs (eg, perfluorodecanoic acid, PCB 118, PBDE 99) were associated with higher PSS-4 scores at baseline or follow-up, and other EDCs (eg PCB 138/158) were associated with lower PSS-4 scores at baseline or follow-up. The directionality of associations for individual EDCs was inconsistent across follow-up visits. In conclusion, specific EDCs may be associated with perceived stress in Black women. This article is part of a Special Collection on Environmental Epidemiology.

Factors Associated with the Development of Depression and the Influence of Obesity on Depressive Disorders: A Narrative Review

Depression affects several aspects of life, including socioeconomic status, relationships, behavior, emotions, and overall health. The etiology of depression is complex and influenced by various factors, with obesity emerging as a significant contributor. This narrative review aims to investigate the factors associated with the development of depression, with a particular focus on the role of obesity. The literature search was conducted on PubMed, Embase, and PsycINFO from May to July 2024. The review highlights the impact of environmental and socioeconomic conditions; lifestyle choices, including physical activity and dietary habits; stress; traumatic experiences; neurotransmitter imbalances; medical and psychological conditions; hormone fluctuations; and epigenetic factors on depression. A key emphasis is placed on the inflammatory processes linked to obesity, which may drive the bidirectional relationship between obesity and depression. The findings suggest that obesity is associated with an increased risk of depression, potentially due to chronic inflammation, neurochemical dysregulation, and the emotional and social challenges related to weight stigma and obesity management. Understanding these interconnected factors is important for developing targeted interventions to address both obesity and depression, leading to improved quality of life for those affected.

Per- and polyfluoroalkyl substances (PFAS), perceived stress, and depressive symptoms in a prospective cohort study of black women

BACKGROUND

Per- and polyfluoroalkyl substances (PFAS) are endocrine-disrupting chemicals with neurotoxic properties. PFAS have been associated with depressive symptoms among women in some studies, but little research has evaluated the effects of PFAS mixtures. Further, no study has investigated interactions of PFAS-depression associations by perceived stress, which has been shown to modify the effects of PFAS on other health outcomes.

OBJECTIVE

In a prospective cohort study of reproductive-aged Black women, we investigated associations between PFAS and depressive symptoms and the extent to which perceived stress modified these associations.

METHODS

We analyzed data from 1499 participants (23-35 years) in the Study of Environment, Lifestyle, and Fibroids. We quantified concentrations of nine PFAS in baseline plasma samples using online solid-phase extraction-liquid chromatography-isotope dilution tandem mass spectrometry. Participants reported perceived stress via the Perceived Stress Scale (PSS-4; range = 0-16) at baseline and depressive symptoms via the Center for Epidemiologic Studies Depression Scale (CESD; range = 0-44) at the 20-month follow-up visit. We used Bayesian Kernel Machine Regression to estimate associations between PFAS concentrations, individually and as a mixture, and depressive symptoms, and to assess effect modification by PSS-4 scores, adjusting for confounders.

RESULTS

Baseline perfluorodecanoic acid concentrations were associated with greater depressive symptoms at the 20-month follow-up, but associations for other PFAS were null. The PFAS were not associated with depressive symptoms when evaluated as a mixture. The association between the 90th percentile (vs. 50th percentile) of the PFAS mixture with CES-D scores was null at the 10th (β = 0.03; 95 % CrI = 0.20, 0.25), 50th (β = 0.02; 95 % CrI = -0.16, 0.19), and 90th (β = 0.01; 95 % CrI = 0.18, 0.20) percentiles of PSS-4 scores, suggesting perceived stress did not modify the PFAS mixture.

CONCLUSION

In this prospective cohort study, PFAS concentrations-assessed individually or as a mixture-were not appreciably associated with depressive symptoms, and there was no evidence of effect modification by perceived stress.

Depressive symptoms and suicide attempts among farmers exposed to pesticides

Pesticides safeguard crop health but may diminish cholinesterase activity in farmers, potentially leading to psychiatric disorders like depression and suicide attempts. This study, with 453 participants (225 pesticide-exposed farmers, 228 non-farmers) in Almería, Spain, aimed to investigate the presence of depressive symptoms and suicide attempts, the decrease acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activity, and their relationship with pesticide exposure in farmers. Depressive symptoms were evaluated using the Spanish adaptation of the Beck Depression Inventory, and blood samples were analyzed for AChE and BChE activity. Farmers showed significantly increased risk of moderate/severe depression and suicide attempts compared to non-farmers (OR = 2.18; p = 0.001), with highest risks observed among mancozeb users (OR = 2.76; p = 0.001 for depression) and malathion users (OR = 3.50; p = 0.001 for suicide attempts). Findings emphasize elevated depression and suicide risks among pesticide-exposed farmers, particularly associated with chlorpyrifos, mancozeb, and malathion exposure.

Depression and Pesticide Exposure Among Male Farmers in Greece

OBJECTIVE

The objective of this study was to evaluate the relationship between pesticide exposure and depression.

METHODS

A cross-sectional study was performed in a study population of 252 Greek male farmers using the Center for Epidemiological Studies Depression scale. Cumulative pesticide exposure was categorized in three mutually exclusive groups related to lifetime pesticide use: low (<275 days, the reference group), intermediate (276 to 1200 days), and high (>1200 days). Acute pesticide exposure was categorized in pesticide poisoning events and high pesticide exposure events. Multivariable logistic regression analysis was performed, and odds ratios, 95% confidence intervals, and P values were presented.

FINDINGS

After adjusting for confounding factors, a positive significant association was found between both high-exposure group and high pesticide exposure events and depressive symptoms.

CONCLUSIONS

Apart from acute, high cumulative pesticide exposure may as well contribute to the development of depression.

Depression in Brazilian farmers: prevalence and associated factors

BACKGROUND

The unique characteristics of rural areas and agricultural work can contribute to the genesis of diseases, including mental disorders such as depression.

AIMS

To estimate the prevalence of and factors associated with depression symptoms in Brazilian farmers.

METHODS

A cross-sectional epidemiological study involving 784 farmers of the state of Espírito Santo/Brazil was carried out. Depression was identified using the Mini-International Neuropsychiatric Interview. Hierarchical logistic regression was used to assess the associated factors.

RESULTS

The prevalence of depression symptoms among farmers was 16.8% (n = 132). Of those experiencing symptoms, 6.1% (n = 48) we're currently experiencing a depressive episode, and 10.7% (n = 84) a recurrent depressive episodes. The associated factors were: female gender (OR 1.63; 95% CI 1.04-2.54), not owning the land (OR 1.79; 95% CI 1.11-2.89), professional dissatisfaction (OR 1.99; 95% CI 1.18-3.35), previous pesticide poisoning (OR 2.87; 95% CI 1.45-5.67), complex multimorbidity (OR 1.95; 95% CI 1.15-3.31) and occurrence of previous depressive episodes (OR 9.83; 95% CI 4.39-21.99).

CONCLUSIONS

A high prevalence of depression symptoms was identified among rural workers. Sociodemographic, occupational, clinical, and professional dissatisfaction factors were associated with a higher risk of depression symptoms in this population.

Pesticide Exposure or Pesticide Poisoning and the Risk of Depression in Agricultural Populations: A Systematic Review and Meta-Analysis

Evidence suggests that farm workers represent a high-risk population for the development of depression. The aim of the study was to clarify the association between pesticide exposure/poisoning and depression. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis were conducted in this systematic review and meta-analysis. Relevant studies were included through searching in PubMed, Scopus, Web of Science, ProQuest, CINAHL and pre-print services databases. A total of eight studies were included. A positive but non-significant association was observed between pesticide use and depression (OR = 1.123; 95% CI, 0.932-1.354, p-value = .221) while a significant positive association was observed between pesticide poisoning and depression (OR = 2.942; 95% CI, 1.791-4.831, p-value < .001). The present meta-analysis suggested clearly a significant positive association between pesticide poisoning and depression, confirming the hypothesis that pesticide poisoning is a risk factor of depression. It also revealed positive, yet non-significant association, between pesticide exposure and depression, a finding that enhances recent research but requires to be further supported by future cohort studies, including socioeconomic factors and biomarkers of depression.

Indicators of occupational pesticide exposure are associated with psychiatric symptoms

In southeastern Spain, intensive and highly productive agriculture under plastic also poses a risk to human health, as evidenced by reports on acute pesticide poisoning and its effects on mental health. However, knowledge of chronic exposures and their relationship to psychiatric disorders is still limited. This study analyzed the relationship between occupational exposure to pesticides and psychiatric disorders in farmers from Almería. A cross-sectional study was conducted amongst a coastal population in Almería, where over 32,800 ha of land are dedicated to intensive agriculture in plastic greenhouses. A total of 409 people participated in the study: 203 farmers and 206 control subjects. The highest risk of psychiatric disorders was observed in farmers living in areas of high exposure to pesticides, working in greenhouses (intensive agriculture), without protective goggles and without wearing masks. This study supports previous evidence of an elevated risk of psychiatric disorders among farm workers exposed to pesticides.

Occupational exposure to pesticides and symptoms of depression in agricultural workers. A systematic review

BACKGROUND

The use of pesticides can result in harm to both the environment and human health. There is a growing concern in the field of occupational health about the impact on the mental health of agricultural workers.

OBJECTIVES

The objective of this review was to systematize scientific evidence from the last ten years on the impact of occupational exposure to pesticides on the development of depression symptoms in agricultural workers.

METHODS

We conducted a comprehensive search in the PubMed and Scopus databases from 2011 to September 2022. Our search included studies in English, Spanish, and Portuguese that examined the association between occupational exposure to pesticides and symptoms of depression in agricultural workers, following the guidelines recommended by the PRISMA statement and the PECO strategy (Population, Exposure, Comparison, and Outcomes).

RESULTS

Among the 27 articles reviewed, 78% of them indicated a link between exposure to pesticides and the incidence of depression symptoms. The pesticides most frequently reported in the studies were organophosphates (17 studies), herbicides (12 studies), and pyrethroids (11 studies). The majority of the studies were rated as having intermediate to intermediate-high quality, with the use of standardized measures to assess both exposure and effect.

CONCLUSION

The updated evidence presented in our review indicates a clear association between pesticide exposure and the development of depressive symptoms. However, more high-quality longitudinal studies are necessary to control for sociocultural variables and utilize pesticide-specific biomarkers and biomarkers of depression. Given the increased use of these chemicals and the health risks associated with depression, it is crucial to implement more stringent measures to monitor the mental health of agricultural workers regularly exposed to pesticides and to enhance surveillance of companies that apply these chemicals.

Could pesticide exposure be implicated in the high incidence rates of depression, anxiety and suicide in farmers? A systematic review

Pesticide exposure and poisoning may rise the risk of mental health problems and suicidal tendencies. To explore the potential connection between chronic occupational exposure to pesticides and depression, anxiety, and suicide-related outcomes in farmers, a systematic review was performed. Systematic review protocol is available in PROSPERO registration number CRD42022316285. A total of fifty-seven studies met inclusion criteria: twenty-nine on depression or other mental disorders, twelve on suicide (two of them on both depression and suicide), and fourteen on pesticide poisoning or self-poisoning and death. Among the fifty-seven selected studies, eighteen were conducted in Asia, seventeen in North America, fourteen in South America, seven in European Union, one in Africa, and one in Australia/Oceania. Selected studies demonstrated an increased prevalence of depressive disorders in farmworkers exposed to pesticides as well as an increased self-reported prevalence of depression in this population. Moreover, previous pesticide poisoning increased the risk estimates for depression or other mental disorders as compared with chronic pesticide exposure. Severe pesticide poisoning and multiple poisoning showed increased risks of depressive symptoms compared with milder cases. In addition, financial difficulties and poor health were positively correlated with depression. Among studies on suicide, nine of them found that suicide rates increased in areas devoted to agriculture with intensive pesticide consumption. Moreover, studies demonstrate a higher suicide risk among farmers. The present review suggests more attention to the farmer's mental health and more detailed studies on occupational exposure to the mixture of these compounds.

Neurobehavioral Effects of Low-Dose Chronic Exposure to Insecticides: A Review

The modes of action of insecticides frequently involve a neurotoxic effect; therefore, the study of neurotoxic effects caused by long-term and low-dose insecticide exposure is of particular interest. This study looks at whether or not new studies conducted after 2009 and up to 2021 have provided new evidence for a better understanding of the actual neurobehavioral risk associated with long-term insecticide exposure. We selected and reviewed studies carried out on the neurobehavioral effects of neurotoxic insecticides (organophosphates and/or carbamates, pyrethroids, multiple or undefined insecticides, and organochlorines) considering occupational and non-occupational exposures. The articles were also scored and ranked based on seven parameters. Eighty-six studies were chosen for a final review process from among the 950 scientific papers identified. Twenty-six addressed occupational exposure and six environmental exposure. Among the latter group of studies, 17 focused on rural residents, to be assumed exposed because of living in rural areas, and 43 on the general population. Pending doubts have not been resolved in the last ten years due to the presence of contradictory and hardly comparable results and the fact that in most of the studies showing an evident neurobehavioral impairment the frequent presence of a previous episode of poisoning and hospitalization, with severe brain hypoxia, impaired the possibility of confirming the presence of a causal association with insecticide exposure. Interestingly, the most severely exposed groups, such as applicators who did not wear personal protective equipment, performed worse on neurobehavioral tests. As for residential exposure, there is sufficient evidence to suggest that prenatal OP exposure may increase the risk of ADHD in children.

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.

Acute Pesticide Poisoning in Tobacco Farming, According to Different Criteria

BACKGROUND

Brazil is one of the world's largest pesticide consumers, but information on pesticide poisoning among workers is scarce.

OBJECTIVE

To evaluate acute pesticide poisoning among tobacco growers, according to different criteria.

METHODS

This was a two-step cross-sectional study with 492 pesticide applicators. It used a 25 question pesticide-related symptoms (PRS) questionnaire and medical diagnosis for comparison with toxicological assessment. Associations were evaluated using Poisson regression.

RESULTS

10.6% reported two or more PRS, while 8.1% reported three or more. Furthermore, 12.2% received a medical diagnosis of poisoning. According to toxicologists, possible cases accounted for 14.2% and probable cases for 4.3%. PRS increased during the period of greater exposure. Those exposed to dithiocarbamates, sulfentrazone, pyrethroids, fipronil and iprodione exhibited more PRS. The number of exposure types, multi-chemical exposure, clothes wet with pesticides and spillage on the body/clothes were associated with acute poisonings. All criteria showed sensitivity greater than 79% for probable cases but only greater than 70% for medical diagnosis when compared to possible cases, presenting substantial Kappa agreement.

CONCLUSION

The prevalence of acute pesticide poisoning is much higher than officially recorded. Trained physicians can screen for pesticide poisoning. It is necessary to improve workers' education to reduce pesticide use and exposure to them.

Co-Benefits of Largescale Organic farming On huMan health (BLOOM): Protocol for a cluster-randomised controlled evaluation of the Andhra Pradesh Community-managed Natural Farming programme in India

The BLOOM study (co-Benefits of Largescale Organic farming On huMan health) aims to determine if a government-implemented agroecology programme reduces pesticide exposure and improves dietary diversity in agricultural households. To achieve this aim, a community-based, cluster-randomised controlled evaluation of the Andhra Pradesh Community-managed Natural Farming (APCNF) programme will be conducted in 80 clusters (40 intervention and 40 control) across four districts of Andhra Pradesh state in south India. Approximately 34 households per cluster will be randomly selected for screening and enrolment into the evaluation at baseline. The two primary outcomes, measured 12 months post-baseline assessment, are urinary pesticide metabolites in a 15% random subsample of participants and dietary diversity in all participants. Both primary outcomes will be measured in (1) adult men ≥18 years old, (2) adult women ≥18 years old, and (3) children <38 months old at enrolment. Secondary outcomes measured in the same households include crop yields, household income, adult anthropometry, anaemia, glycaemia, kidney function, musculoskeletal pain, clinical symptoms, depressive symptoms, women's empowerment, and child growth and development. Analysis will be on an intention-to-treat basis with an a priori secondary analysis to estimate the per-protocol effect of APCNF on the outcomes. The BLOOM study will provide robust evidence of the impact of a large-scale, transformational government-implemented agroecology programme on pesticide exposure and dietary diversity in agricultural households. It will also provide the first evidence of the nutritional, developmental, and health co-benefits of adopting agroecology, inclusive of malnourishment as well as common chronic diseases. Trial registration: Study registration: ISRCTN 11819073 (https://doi.org/10.1186/ISRCTN11819073). Clinical Trial Registry of India CTRI/2021/08/035434.

Neurotoxicity of pesticides in the context of CNS chronic diseases

Following the introduction and application of pesticides in human life, they have always been along with health concerns both in acute poisoning and chronic toxicities. Neurotoxicity of pesticides in chronic exposures has been known as one of the most important human health problems, as most of these chemicals act through interacting with some elements of nervous system. Pesticide-induced neurotoxicity can be defined in different categories of neurological disorders including neurodegenerative (Alzheimer, Parkinson, amyotrophic lateral sclerosis, multiple sclerosis), neurodevelopmental (attention deficit hyperactivity disorder, autism spectrum disorders, developmental delay, and intellectual disability), neurobehavioral and neuropsychiatric (depression/suicide attempt, anxiety/insomnia, and cognitive impairment) disorders some of which are among the most debilitating human health problems. In this review, neurotoxicity of pesticides in the mentioned categories and sub-categories of neurological diseases have been systematically presented in relation to different route of exposures including general, occupational, environmental, prenatal, postnatal, and paternal.

Potential Effects on Mental Health Status Associated with Occupational Exposure to Pesticides among Thai Farmers

Pesticide-related mental health issues in Thailand, an upper-middle-income country, are not well known. This study aimed to investigate the association between the history of occupational exposure to pesticides and the mental health of Thai farmers. A cross-sectional study was carried out in the areas around Chiang Mai, a large city in Northern Thailand, between June 2020 and January 2021. A total of 6974 farmers from six districts were interviewed to determine whether they regularly experienced symptoms related to mental health by the Self-Reporting Questionnaire (SRQ-20) as well as their lifetime history of agricultural pesticide exposure from 31 active ingredients and five functional categories: insecticides, herbicides, fungicides, rodenticides, and molluscicides. The cut-off of 6 was used to evaluate probable mental disorder. Most of the farmers under investigation were men (53.8%), with a mean age of 55.2 (11.7) years, and were involved mainly in the planting of rice, fruit, and vegetables. About 86.7% reported having used pesticides on their crops at some point in their lives-mostly glyphosate, paraquat, 2,4-D, methomyl, and carbofuran. All functional groups, as well as pesticide classes like organochlorines, organophosphates, and carbamates, were significantly associated with a higher risk of probable mental disorder based on exposure duration, frequency, personal protective equipment usage, and hygienic behavior. In a model with multiple pesticides, there was an association between mental disorder and exposure to endosulfan (AOR = 2.27, 95%CI = 1.26-4.08) and methyl parathion (AOR = 2.26, 95%CI = 1.26-4.06). Having previously reported pesticide poisoning symptoms was related to mental disorder (AOR = 7.97, 95%CI = 5.16-12.31), the findings provided evidence of pesticide exposure posing a risk to farmers' mental health, particularly long-term and high-intensity exposure.

Prevalence of Pesticide Use and Occupational Exposure Among Small-Scale Farmers in Western Ethiopia

OBJECTIVE

This study aims to assess the prevalence of pesticide use and its occupational exposure among small-scale farmers in the Kellem Wellega Zone of western Ethiopia.

METHODS

A cross-sectional study design using a structured questionnaire was used to collect data from 249 small-scale farmers' households through face-to-face interviews. Statistical analysis such as descriptive statistics, Chi-square test, and binary logistic regression analysis was applied, and a P-value <.05 at 95% CI was considered statistically significant.

RESULTS

The prevalence of pesticide use was 87.15%. About 44.2%, 40.2%, and 43.8% of the study participants were classified as having poor knowledge, poor practice, and negative attitude toward pesticide use, respectively. Thus, small-scale farmers whose age was greater than 40 years were 7.87 times more likely to be exposed to skin irritation than those whose age was less than 20 years (AOR = 7.87; 95% CI: 1.75-35.45) and skin contact (AOR = 0.37; 95% CI: 0.15-0.91). Most farmers who were directly involved in agriculture were 2.22 times more likely to be exposed to the inhalation of pesticide chemicals than those involved in another activity (AOR = 2.22; 95% CI: 1.14-4.33). Based on educational level, small-scale farmers who have a primary school and above were 81% less likely to inhale pesticide chemicals than those who did not have formal education (AOR = 0.19; 95% CI: 0.09-0.41). Furthermore, low-income small-scale farmers were 2.62 times more likely to be exposed to coughing (AOR = 2.62; 95% CI: 1.25-5.51) than high-income participants. Furthermore, farmers with good knowledge were 1.79 times more likely to be exposed to skin irritation than those with poor knowledge (AOR = 1.79; 95% CI: 1.0-3.17). Farmers with poor practice were 1.85 times more likely to show coughing symptoms than those with good practice (AOR = 1.85; 95% CI: 1.08-3.2), and farmers with good practice were 48% less likely to be exposed to headache than those with poor practice (AOR = 0.52; 95% CI: 0.31-0.88).

CONCLUSIONS

This study shows that small-scale farmers were exposed to pesticides through coughing, headache, skin irritation, inhalation, and skin contact. Low level of knowledge, poor practice, job, low income, older age, and educational level.

Analysis of serum levels of organochlorine pesticides and related factors in Parkinson's disease

BACKGROUND

There is evidence that environmental factors contribute to the onset and progression of Parkinson's disease (PD). Pesticides are a class of environmental toxins that are linked to increased risk of developing PD. However, few studies have investigated the association between specific pesticides and PD, especially in China, which was one of the first countries to adopt the use of pesticides.

METHODS

In this study, serum levels of 19 pesticides were measured in 90 patients with PD and 90 healthy spouse controls. We also analyzed the interaction between specific pesticides and PD. In addition, the association between pesticides and clinical features of PD was also investigated. Finally, we investigated the underlying mechanism of the association between pesticides and PD.

RESULTS

Serum levels of organochlorine pesticides, which included α-hexachlorocyclohexane (HCH), β-HCH, γ-HCH, δ-HCH, propanil, heptachlor, dieldrin, hexachlorobenzene, p,p'-dichlorodiphenyltrichloroethane and o,p'-dichloro-diphenyl-trichloroethane were higher in PD patients than controls. Moreover, α-HCH and propanil levels were associated with PD. Serum levels of dieldrin were associated with Hamilton Depression Scale and Montreal Cognitive Assessment scores in PD patients. In SH-SY5Y cells, α-HCH and propanil increased level of reactive oxygen species and decreased mitochondrial membrane potential. Furthermore, propanil, but not α-HCH, induced the aggregation of α-synuclein.

CONCLUSIONS

This study revealed that elevated serum levels of α-HCH and propanil were associated with PD. Serum levels of dieldrin were associated with depression and cognitive function in PD patients. Moreover, propanil, but not α-HCH, induced the aggregation of α-synuclein. Further research is needed to fully elucidate the effects of pesticides on PD.

Exposure to pesticides or agroecological practices: suicidal ideation among peasant farmers in Brazil's semi-arid region

Health risks faced by peasant farmers may vary depending on the type of agriculture they practice. This study examined the association between suicide ideation and exposure to pesticides by comparing two groups of peasant farmers of both sexes living in the semi-arid region of the north of Minas Gerais, Brazil: exposed to pesticides and adopting agroecological practices without the use of pesticides. Group participants were selected using convenience sampling and data was collected using a previously validated questionnaire administered through face-to-face interviews. Bivariate analysis was performed, followed by logistic regression. A total of 547 peasant farmers were interviewed (311 in the group exposed to pesticides and 236 in the group adopting agroecological practices). Respondents from the group exposed to pesticides were more likely to report suicidal ideation (OR=2.30; 95%CI 1.16-4.56), harmful alcohol consumption (OR=2.30; 95%CI 1.18-4.48), and lifetime acute pesticide poisoning (OR=8.58; 95%CI 2.98-24.72). The findings suggest that agricultural practices that lead to chronic pesticide exposure are associated with a greater likelihood of suicide ideation, regardless of previous episodes of acute pesticide poisoning or harmful alcohol consumption.

Neurobehavioral anomalies in zebrafish after sequential exposures to DDT and chlorpyrifos in adulthood: Do multiple exposures interact?

A sequence of different classes of synthetic insecticides have been used over the past 70 years. Over this period, the widely-used organochlorines were eventually replaced by organophosphates, with dichlorodiphenyltrichloroethane (DDT) and chlorpyrifos (CPF) as the principal prototypes. Considerable research has characterized the risks of DDT and CPF individually, but little is known about the toxicology of transitioning from one class of insecticides to another, as has been commonplace for agricultural and pest control workers. This study used adult zebrafish to investigate neurobehavioral toxicity following 5-week chronic exposure to either DDT or CPF, to or their sequential exposure (DDT for 5 weeks followed by CPF for 5 weeks). At the end of the exposure period, a subset of fish were analyzed for brain cholinesterase activity. Behavioral effects were initially assessed one week following the end of the CPF exposure and again at 14 months of age using a behavioral test battery covering sensorimotor responses, anxiety-like functions, predator avoidance and social attraction. Adult insecticide exposures, individually or sequentially, were found to modulate multiple behavioral features, including startle responsivity, social approach, predator avoidance, locomotor activity and novel location recognition and avoidance. Locomotor activity and startle responsivity were each impacted to a greater degree by the sequential exposures than by individual compounds, with the latter being pronounced at the early (1-week post exposure) time point, but not 3-4 months later in aging. Social approach responses were similarly impaired by the sequential exposure as by CPF-alone at the aging time point. Fleeing responses in the predator test showed flee-enhancing effects of both compounds individually versus controls, and no additive impact of the two following sequential exposure. Each compound was also associated with changes in recognition or avoidance patterns in a novel place recognition task in late adulthood, but sequential exposures did not enhance these phenotypes. The potential for chemical x chemical interactions did not appear related to changes in CPF metabolism to the active oxon, as prior DDT exposure did not affect the cholinesterase inhibition resulting from CPF. This study shows that the effects of chronic adult insecticide exposures may be relevant to behavioral health initially and much later in life, and that the effects of sequential exposures may be unpredictable based on their constituent exposures.

Occupational exposure of rural workers to pesticides in a vegetable-producing region in Brazil

The health of family farmers is at risk due to occupational exposure to pesticides. The aims of the current study were to investigate the level of farmers' perception of risks associated with pesticide use and to assess their health condition based on biochemical and immunological tests. Family farmers living in a vegetable-producing region in Southern Brazil were selected to participate in the study. More than 70% of the family farmers were often exposed to more than one type of pesticides; 41.2% were intensively using several pesticides for more than one decade and 74.4% were not using personal protective equipment (PPE) at the time of pesticide handling due to low perception of the risks posed by these chemicals. Enzymatic analysis performed in participants' blood samples showed changes in catalase (CAT) and glutathione reductase (GR) activity, in lipid peroxidation (TBARS) and carbonylated protein levels, as well as in chemoattractant (IL-8) and anti-inflammatory (IL-10) interleukin expression. Low perception of health-related risks posed by pesticides can be attributed to factors such as low schooling and lack of information, which put farmers' health at risk, as evidenced by blood biochemical and immunological changes.

Associations of acetylcholinesterase inhibition between pesticide spray seasons with depression and anxiety symptoms in adolescents, and the role of sex and adrenal hormones on gender moderation

BACKGROUND

Cholinesterase inhibitor pesticides, especially organophosphates, are endocrine disruptors and a few existing studies have linked self-reports of exposure with increased depression and anxiety. Some evidence suggests that associations may be stronger in women, but the mechanism of this gender difference is unclear. We assessed whether acetylcholinesterase (AChE) inhibition between 2 time points (reflecting greater cholinesterase inhibitor exposure) during different agricultural seasons in the year was associated with anxiety/depression symptoms.

METHODS

We examined 300 adolescents (ages 11-17y, 51% female) living near agricultural settings in Ecuador (ESPINA study) twice in 2016: April and July-October. We assessed AChE activity (finger stick), estradiol, testosterone, dehydroepiandrosterone, cortisol (saliva) and anxiety and depression scales (CDI-2 and MASC-2).

RESULTS

The mean (SD) depression and anxiety scores were 52.8 (9.3) and 58.1 (9.6), respectively. The median (25th, 75th percentile) AChE change (July-October vs April) was -3.94% (-10.45%, 5.13%). For every 10% decrease in AChE activity, there was a 0.96 unit (95%CI: 0.01, 1.90) increase in depression symptoms and an OR of elevated depression score of 1.67 (1.04, 2.66). These associations were stronger in girls (OR=2.72 [1.23, 6.00]) than boys (1.18 [0.59, 2.37]). Adjustment for cortisol, testosterone and dehydroepiandrosterone reduced gender differences by 18-62%. No associations were observed with anxiety.

DISCUSSION

Inhibition of AChE activity at 2 points in time during different pesticide spray periods was associated with greater depression symptoms, affecting girls more than boys. Gender differences may be partly explained by endocrine disruption. These findings suggest that AChE inhibition may transiently affect the mood of adolescents.

Health problems in agricultural workers occupationally exposed to pesticides

Agricultural workers are susceptible to several health problems as a result of occupational exposure to toxic substances, especially pesticides. The aim of this review was to describe the health issues associated with occupational exposure to pesticides in agricultural workers. A descriptive study, in the form of an integrative literature review, was conducted based on articles retrieved from the LILACS, SciELO and PubMed databases, published between January 2015 and October 2018. The searches were conducted using the keywords "pesticides," "workers' health," "occupational exposure" and "agricultural workers." The study was guided by the following research question: what health problems do agricultural workers experience as a result of occupational exposure to pesticides? The screening process led to the selection of 35 studies performed in several countries and continents, all of which shed light on the vulnerability of agricultural workers, especially due to the misuse of personal protective equipment and lack of knowledge about the correct use of these devices. The studies investigated a variety of health issues, and most reported a positive association between these conditions, which include cancer, and the use of pesticides. Educational and preventive measures must be implemented to promote the health of rural workers. Furthermore, it is crucial that governments play an active role in these initiatives and provide alternatives to pesticides for pest control.

Multi-biomarker responses to pesticides in an agricultural population from Central Brazil

We evaluated farmworkers exposed to pesticides and individuals with no history of occupational exposure to pesticides. It was performed the comet assay to evaluate DNA damage. The immunophenotyping of TCD4⁺ lymphocyte subpopulations in peripheral blood was performed by flow cytometry. The single nucleotide polymorphisms (SNPs) in PON1, XRCC1, IL6, IL6R, TNF-α, and MIR137 genes were evaluated by real-time PCR. The exposed group was composed mostly by males (69.44%), with direct exposure to pesticides (56%) and with an average age range of 46 ± 13.89 years, being that 58.3% of farmworkers directly exposed to pesticides and reported the full use of personal protective equipment (PPE). DNA damage was greater in the exposed group (p < 0.05), reinforced by the use of PPE to denote a lower degree of DNA damage (p = 0.002). In this context, in the exposed group, we demonstrated that the use of PPE, age, gender and intoxication events were the variables that most contributed to increase DNA damage (p < 0.0001). Besides, the exposed group showed a significant increase in the subpopulations of T lymphocytes CD3⁺CD4⁺ (p < 0.05) and CD3⁺CD4⁺CD25⁺ (p < 0.0001) and a significant decrease in CD3⁺CD4⁺CD25^-FOXP3⁺ (p < 0.05). SNPs in the TNF-α (rs361525) gene presented a difference in the genotype distribution between the groups (p = 0.002). The genotype distribution of TNF-α (rs361525) was also positively correlated with the DNA damage of the exposed group (r = 0.19; p = 0.01), demonstrating a higher risk of DNA damage in the farmworkers presenting the A mutated allele. Our findings demonstrate that pesticides can exert various deleterious effects on human health by damaging the DNA as well as by influencing the immune system in the case of both direct or indirect exposure and these issues are associated to age, gender, intoxication and the nonuse of PPE.

Exercise attenuates the association between household pesticide exposure and depressive symptoms: Evidence from NHANES, 2005-2014

BACKGROUND

The effect of household pesticide exposure on depressive symptoms in the general population is underexplored, and the role of exercise in the association between pesticide exposure and depressive symptoms is unclear.

OBJECTIVE

The goals of this study are to examine whether the associations between household pesticide exposure and depressive symptoms exist in the general population, and whether exercise can attenuate these associations.

METHODS

We used data from the 2005-2014 National Health and Nutrition Examination Surveys (NHANES), including a total of 14708 US adult participants who were 20 years or older. Depressive symptoms were assessed using the Patient Health Questionnaire (PHQ-9). Exercise information on the recreational physical activity (RPA) and pesticide exposure were self-reported in an interview.

RESULTS

Participants with exposure of household pesticide had a higher odds ratio ([OR]; OR = 1.32, 95% confidence intervals [CI]: 1.12-1.56) for depressive symptoms, compared to those who had not been unexposed. A significant interaction between exercise and pesticide exposure on depressive symptoms was observed (P = 0.038). Stratified analysis showed that household pesticide exposure was associated with a 50% higher risk of depressive symptoms (OR = 1.50, 95% CI: 1.20-1.86) in the population with light RPA. However, we did not find a significant association in the group with moderate + vigorous RPA (P = 0.305).

CONCLUSION

This study further confirms that household pesticide exposure is associated with an elevated risk of depressive symptoms in the general population. More importantly, we for the first time reports that moderate + vigorous RPA attenuates the positive association between household pesticide exposure and depressive symptoms.

Increased risk of atherosclerosis associated with pesticide exposure in rural areas in Korea

Atherosclerosis is a progressive inflammation in systemic vessels, and pesticide exposure has been emerging as its risk factor. This cross-sectional study investigated the association between pesticide exposure and the risk of atherosclerosis in a rural population in Korea using carotid intima-media thickness (CIMT). This study used dataset from the baseline survey of the Korea Farmers Cohort Study between November 2005 and January 2008, and the final analysis included 477 participants. Well-structured questionnaires were used to estimate pesticide exposure. CIMT ≥ 0.9 mm was established for carotid atherosclerosis. Multiple logistic regression analyses were undertaken to evaluate the association between pesticide exposure and atherosclerosis, adjusting demographic and health-related confounders. Even after adjustments, the increased risk of atherosclerosis was significantly associated with pesticide exposure, such as a lifetime history of farming (odds ratio [OR] 3.25 95% confidence interval [CI] 1.51–6.98), a history of using pesticide (OR 3.42 95% CI 1.63–7.16), using pesticide 10 times or more annually (OR 2.55 95% CI 1.21–5.39), and higher cumulative exposure index level (OR 3.63 95% CI 1.65–7.97). Further prospective studies are required to elucidate effects of pesticide exposure on the risk of atherosclerosis.

Prenatal exposure to the pesticide metam sodium induces sensorimotor and neurobehavioral abnormalities in mice offspring

The present study has investigated developmental neurotoxicity of Metam sodium (MS), from gestational day 6 and throughout the gestation period until delivery. Therefore, mated female mice were orally exposed on a daily basis to 0 (control), 50, 100 or 150 mg of MS/kg of body weight and their standard fertility and reproductive parameters were assessed. The offspring were examined for their sensorimotor development, depression and cognitive performance. Our results showed that MS exposure during pregnancy led to one case of mortality, two cases of abortion and disturbed fertility and reproductive parameters in pregnant dams. In offspring, MS induced an overall delay in innate reflexes and sensorimotor performances. Furthermore, all prenatally treated animals showed an increased level of depression-like behavior as well as a pronounced cognitive impairment in adulthood. These results demonstrated that prenatal exposure to MS causes a long-lasting developmental neurotoxicity and alters a wide range of behavioral functions in mice.

Youth working in tobacco farming: effects on smoking behavior and association with health status

BACKGROUND

Cultivation of tobacco raises concerns about detrimental health and social consequences for youth, but tobacco producing countries only highlight economic benefits. We compared sociodemographic and health-related characteristics of school-age youth who worked and did not work in tobacco farming and assessed the effects on smoking behavior and health at 1 year.

METHODS

We used existing data collected in the province of Jujuy, Argentina where 3188 youth 13 to 17 years of age from a random middle school sample responded to longitudinal questionnaires in 2005 and 2006. Multivariate logistic regression models predicted association of tobacco farming work with health status and smoking behavior at 1 year.

RESULTS

22.8% of youth in the tobacco growing areas of the province were involved in tobacco farming. The mean age of initiation to tobacco farming was 12.6 years. Youth working in farming had higher rates of fair or poor versus good or excellent self-perceived health (30.3% vs. 19.0%), having a serious injury (48.5% vs. 38.5%), being injured accidentally by someone else (7.5% vs. 4.6%), being assaulted (5.5% vs. 2.6%), and being poisoned by exposure to chemicals (2.5% vs. 0.7%). Youth working in tobacco farming also had higher prevalence of ever (67.9% vs. 55.2%), current (48.0% vs. 32.6%) and established smoking (17.8% vs. 9.9%). In multivariate logistic regression models tobacco farming in 2005 was associated with significant increased reporting of serious injury (OR = 1.4; 95%CI 1.1-2.0), accidental injury by someone else (OR = 1.5; 95% 1.0-2.1), assault (OR = 2.2; 95% CI 1.3-3.8), and poisoning by exposure to chemicals (OR = 2.5; 95% CI 1.2-5.4). Tobacco farming in 2005 predicted established smoking 1 year later (OR = 1.5; 95% CI 1.1-2.0).

CONCLUSION

Youth who work in tobacco faming face a challenging burden of adversities that increase their vulnerability. Risk assessments should guide public policies to protect underage youth working in tobacco farming. (298 words).

Doctors experiences on the quality of care for pesticide poisoning patients in hospitals in Kampala, Uganda: a qualitative exploration using donabedian's model

BACKGROUND

Pesticides are responsible for a significant percentage of deaths globally with majority occurring in sub-Saharan Africa. Deaths due to pesticide poisoning can be reduced if poisoning cases are managed optimally. However, the quality of care given to pesticide poisoning patients is still insufficient especially in sub-Saharan Africa. This study was aimed at exploring doctors' experiences on quality of care for pesticide poisoning cases in hospitals in Kampala, Uganda.

METHODS

Fifteen (15) in-depth interviews were conducted with doctors who were directly involved in management of pesticide poisoning patients in the accident and emergency, Medicine, Pediatrics and Intensive Care Unit wards in 5 hospitals in Kampala, Uganda. All interviews were transcribed and subjected to directed content analysis with the guidance of the Donabedian model of quality of care which emphasizes structure, process and outcome measures as pertinent to ensuring quality of care.

RESULTS

Doctors reported structural, process and outcome facets that support diagnosis and treatment of pesticide poisoning cases that improved the quality of care they provided. Among the structures includes hospital units such as Intensive Care Unit (ICU), pediatrics and internal medicine; equipment and clinical guidelines such as airway, breathing and consciousness (ABC) protocol; and doctors' knowledge and experiences. Doctors relied on history, and signs and symptoms to establish the cause and severity of pesticide poisoning. However, some patients and caretakers provided inaccurate pesticide poisoning history. Due to its availability in hospitals, doctors largely relied on atropine to manage pesticide poisoning cases whether or not relevant to treat the actual pesticide active ingredient responsible for the poisoning. Although majority of the cases treated recovered, those due to suicide were further referred to the hospital psychiatrist. Sharing experiences of managing pesticide poisoning patients among health workers and engaging in sensitization outreaches against pesticide poisoning were reported as potential activities to improve quality of care for pesticide poisoning patients.

CONCLUSION

Doctors reflected on the structure, process and outcome measures of quality of care given to pesticide poisoning patients. The implications of hospital structures and clinical process to the quality of the outcomes of care demonstrates their importance in improving management of pesticide poisoning cases in hospitals in Kampala, Uganda.

Key Risk Factors Affecting Farmers' Mental Health: A Systematic Review

Recently, concern has increased globally over farmers' mental health issues. We present a systematic review of the outcomes, locations, study designs, and methods of current studies on farmers' mental health. In particular, this review aims to fill an important gap in understanding of the potential key risk factors affecting farmers' mental health around the world. 167 articles on farmer mental health were included in a final systematic review using a standardized electronic literature search strategy and PRISMA guidelines. The four most-cited influences on farmers' mental health in the reviewed literature respectively were pesticide exposure, financial difficulties, climate variabilities/drought, and poor physical health/past injuries. The majority of studies were from developed countries, most specifically from the United States, Australia, and the United Kingdom. Comparative studies on the mental health of farmers and other occupational workers showed mixed results, with a larger portion identifying that psychological health disturbances were more common in farmers and farm-workers. Knowledge of farmer psychological disorder risk factors and its impacts are essential for reducing the burden of mental illness. Further research will be required on climate change impacts, developing country farmers' mental health, and information on how to reduce help-seeking barriers amongst farmers.

Microbiota and organophosphates

Organophosphates (OPs) are important toxic compounds commonly used for a variety of purposes in agriculture, industry and household settings. Consumption of these compounds affects several central nervous system functions. Some of the most recognised consequences of organophosphate pesticide exposure in humans include neonatal developmental abnormalities, endocrine disruption, neurodegeneration, neuroinflammation and cancer. In addition, neurobehavioral and emotional deficits following OP exposure have been reported. It would be of great value to discover a therapeutic strategy which produces a protective effect against these neurotoxic compounds. Moreover, a growing body of preclinical data suggests that the microbiota may affect metabolism and neurotoxic outcomes through exposure to OPs. The human gut is colonised by a broad variety of microorganisms. This huge number of bacteria and other microorganisms which survive by colonising the gastrointestinal tract is defined as "gut microbiota". The gut microbiome plays a profound role in metabolic processing, energy production, immune and cognitive development and homeostasis. The effects are not only localized in the gut, but also influence many other organs, such as the brain through the microbiome-gut-brain axis. Therefore, given the gut microbiota's key role in host homeostasis, this microbiota may be altered or modified temporarily by factors such as antibiotics, diet and toxins such as pesticides. The aim of this review is to examine scientific articles concerning the impact of microbiota in OP toxicity. Studies focussed on the possible contribution the microbiota has on variable host pharmacokinetic responses such as absorption and biotransformation of xenobiotics will be evaluated. Microbiome manipulation by antibiotic or probiotic administration and faecal transplantation are experimental approaches recently proposed as treatments for several diseases. Finally, microbiota manipulation as a possible therapeutic strategy in order to reduce OP toxicity will be discussed.

Association Between Chronic Exposure to Pesticide and Suicide

OBJECTIVE

We investigated the association between suicide and pesticide exposure in a community-based cohort study.

METHODS

We performed a longitudinal analysis of 6333 who participated in the initial survey of the Korean Genome and Epidemiology Study. Data were collected using a questionnaire to assess the prevalence of suicide. We calculated the hazard ratios (HRs) for suicide by pesticide exposure using the Cox proportional hazard model.

RESULTS

After adjusting for variables, participants exposed to pesticides had a 1.88-fold increased risk of suicide (HR, 1.88; 95% confidence interval [CI], 1.11 to 3.16) than those who were not exposed. Study populations with greater pesticide use (HR, 2.42; 95% CI, 1.27 to 4.60) and pesticide addiction had the highest suicide rates (HR, 1.91; 95% CI, 1.03 to 3.56).

CONCLUSIONS

Pesticide exposure for suicide should be considered during the development and implementation of suicide prevention in rural area.

Environmental Exposures and Depression: Biological Mechanisms and Epidemiological Evidence

Mental health and well-being are consistently influenced—directly or indirectly—by multiple environmental exposures. In this review, we have attempted to address some of the most common exposures of the biophysical environment, with a goal of demonstrating how those factors interact with central structures and functions of the brain and thus influence the neurobiology of depression. We emphasize biochemical mechanisms, observational evidence, and areas for future research. Finally, we include aspects of contextual environments—city living, nature, natural disasters, and climate change—and call for improved integration of environmental issues in public health science, policies, and activities. This integration is necessary for reducing the global pandemic of depression.

Pesticide exposure and cognitive decline in a rural South Korean population

We aimed to investigate the relationship between pesticide exposure and cognitive decline in a rural South Korean population. From July 2015 to December 2017, 200 randomly selected Korean Farmers Cohort study participants were recruited and of these, 169 participants were analyzed. Pesticide exposure was investigated using a standardized questionnaire, and the Korean-Montreal Cognitive Assessment (K-MoCA) was conducted. Cognitive decline was more frequent among those directly exposed to pesticides (P = 0.057). Pesticide exposure and cognitive decline were positively correlated in the group with direct exposure versus no exposure (crude odds ratio [OR], 2.66; 95% confidence interval [CI], 1.17–6.04); this relationship was insignificant after adjustment (adjusted OR, 1.50; 95% CI, 0.57–3.92). There was a significant difference in the K-MoCA scores for each group based on pesticide exposure (P = 0.003). When we stratified by age, differences in the K-MoCA scores depending on the degree of pesticide exposure in the those aged 60 to 69 years were identified. Overall, there was a tendency towards an association between pesticide exposure and cognitive decline in rural Korean adult farmers. In our study, chronic pesticide exposure tended to have a greater impact in certain age group (60–69 years) than in those under 60 and over 70.

Association between pesticide exposure intensity and self-rated health among greenhouse vegetable farmers in Ningxia, China

Background

Self-rated health (SRH) has been shown to be a stronger comprehensive predictor of health status than the clinical record. Although an association between specific pesticide exposures and health conditions has been reported in different populations, data on the relationship between pesticides exposure intensity (PEI) and SRH in greenhouse farmers is scarce. The aim of the current study was to evaluate this association among vegetable greenhouse farmers in Yinchuan City, western China.

Methods

Three consecutive cross-sectional studies were conducted in the years 2015, 2016 and 2017. Face-to-face interviews by trained investigators, using questionnaires, were performed. PEI was calculated by a validated method and then categorized into high, middle and low groups. SRH was measured via a single ten-point scale question and then divided into excellent (score >5) and poor SRH (score ≤5). A multivariable logistic regression model was used to evaluate the association. Meanwhile, the dose-response and interaction effects were estimated.

Results

A steady association between high PEI and poor SRH (OR: 1.55, 95% CI: 1.05–2.28 in the full model) was identified. Although high PEI was significantly associated with poor SRH in males and the Han ethnicity group, no significant association was found with poor SRH in females or those of Hui ethnicity. Interaction effects of education level and frequency of breakfast with PEI were determined (P_interaction = 0.04 and 0.02, respectively); synergistic enhanced effects for poor SRH were observed.

Conclusion

These findings indicate that high PEI might be associated with poor SRH among vegetable greenhouse farmers. A lower education level and never eating breakfast contributed to an increased likelihood of poor SRH in those with high PEI. The local government should be making great efforts to promote healthy behaviors and improve protection awareness.

Exposure to pesticides and the prevalence of diabetes in a rural population in Korea

BACKGROUND

Among the adverse health effects of exposure to pesticides, an association with diabetes has been reported. However, there is a lack of epidemiologic studies on the health effects of exposure to pesticides, particularly investigating the association between occupational pesticide exposure and diabetes prevalence.

PURPOSE

The present study examined the association between pesticide exposure and prevalence of diabetes in a rural population in Korea.

METHODS

This cross-sectional study used data from the Korea Farmers Cohort study, and included 2559 participants in the baseline survey between November 2005 and January 2008. We performed a clinical examination including blood sampling and assessed data on diabetes diagnosis, demographics, and pesticide exposure. Logistic regression was performed to evaluate the association between pesticide exposure and diabetes prevalence, adjusting for age, sex, monthly income, and marital status. In addition, a stratified analysis by body mass index (BMI) was conducted, with two categories: normal weight (<25 kg/m²) and overweight or obese (≥25 kg/m²).

RESULTS

At baseline, the prevalence of diabetes was 9.30%. Pesticide exposure was associated with the risk of diabetes after adjustment for covariates. In the analysis stratified by BMI, all the variables related to pesticide exposure were associated with prevalence of diabetes in the overweight or obese group, whereas no significant association was found in the normal weight group.

CONCLUSION

Exposure to pesticides was associated with diabetes, and this association was stronger in overweight or obese individuals than in normal weight individuals. Further longitudinal studies that consider information on BMI are necessary.

Assessment of Pesticide-Related Pollution and Occupational Health of Vegetable Farmers in Benguet Province, Philippines

BACKGROUND

Agriculture accounts for 20% of the national income in the Philippines. In order to boost agricultural activity and prevent crop damage, farmers rely on pesticides for vector control and management.

OBJECTIVES

The present study assessed the pesticide exposure and occupational health of agricultural farmers in the Philippines. The study site is one of the largest vegetable-producing provinces in the Philippines.

METHODS

This study employed both a survey questionnaire and physical health assessment, including a mental state examination. Pesticide exposure was estimated based on the duration of pesticide use, as well as the amount per spray application. The data results were segregated by gender, as women are also heavily engaged in agriculture in this part of the Philippines.

RESULTS

The results showed that pesticide exposure usually occurred during agricultural activities such as spray applications in the field (63.7%), mixing (38.4%), loading (34.1%) and field re-entry (9.7%). The most frequently used pesticides were Tamaron, Selecron, and Dithane. The mean duration of pesticide exposure was 14.23 years for males and 15.4 years for females. The longest used pesticide among males was Sumicidine (16.2 years), and Tamaron for females (18 years). In terms of amount used, the average was 147 ml per spray application for males and 65.5 ml for females. Exposure to pesticides was expressed in number of years and amount used per spray application, and the average exposure of males was 2,024.43 ml/years and 993.55 ml/years for females. Among farmers, 49% complained of being sick due to their work. Of those who became ill, a large percentage (69.8%) did not receive any medical attention. The most prevalent health symptoms were muscle pains (63.3%), muscle weakness (55%), and easy fatigability (52.4%). For the mini-mental state examination, abnormalities were found in 5.4% of males and 13.3% of females. The use of insecticides was associated with weakness, easy fatigability and weight loss.

DISCUSSION

The present study demonstrated frequent and significant duration of pesticide use among farmers in Benguet province, Philippines.

CONCLUSIONS

Pesticide exposure was considerable among the farmers in the present study. The occupational health conditions reported by the study subjects can be linked to their pesticide use. Although this study assessed risk factors associated with general health symptoms, further investigation is needed to determine specific pesticide exposure-health correlations.

PARTICIPANT CONSENT

Obtained.

ETHICS APPROVAL

The study was approved by the Research Ethics Board of the University of the Philippines, Manila, which is recognized and accredited by the Forum for Ethical Review Committees in Asia and the Western Pacific (FERCAP).