Pesticide exposure and self-reported incident depression among wives in the Agricultural Health Study

Neurotoxicity of glyphosate: Focus on molecular mechanisms probably associated with alterations in cognition and behavior

In recent decades, glyphosate and glyphosate-based herbicides (GBH) have been extensively used in agriculture all over the world. Initially, they were considered safe, but rising evidence suggests that these molecules reach the central nervous system producing metabolic, functional, and permanent alterations that impact cognition and behavior. This theoretical and non-systematic review involved searching, integrating, and analyzing preclinical evidence regarding the effects of acute, sub-chronic, and chronic exposure to glyphosate and GBH on cognition, behavior, neural activity, and development in adult and juvenile rodents following perinatal exposition. In addition, this review gathers the mechanisms underlying the neurotoxicity of glyphosate mediating cognitive and behavioral alterations. Furthermore, clinical evidence of the effects of exposition to GBH on human health and its possible link with several neurological disorders was revised.

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.

Association between glyphosate exposure and cognitive function, depression, and neurological diseases in a representative sample of US adults: NHANES 2013-2014 analysis

Glyphosate, the most widely used herbicide globally, has been linked to neurological impairments in some occupational studies. However, the potential neurotoxic effects of glyphosate exposure in the general population are still not fully understood. We conducted analyses on existing data collected from 1532 adults of the 2013-2014 National Health and Nutrition Examination Survey (NHANES) to explore the possible relationship between glyphosate exposure and cognitive function, depressive symptoms, disability, and neurological medical conditions. Our results showed a significant negative association between urinary glyphosate levels and the Consortium to Establish a Registry for Alzheimer's Disease Word List Memory Test (CERAD-WLT) trial 3 recall and delayed recall scores in both models, with ß coefficients of -0.288 (S.E. = 0.111, P = 0.021) and -0.426 (S.E. = 0.148, P = 0.011), respectively. Furthermore, the odds ratio did not show a significant increase with the severity of depressive symptoms with a one-unit increase in ln-glyphosate levels. However, the odds ratio for severe depressive symptoms was significantly higher than for no symptoms (odds ratio = 4.148 (95% CI = 1.009-17.133), P = 0.049). Notably, the odds ratio showed a significant increase for individuals with serious hearing difficulty (odds ratio = 1.354 (95% CI = 1.018-1.800), P = 0.039) with a one-unit increase in ln-glyphosate levels, but not for other neurological medical conditions. In conclusion, our findings provide the first evidence that glyphosate exposure may be associated with neurological health outcomes in the US adult population. Additional investigation is necessary to understand the potential mechanisms and clinical significance of these correlations.

High pesticide exposures events, pesticide poisoning, and shingles: A medicare-linked study of pesticide applicators in the agricultural health study

OBJECTIVES

Self-reported shingles was associated with history of high pesticide exposure events (HPEE) in licensed pesticide applicators aged >60 years in the Agricultural Health Study (AHS). In the current study, using AHS-linked Medicare claims data, we examined incident shingles in relation to pesticide-related illness and pesticide poisoning, as well as HPEE.

METHODS

We studied 22,753 licensed private pesticide applicators (97% white males, enrolled in the AHS 1993-97), aged ≥66 years with >12 consecutive months of Medicare fee-for-service hospital and outpatient coverage between 1999 and 2016. Incident shingles was identified based on having ≥1 shingles claim(s) after 12 months without claims. At AHS enrollment, participants were asked if they ever sought medical care or were hospitalized for pesticide-related illness, and a supplemental questionnaire (completed by 51%) asked about HPEE and poisoning. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated using Cox proportional hazards regression, adjusted for age, sex, race, state, and education.

RESULTS

Over 192,053 person-years (PY), 2396 applicators were diagnosed with shingles (10.5%; age-standardized rate, 13.6 cases per 1,000PY), with higher rates among those reporting hospitalization for pesticide-related illness, pesticide poisoning, and HPEE (23.2, 22.5, and 16.6 per 1,000PY, respectively). In adjusted models, shingles was associated with hospitalization for pesticide-related illness (HR 1.69; 1.18, 2.39), poisoning (1.49; 1.08, 1.46), and HPEE (1.23; 95% CI = 1.03, 1.46), especially HPEE plus medical care/poisoning (1.78; 1.30, 2.43).

CONCLUSION

These novel findings suggest that acute, high-level, and clinically impactful pesticide exposures may increase risk of shingles in subsequent years to decades following exposure.

Anxiety and Associated Stressors Among Farm Women in England and Wales

OBJECTIVES

The findings presented here derive from a wider study that sought to establish a baseline understanding of mental health and wellbeing among the agricultural community in England and Wales. This paper focuses on selected questions that investigated levels of anxiety and associated stress factors among farm women, a group which has been relatively neglected within previous research on farming mental health in the United Kingdom.

METHODS

A questionnaire survey was widely distributed to members of the agricultural community in England and Wales (n = 15,296) in both paper and online formats. The survey included a number of standardised instruments to assess mental health and wellbeing, including the Generalised Anxiety Disorder-7 scale (GAD-7). Focusing on a sub-sample of female respondents (n = 3487), this paper details the findings from the GAD-7, alongside those from a selection of other questions investigating sources of stress, loneliness and perceived business viability.

RESULTS

A significant proportion of female respondents were experiencing anxiety at the time of survey completion, with 23.3% reaching the threshold for clinically relevant anxiety based on their GAD-7 scores (medium or severe anxiety, scores≥10). A further 34.6% were classified as experiencing mild anxiety (scores 5-9) whilst 42.1% were not suffering from anxiety (scores 0-4). Medium/severe anxiety was identified as being associated with a number of stress factors, feelings of loneliness and pessimistic perceptions of farm business viability. There were important age-based differences, with working-aged women identified as more likely to suffer from anxiety, loneliness and certain stressors than older women.

CONCLUSION

The findings reported here indicate concerning levels of anxiety among farming women and this should be seen as a call to action. There are clear associations between anxiety and a range of stressors and, although we cannot ascertain causality, these point to issues that demand attention in efforts to improve mental health within this social group. The factors contributing to anxiety are, however, multiple and complex and farm women may be affected by particular gender-based challenges that have not yet been explicitly explored in relation to mental health. Further research is needed to investigate and understand these issues in greater depth.

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.

Psychological Morbidity in the Farming Community: A Literature Review

The mental health of the farming community across industrialised nations has long been a major concern. Using an adapted procedure for a systematic literature review of observational epidemiological studies reporting prevalence (informed by the Joanna Briggs Institute method), this paper reviews peer-reviewed literature that explicitly compares farmer and non-farmer mental health (n = 48). In doing so, it provides a central and accessible evidence base for researchers and practitioners, and simultaneously reveals a stark lack of consensus; specifically, 54.0% of measures deployed to assess farmer mental health determined it to be the same as or even better than non-farming populations. This ambiguity sits in sharp contrast to the unequivocally worrisome farmer suicide statistics. Informed by the literature, the paper discusses potential reasons for this mismatch, including (i) farmers' progression through a different "pathway" to suicide that is not always preceded by mental illness, and (ii) a failure of current methods to accurately gauge the mental health status of farmers. The paper concludes by recommending more research into farmers' "pathway" to suicide, and highlights the need for a dedicated and multi-disciplinary programme of methods research that will afford a more culturally appropriate and effective means of understanding mental health in the farming community.

Systematic literature review of the epidemiology of glyphosate and neurological outcomes

PURPOSE

Human health risk assessments of glyphosate have focused on animal toxicology data for determining neurotoxic potential. Human epidemiological studies have not yet been systematically reviewed for glyphosate neurotoxicity hazard identification. The objective of this systematic literature review was to summarize the available epidemiology of glyphosate exposure and neurological outcomes in humans.

METHODS

As of December 2021, 25 eligible epidemiological studies of glyphosate exposure and neurological endpoints were identified and assessed for five quality dimensions using guidance from the U.S. Environmental Protection Agency. Studies that assessed personal use of glyphosate were prioritized, whereas those assessing indirect exposure (other than personal use) were rated as low quality, since biomonitoring data indicate that indirect metrics of glyphosate exposure almost always equate to non-detectable glyphosate doses.

RESULTS

Overall, the scientific evidence on glyphosate and neurotoxicity in humans is sparse and methodologically limited, based on nine included epidemiological studies of neurodegenerative outcomes (two high quality), five studies of neurobehavioral outcomes (two high quality), six studies of neurodevelopmental outcomes (none high quality), and five studies of other and mixed neurological outcomes (one high quality). The five high-quality studies showed no association between glyphosate use and risk of depression, Parkinson disease, or peripheral nerve conduction velocity. Results were mixed among the eight moderate-quality studies, which did not demonstrate consistent associations with any neurological endpoints or categories. Low-quality studies were considered uninformative about possible neurotoxic effects due primarily to questionable assessments of indirect exposure.

CONCLUSIONS

No association has been demonstrated between glyphosate and any neurological outcomes in humans. To move the state of science forward, epidemiological studies should focus on scenarios involving direct and frequent use of glyphosate while collecting information on validated health outcomes, concomitant agricultural exposures, and relevant personal characteristics.

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

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

Association between serum pyrethroid insecticide levels and incident type 2 diabetes risk: a nested case-control study in Dongfeng-Tongji cohort

Pyrethroid insecticides have been extensively used worldwide, but few studies explored the prospective association between pyrethroid exposure and incident type 2 diabetes (T2D). We conducted a nested case-control study of 2012 paired cases and controls, and measured eight pyrethroid insecticides in the baseline sera. We used conditional logistic regression models to estimate odds ratios (ORs) with 95% confidence intervals, and constructed multiple-pollutant models to investigate the association of pyrethroid mixture with incident T2D risk. The median concentrations (detection rates) were 3.53 μg/L (92.45%), 0.52 μg/L (99.80%), 1.16 μg/L (90.61%) and 1.43 μg/L (99.95%) for permethrin, cypermethrin, fenvalerate, and deltamethrin, respectively. Compared to participants with serum fenvalerate levels in the first quartile, the multivariable-adjusted ORs of incident T2D were 1.20 (95% CI 0.86-1.67), 1.41 (0.97-2.05), and 2.29 (1.27-4.11) for the second, third and fourth quartile (P trend = 0.01). Spline analysis further confirmed the positive association between serum fenvalerate levels and incident T2D risk (P for overall association = 0.006). Furthermore, mixture models revealed a positive association of pyrethroid mixture with incident T2D risk, with serum fenvalerate ranked as the top contributor (proportion of relative contribution: > 70%). We found that high concentrations of serum pyrethroid insecticides were significantly associated with an increased risk of incident T2D. The elevated risk was largely explained by fenvalerate. Further investigations are urgently needed to confirm our findings and elucidate the underlying mechanisms, given the widespread use of pyrethroids and the global pandemic of diabetes.

Health-related quality of life within agriculture in England and Wales: results from a EQ-5D-3L self-report questionnaire

BACKGROUND

Mental and physical health problems among the farming community are well documented but there is limited evidence regarding the overall health status of this population. This paper offers a unique insight into this issue through presenting the findings from a survey instrument, the EQ-5D-3L, which provides a standardised measure of health-related quality of life (HRQOL).

METHODS

We conducted the largest ever survey (n = 15,296) of people living and working in agriculture in England and Wales to gather baseline data on health and wellbeing within this community. The survey included an assessment of HRQOL through the use of the EQ-5D-3L self-report questionnaire. A variety of statistical approaches were used to test for significant associations between HRQOL and sub-group characteristics, including the Chi-square test for independence, the Kruskal-Wallis test, and Mann-Whitney U-test. Binary logistic regression models were also created to assess the influence of a set of respondent characteristics on the likelihood of respondents reporting health problems in the EQ-5D-3L.

RESULTS

24% of respondents reported problems with mobility; 4% reported problems with self-care; 21% reported problems with performing their usual activities; 52% reported problems with pain/discomfort; and 31% reported problems with anxiety/depression. The mean EQ-5D index value was 0.811 (median (Md) 0.796, interquartile range (IQR) 0.275). The mean self-rated health score (EQ-VAS) was 77.6 (SD 16.1) (Md 80.0, IQR 20). In general, holding other respondent characteristics equal, women reported fewer problems with mobility, self-care, performing usual activities and pain/discomfort than men, but more problems with anxiety/depression. HRQOL in the working-aged appears to be poorer among the survey population than the wider UK population.

CONCLUSIONS

Results reveal concerning levels of physical and mental health problems, especially pain/discomfort and anxiety/depression, which appear to be more prevalent within our sample than within the wider UK population. There were important gender and age-related differences in both mental and physical health. Combatting these problems through targeted support is essential for the wellbeing of the farming community and the future sustainability of UK food production.

Glyphosate and neurological outcomes: A systematic literature review of animal studies

Studies of nervous system effects of glyphosate, a widely used herbicide, have not been critically examined. The aim of this paper was to systematically review glyphosate-induced neurotoxicity literature to determine its usefulness in regulatory decision-making. The review was restricted to mammalian studies of behavior, neuropathology, and neuropharmacology; in vitro and other biochemical studies were considered supplementary information. Glyphosate formulation studies were also considered, despite uncertainties regarding toxicities of the formulated products; no studies used a formulation vehicle as the control. Inclusion criteria were developed a priori to ensure consistent evaluation of studies, and in vivo investigations were also ranked using ToxRTool software to determine reliability. There were 27 in vivo studies (open literature and available regulatory reports), but 11 studies were considered unreliable (mostly due to critical methodological deficiencies). There were only seven acceptable investigations on glyphosate alone. Studies differed in terms of dosing scenarios, experimental designs, test species, and commercial product. Limitations included using only one dose and/or one test time, small sample sizes, limited data presentation, and/or overtly toxic doses. While motor activity was the most consistently affected endpoint (10 of 12 studies), there were considerable differences in outcomes. In six investigations, there were no marked neuropathological changes in the central or peripheral nervous system. Other neurological effects were less consistent, and some outcomes were less convincing due to influences including high variability and small effect sizes. Taken together, these studies do not demonstrate a consistent impact of glyphosate on the structure or function of the mammalian nervous system.

Global burden of mental illness in agents fighting endemics

Abstract: Mental disorders are the main cause of the young and economically active population worldwide and in Brazil to live with disabilities, being an important public health problem nowadays. The objective was to estimate the burden of mental disorders among professionals working to combat endemic diseases in a state in northeastern Brazil. Medical records of workers linked to the Brazilian Ministry of Health in Ceará State and fighting endemic diseases were surveyed and, from this, a historical cohort was made. The individual quantification of absenteeism by mental disorders (ICD F-chapter referring to mental disorders) was conducted considering a period of about 35 years, from admission (the 1980s) to December 2017. The global burden of disease was measured by the YLD indicator (years lost to disability). Considering that no deaths due to mental disorders were observed, the YLL indicator (years of life lost) was composed. The high mental disorders burden in this group of workers stands out, whose mood disorders, including depression, conferred a YLD equal to 18.6. This represents just over 18 years of work lived with a disability. Our findings reinforce the need to implement surveillance and health promotion actions in workers to promote effective interventions capable of contributing to the reduction of morbidity in workers and economically active people.

Self-reported psychological distress and self-perceived health in residents living near pesticide-treated agricultural land: a cross-sectional study in The Netherlands

OBJECTIVES

There is rising concern regarding possible health effects from exposure to pesticides in residents living near agricultural land. Some studies indicated increased risks of reporting symptoms of anxiety and depression among agricultural workers but less is known about the mental and perceived health of rural residents. We aimed to study possible associations between self-reported psychological distress (SPD) and self-perceived health (SPH) in residents near pesticide-treated agricultural land.

METHODS

Using the Public Health Monitor national survey from 2012, we selected 216 932 participants who lived in rural and semi-urban areas of the Netherlands and changed addresses at most once in the period 2009-2012. Psychological distress (PD) was assessed via the Kessler Psychological Distress scale (K10) and participants were asked to assess their own health. We estimated the area of specific crop groups cultivated within buffers of 50 m, 100 m, 250 m and 500 m around each individual's residence for the period 2009-2012. Association between these exposure proxies and the outcomes was investigated using logistic regression, adjusting for individual, lifestyle and area-level confounders.

RESULTS

Overall, results showed statistically non-significant OR across all buffer sizes for both SPD and SPH, except for the association between SPH and 'all crops' (total area of all considered crop groups) with OR (95% CI) ranging from 0.77 (0.63 to 0.93) in 50 m to 1.00 (1.00 to 1.00) in 500 m. We observed that most ORs were below unity for SPH.

CONCLUSIONS

This study provides no evidence that residential proximity to pesticide treated-crops is associated with PD or poorer perceived health.

Long-Term Neurological and Psychological Distress Symptoms among Smallholder Farmers in Costa Rica with a History of Acute Pesticide Poisoning

Studies suggest that acute pesticide poisonings (APP) may be linked with long-term neurological effects. To examine long-term neurological and psychological distress symptoms associated with having experienced an APP, we conducted a cross-sectional study of 300 conventional and organic smallholder farmers from Zarcero County, Costa Rica, May–August 2016. We collected self-reported data on sociodemographic characteristics, occupational history, pesticide exposure, APPs, neurological and psychological distress symptoms (using the Brief Symptom Inventory (BSI)). Adjusted logistic regression models were fit. A total of 14% of the farmers (98% male) reported experiencing at least one APP during their lifetime. Self-reported APP was associated with neurological symptoms during the 12 months prior to interview (e.g., fainting (Odds Ratio: 7.48, 95% Confidence Interval: 1.83, 30.74), shaking hands (3.50; 1.60, 7.60), numbness/tingling in hands or feet (3.23; 1.66, 6.32), insomnia (2.53; 1.34, 4.79), accelerated heartrate (2.42; 1.03, 5.47), dizziness (2.38; 1.19, 4.72), increased irritability/anger (2.37; 1.23, 4.55), low energy (2.33; 1.23, 4.46), and difficulty concentrating (2.01; 1.05, 3.85)). Farmers who reported an APP in the ten years prior to interview experienced increased odds of abnormal BSI scores for hostility (4.51; 1.16, 17.70) and paranoid ideation (3.76; 0.99, 18.18). Having experienced an APP may be associated with long-term neurological and psychological distress symptoms.

A Scoping Review of Non-Occupational Exposures to Environmental Pollutants and Adult Depression, Anxiety, and Suicide

PURPOSE OF REVIEW

Despite a call for better understanding of the role of environmental pollutant influences on mental health and the tremendous public health burden of mental health, this issue receives far less attention than many other effects of pollutants. Here we summarize the body of literature on non-occupational environmental pollutant exposures and adult depression, anxiety, and suicide-in PubMed, Embase, Web of Science, and PsychINFO through the end of year 2018.

RECENT FINDINGS

One hundred twelve articles met our criteria for further review. Of these, we found 88 articles on depression, 33 on anxiety, and 22 on suicide (31 articles covered multiple outcomes). The earliest article was published in 1976, and the most frequent exposure of interest was air pollution (n = 33), followed by secondhand smoke (n = 20), metals (n = 18), noise (n = 17), and pesticides (n = 10). Other exposures studied less frequently included radiation, magnetic fields, persistent organic pollutants (POPs), volatile organic compounds, solvents, and reactive sulfur compounds. The current literature, although limited, clearly suggests many kinds of environmental exposures may be risk factors for depression, anxiety, and suicide. For several pollutants, important limitations exist with many of the studies. Gaps in the body of research include a need for more longitudinal, life-course studies, studies that can measure cumulative exposures as well as shorter-term exposures, studies that reduce the possibility of reverse causation, and mechanistic studies focused on neurotoxic exposures.

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.

Production of a specific monoclonal antibody for 1-naphthol based on novel hapten strategy and development of an easy-to-use ELISA in urine samples

1-naphthol (1-NAP) is the main metabolite of pesticide carbaryl and naphthalene, and is also a genotoxic and carcinogenic intermediate in the synthesis of organic compound, dyes, pigment and pharmaceutical industry. In this work, two novel haptens were designed and synthesized for developing a competitive indirect enzyme-linked immunosorbent assay (ciELISA) method for 1-NAP in urine samples. The assay showed a limit of detection of 2.21 ng/mL and working range from 4.02 ng/mL to 31.25 ng/mL for 1-NAP in optimized working buffer. The matrix effect of samples was eliminated via 15-fold dilution of optimized working buffer. Good average recoveries (102.4%-123.4%) with a coefficient of variation from 11.7% to 14.7% was obtained for spiked urine samples. Subsequent instrument verification test showed good correlation between the results of ciELISA and high-performance liquid chromatography. The developed ciELISA is a high-throughput tool to monitor 1-NAP in urine, which can provide technical support for the establishment of biological exposure level for the exposure to carbaryl, naphthalene and other related pollutants.

Mitochondrial respiratory chain complex I dysfunction induced by N-methyl carbamate ex vivo can be alleviated with a cell-permeable succinate prodrug

Human exposure to carbamates and organophosphates poses a serious threat to society and current pharmacological treatment is solely targeting the compounds' inhibitory effect on acetylcholinesterase. This toxicological pathway, responsible for acute symptom presentation, can be counteracted with currently available therapies such as atropine and oximes. However, there is still significant long-term morbidity and mortality. We propose mitochondrial dysfunction as an additional cellular mechanism of carbamate toxicity and suggest pharmacological targeting of mitochondria to overcome acute metabolic decompensation. Here, we investigated the effects on mitochondrial respiratory function of N-succinimidyl N-methylcarbamate (NSNM), a surrogate for carbamate insecticides, ex vivo in human platelets. Characterization of the mitochondrial toxicity of NSNM in platelets revealed a dose-dependent decrease in mitochondral oxygen consumption linked to respiratory chain complex I while the pathway through complex II was unaffected. In intact platelets, an increase in lactate production was seen, due to a compensatory shift towards anaerobic metabolism. Treatment with a cell-permeable succinate prodrug restored the NSNM-induced (100 μM) decrease in mitochondrial oxygen consumption and normalized lactate production to the level of control. We have demonstrated that carbamate-induced mitochondrial complex I dysfunction can be alleviated with a mitochondrial targeted countermeasure: a cell-permeable prodrug of the mitochondrial complex II substrate succinate.

Application, monitoring and adverse effects in pesticide use: The importance of reinforcement of Good Agricultural Practices (GAPs)

This review intends to integrate the relevant information that is related to pesticide applications in food commodities and will cover three main sections. The first section encompasses some of the guidelines that have been implemented on management of pesticide application worldwide, such as the establishment of a value called Maximum Residue Level (MRL) through the application of Good Agricultural Practices (GAPs) into daily agricultural activities. A brief overview of the methods adopted in quantification of these trace residues in different food samples will also be covered. Briefly, pesticide analysis is usually performed in two stages: sample preparation and analytical instrumentation. Some of the preparation methods such as QuEChERs still remain as the technique of choice for most of the analytical scientists. In terms of the instrumentation such as the gas chromatography-mass spectrophotometry (GC-MS) and high performance-liquid chromatography (HPLC), these are still widely used, in spite of new inventions that are more sustainable and efficient such as the capillary electrophoresis (CE). Finally, the third section emphasizes on how pesticides can affect our health significantly whereby different types of pesticides result in different adverse health implications, despite its application benefits in agriculture in controlling pests. To date, there are limited reviews on pesticide usage in many agricultural-based nations; for the purpose of this review, Malaysia is selected to better illustrate pesticide regulations and implementation of policies. Finally, the review aims to provide an insight on how implementation of GAP and food safety assurance are inter-related and with this established correlation, to identify further measures for improvement to enable reinforcement of optimised agricultural practices specifically in these countries.

Highly Sensitive Detection of Chemically Modified Thio-Organophosphates by an Enzymatic Biosensing Device: An Automated Robotic Approach

Pesticides represent some of the most common man-made chemicals in the world. Despite their unquestionable utility in the agricultural field and in the prevention of pest infestation in public areas of cities, pesticides and their biotransformation products are toxic to the environment and hazardous to human health. Esterase-based biosensors represent a viable alternative to the expensive and time-consuming systems currently used for their detection. In this work, we used the esterase-2 from Alicyclobacillus acidocaldarius as bioreceptor for a biosensing device based on an automated robotic approach. Coupling the robotic system with a fluorescence inhibition assay, in only 30 s of enzymatic assay, we accomplished the detection limit of 10 pmol for 11 chemically oxidized thio-organophosphates in solution. In addition, we observed differences in the shape of the inhibition curves determined measuring the decrease of esterase-2 residual activity over time. These differences could be used for the characterization and identification of thio-organophosphate pesticides, leading to a pseudo fingerprinting for each of these compounds. This research represents a starting point to develop technologies for automated screening of toxic compounds in samples from industrial sectors, such as the food industry, and for environmental monitoring.

Identification of markers of depression and neurotoxicity in pesticide exposed agriculture workers

Earlier, we reported that chronic exposure to pesticides causes a reduction in the acetylcholinesterase activity and hematological and biochemical alterations in agriculture workers. In continuation with that, the present study aimed to investigate the pesticide-induced neurochemical imbalance and its association with behavior alterations in agricultural workers. A significant increase in depressive symptoms, assessed by the Beck Depression Inventory-II was observed in pesticide exposed workers as compared to the unexposed. A decrease in the level of dopamine in plasma and levels of dopamine, 3,4-dihydroxyphenylacetic acid, homovanillic acids, norepinephrine, serotonin, and hydroxyindoleacetic acid in urine was also observed. An increase in the levels of MAO-A and MAO-B has also been observed in these individuals. The decreased levels of neurotransmitters in the blood and urine have been linked with increased levels of MAO and pesticide residues in plasma and urine. Furthermore, these changes were associated with a higher incidence of depression in agricultural workers.

Risk for Depressive Symptoms and Suicide Among U.S. Primary Farmers and Family Members: A Systematic Literature Review

Background: About 84% of the agriculture, fishing, and forestry occupational sector is comprised of farmers. This sector is at high risk for suicide in the United States. Recent disasters and trade upheavals may make farmers and their families more vulnerable to depression and suicide. This review focused on the risk for depression and suicide among United States’ primary farm operators and their families. Methods: A systematic search of the literature published between January 2000 and June 2019, using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology was conducted. Results: A total of 30 articles met full inclusion criteria. Seventeen reports emanated from the midwest. Twenty studies used a cross-sectional design, primarily assessing a convenience sample or random stratified sample from a limited geographic area. We discovered only one intervention evaluation study. Depressive symptoms were assessed as part of the studies, but it was not the major focus. A variety of instruments measured depressive symptoms, with the Centers for Disease Control Epidemiologic Studies—Depression (CES-D) Scale used more frequently than other scales. Thirteen studies focused on the relationship between pesticide/chemical exposure and depression or suicide risk. Increased stress, poor physical health, compromised financial position, and previous injury were among the leading indicators of depression. Conclusion/Application to Practice: The limited number of studies that was discovered identified the need for more robust science where the risk for depression and suicide is the primary focus of the study and for intervention studies grounded in science. Occupational health providers should be vigilant about farm exposure and be aware of factors that may influence depressive symptoms of workers who operate farm establishments.

Determination of Picomolar Concentrations of Paraoxon in Human Urine by Fluorescence-Based Enzymatic Assay

Organophosphate (OP) pesticides are widely used in the agricultural field and in the prevention of pest infestation in private and public areas of cities. Despite their unquestionable utility, several of these compounds demonstrate toxic effects to the environment and human health. In particular, the occurrence of some organophosphate pesticides is correlated to the incidence of nervous system disorders, especially in children. The detection of pesticide residues in the human body represents an important task to preserve human health. In our work we propose the use of esterase-based biosensors as a viable alternative to the expensive and time-consuming systems currently used for their detection in human fluids. Using the esterase-2 activity, coupled with a fluorescence inhibition assay, we are able to detect very low concentration levels of diethyl (4-nitrophenyl) phosphate (paraoxon) in the range of the femtomole (fmol). Method robustness tests indicate the stability of esterase-2 in a diluted solution of 4% human urine, and we are able to accurately determine concentration levels of paraoxon in the range from 0.1 to 2 picomoles (pmol). The system sensitivity for OP detection is calculated at 524 ± 14.15 fmol of paraoxon recognized at 10% of inhibition, with an estimated limit of quantification of 262 ± 8.12 pmol mL^-1. These values are comparable with the most recent analysis methods based on mass spectrometry carried out on human samples for pesticide detection. This research represents a starting point to develop cheap and fast testing methods for a rapid screening of toxic substances in human samples.

Comparison of Self-Rated Health among Characteristic Groups of Vegetable Greenhouse Farmers Based on Exposure to Pesticide Residuals: A Latent Profile Analysis

Objective

The current study was aimed at using a latent profile analysis (LPA) model to classify greenhouse farmers into a potential cluster according to their exposure to pesticide residuals. Further, the association between self-rated health (SRH) and the cluster exposed to pesticide residual was explored.

Methods

Four hundred sixty-four farmers from vegetable greenhouses were selected, their SRH information was gathered through questionnaires from the “Self-Rated Health Measurement Scale (SRHMS)” Version 1.0, and the corresponding pesticide residuals were detected in a laboratory. The linear mixed regression model was employed for association assessment.

Results

Two latent clusters were extracted as samples, and the results showed that a high amount of pesticide residual accounted for poor physical health, but did not show statistical significance. In addition, an inverse significant association was observed between psychosocial symptoms and negative emotion and pesticide residual level. Furthermore, a diversity of significant relationship was observed in social health and its corresponding dimensions with latent cluster.

Conclusions

LPA offers a holistic and parsimonious method to identify high-risk health clusters of greenhouse workers in various health aspects and allows for a personality-targeted intervention by a local health department.

Relationship between cumulative exposure to pesticides and sleep disorders among greenhouse vegetable farmers

Background

In the northern region of China, many greenhouse vegetable farmers are exposed to high cumulative levels of pesticides due to long-term work in greenhouses that impacts their health. The aim of the current study was to identify the relationship between cumulative pesticide exposure and sleep disorders among farmers in Yinchuan, Northwest China.

Methods

A cross-sectional study was conducted for 3 consecutive years in 2015, 2016 and 2017. Using a random sampling to select the resident teams, 1366 participants were enrolled, and information was collected via face-to-face interviews by trained investigators. Ordinal logistic, multinomial logistic and poisson logistic regression models were used to identify the associations between cumulative exposure intensity (CEI) and sleep disorders.

Results

High CEI (OR = 1.56, 95% CI: 1.02–3.38) was associated with short sleep duration when compared with low CEI in the Full Model. CEI was not associated with long sleep duration. Self-rated sleep quality was associated with medium (OR = 1.46, 95% CI: 1.10–2.00) and high (OR = 2.50, 95% CI: 1.83–3.40) CEI. Similarly, having difficulty sleeping was associated with medium (OR = 1.52, 95% CI: 1.02–2.24) and high (OR = 1.74, 95% CI: 1.16–2.62) CEI. Differences in the associations by gender were also noted.

Conclusion

CEI was associated with sleep disorders, and gender differences were observed. Efforts should be made by local governments to address sleep problems that result from cumulative pesticide exposure in farmers, and gender differences should be considered.

Electronic supplementary material

The online version of this article (10.1186/s12889-019-6712-6) contains supplementary material, which is available to authorized users.

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.

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.

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

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

Toxicological profile of organochlorines aldrin and dieldrin: an Indian perspective

Several epidemiological studies have suggested various environmental factors as a possible cause for increased incidence of various abnormalities. Of the various environmental contaminants, the most prevalent and the most discussed are the endocrine disrupting chemicals. Contact of such disruptors with humans has become inevitable today. They are cosmopolitan and present from agriculture to industrial sectors, even in day-to-day consumer products. Aldrin and dieldrin belong to one such class of substances which are known to have a toxic effect on various physiological systems of the human body. Despite an imposed ban on their manufacture and commercial use, these pesticides could still be detected in probable areas of consumption like agriculture. The present review discusses the known possible toxic effects of aldrin and dieldrin and their current existence in the ecosystem across India.

Assessing the Potential for Bias From Nonresponse to a Study Follow-up Interview: An Example From the Agricultural Health Study

Prospective cohort studies are important tools for identifying causes of disease. However, these studies are susceptible to attrition. When information collected after enrollment is through interview or exam, attrition leads to missing information for nonrespondents. The Agricultural Health Study enrolled 52,394 farmers in 1993-1997 and collected additional information during subsequent interviews. Forty-six percent of enrolled farmers responded to the 2005-2010 interview; 7% of farmers died prior to the interview. We examined whether response was related to attributes measured at enrollment. To characterize potential bias from attrition, we evaluated differences in associations between smoking and incidence of 3 cancer types between the enrolled cohort and the subcohort of 2005-2010 respondents, using cancer registry information. In the subcohort we evaluated the ability of inverse probability weighting (IPW) to reduce bias. Response was related to age, state, race/ethnicity, education, marital status, smoking, and alcohol consumption. When exposure and outcome were associated and case response was differential by exposure, some bias was observed; IPW conditional on exposure and covariates failed to correct estimates. When response was nondifferential, subcohort and full-cohort estimates were similar, making IPW unnecessary. This example provides a demonstration of investigating the influence of attrition in cohort studies using information that has been self-reported after enrollment.

Organic solvent exposure and depressive symptoms among licensed pesticide applicators in the Agricultural Health Study

PURPOSE

Although organic solvents are often used in agricultural operations, neurotoxic effects of solvent exposure have not been extensively studied among farmers. The current analysis examined associations between questionnaire-based metrics of organic solvent exposure and depressive symptoms among farmers.

METHODS

Results from 692 male Agricultural Health Study participants were analyzed. Solvent type and exposure duration were assessed by questionnaire. An "ever-use" variable and years of use categories were constructed for exposure to gasoline, paint/lacquer thinner, petroleum distillates, and any solvent. Depressive symptoms were ascertained with the Center for Epidemiologic Studies Depression Scale (CES-D); scores were analyzed separately as continuous (0-60) and dichotomous (<16 versus ≥16) variables. Multivariate linear and logistic regression models were used to estimate crude and adjusted associations between measures of solvent exposure and CES-D score.

RESULTS

Forty-one percent of the sample reported some solvent exposure. The mean CES-D score was 6.5 (SD 6.4; median 5; range 0-44); 92% of the sample had a score below 16. After adjusting for covariates, statistically significant associations were observed between ever-use of any solvent, long duration of any solvent exposure, ever-use of gasoline, ever-use of petroleum distillates, and short duration of petroleum distillate exposure and continuous CES-D score (p < 0.05). Although nearly all associations were positive, fewer statistically significant associations were observed between metrics of solvent exposure and the dichotomized CES-D variable.

CONCLUSIONS

Solvent exposures were associated with depressive symptoms among farmers. Efforts to limit exposure to organic solvents may reduce the risk of depressive symptoms among farmers.

Depressive-like effect of prenatal exposure to DDT involves global DNA hypomethylation and impairment of GPER1/ESR1 protein levels but not ESR2 and AHR/ARNT signaling

Several lines of evidence suggest that exposures to Endocrine Disrupting Chemicals (EDCs) such as pesticides increase the risks of neuropsychiatric disorders. Despite extended residual persistence of dichlorodiphenyltrichloroethane (DDT) in the environment, the mechanisms of perinatal actions of DDT that could account for adult-onset of depression are largely unknown. This study demonstrated the isomer-specific induction of depressive-like behavior and impairment of Htr1a/serotonin signaling in one-month-old mice that were prenatally exposed to DDT. The effects were reversed by the antidepressant citalopram as evidenced in the forced swimming (FST) and tail suspension (TST) tests in the male and female mice. Prenatally administered DDT accumulated in mouse brain as determined with gas chromatography and tandem mass spectrometry, led to global DNA hypomethylation, and altered the levels of methylated DNA in specific genes. The induction of depressive-like behavior and impairment of Htr1a/serotonin signaling were accompanied by p,p'-DDT-specific decrease in the levels of estrogen receptors i.e. ESR1 and/or GPER1 depending on sex. In contrast, o,p'-DDT did not induce depressive-like effects and exhibited quite distinct pattern of biochemical alterations that was related to aryl hydrocarbon receptor (AHR), its nuclear translocator ARNT, and ESR2. Exposure to o,p'-DDT increased AHR expression in male and female brains, and reduced expression levels of ARNT and ESR2 in the female brains. The evolution of p,p'-DDT-induced depressive-like behavior was preceded by attenuation of Htr1a and Gper1/GPER1 expression as observed in the 7-day-old mouse pups. Because p,p'-DDT caused sex- and age-independent attenuation of GPER1, we suggest that impairment of GPER1 signaling plays a key role in the propagation of DDT-induced depressive-like symptoms.

Carbamate Insecticides Target Human Melatonin Receptors

Carbaryl (1-naphthyl methylcarbamate) and carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate) are among the most toxic insecticides, implicated in a variety of diseases including diabetes and cancer among others. Using an integrated pharmacoinformatics based screening approach, we have identified these insecticides to be structural mimics of the neurohormone melatonin and were able to bind to the putative melatonin binding sites in MT₁ and MT₂ melatonin receptors in silico. Carbaryl and carbofuran then were tested for competition with 2-[¹²⁵I]-iodomelatonin (300 pM) binding to hMT₁ or hMT₂ receptors stably expressed in CHO cells. Carbaryl and carbofuran showed higher affinity for competition with 2-[¹²⁵I]-iodomelatonin binding to the hMT₂ compared to the hMT₁ melatonin receptor (33 and 35-fold difference, respectively) as predicted by the molecular modeling. In the presence of GTP (100 μM), which decouples the G-protein linked receptors to modulate signaling, the apparent efficacy of carbaryl and carbofuran for 2-[¹²⁵I]-iodomelatonin binding for the hMT₁ melatonin receptor was not affected but significantly decreased for the hMT₂ melatonin receptor compatible with receptor antagonist/inverse agonist and agonist efficacy, respectively. Altogether, our data points to a potentially new mechanism through which carbamate insecticides carbaryl and carbofuran could impact human health by altering the homeostatic balance of key regulatory processes by directly binding to melatonin receptors.

Potential role of organochlorine pesticides in the pathogenesis of neurodevelopmental, neurodegenerative, and neurobehavioral disorders: A review

Organochlorine pesticides (OCPs) are persistent and bioaccumulative environmental contaminants with potential neurotoxic effects. The growing body of evidence has demonstrated that prenatal exposure to organochlorines (OCs) is associated with impairment of neuropsychological development. The hypothesis is consistent with recent studies emphasizing the correlation of environmental as well as genetic factors to the pathophysiology of neurodevelopmental and neurobehavioral defects. It has been suggested that maternal exposure to OCPs results in impaired motor and cognitive development in newborns and infants. Moreover, in utero exposure to these compounds contributes to the etiology of autism. Although impaired neurodevelopment occurs through prenatal exposure to OCs, breastfeeding causes postnatal toxicity in the infants. Parkinson's disease (PD) is another neurological disorder, which has been associated with exposure to OCs, leading to α-synuclein accumulation and depletion of dopaminergic neurons. The study aimed to review the potential association between pre- and post-natal exposure to OCs and impaired neurodevelopmental processes during pregnancy and neuropsychological diseases such as PD, behavioral alterations, seizures and autism.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Health risks faced by Turkish agricultural workers

Background. Individuals who make a living through agriculture and animal husbandry are faced with a variety of physical and psychological health risks. In many international studies, it has been shown that these risks can result in disease. The purpose of this study is to summarize the health risks faced by Turkish agricultural workers. Materials and Methods. This study used a nonrandom, convenience sample. The biopsychosocial health statuses of 177 farmers from 11 central villages in Kars, Turkey, were examined. Results. It was determined that the depression rate among the study group was 62.1%, the rate of physical health problems was 52.0%, and the rate of social isolation was 53.7%. There was a statistically significant difference between the depression scale scores and lower education levels, having ≥ three children, and physical health problems, as well as the physical condition of the farmers' homes. There was a significant difference between poor physical health and older age, lower education levels, having ≥ three children, and social isolation. Conclusions. In providing data-based evidence, it is believed that this study will contribute considerably to understanding the causality of health problems in this population and in planning the development of public health and veterinary services based on regional needs.

Fluoxetine treatment ameliorates depression induced by perinatal arsenic exposure via a neurogenic mechanism

Several epidemiological studies have reported an association between arsenic exposure and increased rates of psychiatric disorders, including depression, in exposed populations. We have previously demonstrated that developmental exposure to low amounts of arsenic induces depression in adulthood along with several morphological and molecular aberrations, particularly associated with the hippocampus and the hypothalamic-pituitary-adrenal (HPA) axis. The extent and potential reversibility of this toxin-induced damage has not been characterized to date. In this study, we assessed the effects of fluoxetine, a selective serotonin reuptake inhibitor antidepressant, on adult animals exposed to arsenic during development. Perinatal arsenic exposure (PAE) induced depressive-like symptoms in a mild learned helplessness task and in the forced swim task after acute exposure to a predator odor (2,4,5-trimethylthiazoline, TMT). Chronic fluoxetine treatment prevented these behaviors in both tasks in arsenic-exposed animals and ameliorated arsenic-induced blunted stress responses, as measured by corticosterone (CORT) levels before and after TMT exposure. Morphologically, chronic fluoxetine treatment reversed deficits in adult hippocampal neurogenesis (AHN) after PAE, specifically differentiation and survival of neural progenitor cells. Protein expression of BDNF, CREB, the glucocorticoid receptor (GR), and HDAC2 was significantly increased in the dentate gyrus of arsenic animals after fluoxetine treatment. This study demonstrates that damage induced by perinatal arsenic exposure is reversible with chronic fluoxetine treatment resulting in restored resiliency to depression via a neurogenic mechanism.