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

Abstract

Purpose Although organic solvents are often used in agricultural operations, neurotoxic effects of solvent exposure have not been extensively studied among famers. 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.

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

“…Among the developed country literature, United States studies have also studied links between pesticide exposure and farmer mental health. Some pesticides are neurotoxic, which are said to directly affect neural systems known to cause mental illness [108,109,110,111,112,113] and depression [56,60,64,65,70,72,74,114,115,116,117,118,119,120,121,122,123]. Some studies have examined pesticide exposure in general, while others considered specific compounds such as organophosphates.…”

Psychological and Physical Health of Organic and Conventional Farmers: A Review

“…Feelings about the future affected work satisfaction: being depressed decreased it but being optimistic or feeling good increased satisfaction [32]. In addition, exposure to any solvent, gasoline, or petroleum distillates increased depression scores on the CES-D, but exposure to paint thinner did not have an effect [53]. Five correlates to conventional farmers' health were identified, two linked with emotions and three linked to pesticides.…”

“…Similar to organic farmers, Rickson et al (1999) measured predictors of farmers' work satisfaction [32]. Siegel et al (2017) presented data about the effects of pesticide exposure on depression, measured by the CES-D [53].…”

Drug use disorder following early life exposure to tetrachloroethylene (PCE)-contaminated drinking water: a retrospective cohort study

“…Because of its small size and lipid solubility, PCE easily crosses the blood brain barrier and selectively concentrates in the brain and other lipophilic tissue. Epidemiologic studies of adults with occupational exposure to PCE and related solvents have reported increases in anxiety and depression [8,9,11,[16][17][18] and impairments in cognition, memory, attention, executive function and trigeminal nerve and vestibular function [8][9][10][11][12][13][14][15].…”

“…Studies of adults exposed to PCE and related solvents in occupational settings have reported decrements in cognition, memory, attention, executive function, and trigeminal nerve and vestibular function [8][9][10][11][12][13][14][15]. Studies have also linked occupational exposure to increases in anxiety and depression [8,9,11,[16][17][18].…”