Symptoms of Neurotoxicity among Carpenters Living in Rural Ecuador: A Population-based Study (The Atahualpa Project)

BACKGROUND: There is no information on the prevalence of symptoms related to neurotoxicity among carpenters working in underserved populations. To assess the magnitude of the problem, we conducted a population-based study in Atahualpa, a rural Ecuadorian village, where most men work as carpenters under poor safety conditions. METHODS: All men aged 40–75 years living in Atahualpa were identified during a door-to-door survey and evaluated with a general demographic questionnaire, the Q16 questionnaire, the depression axis of the Depression Anxiety Stress Scale-21, and the Montreal Cognitive Assessment (MoCA). RESULTS: Among 230 participants, 63% were carpenters. Seventy participants (30%) had a positive Q16 questionnaire (≥6 points), which suggested neurotoxicity. In a logistic regression model adjusted for age, education, alcohol intake, symptoms of depression, and MoCA score, the proportion of Q16 positive persons was 39.1% for carpenters and 15.9% for noncarpenters (odds ratio: 3.53, 95% confidence interval: 1.75–7.15, P < 0.0001). In a generalized linear model, adjusted mean scores in the Q16 questionnaire were 4.9 for carpenters and 3.6 for noncarpenters (β: 1.285, standard error: 0.347, P < 0.0001). There was no correlation between scores in the Q16 questionnaire and the MoCA (Pearson correlation coefficient = −0.02), and the only significant covariate in the multivariate linear model was age, with every 10 years of age difference contributing 0.64 points in the Q16 questionnaire. CONCLUSION: This study shows a high prevalence of symptoms associated with neurotoxicity among carpenters after adjusting for a number of confounders. Long-term exposure to toxic solvents is the most likely explanation to this finding.