Sleep disturbances and neurotoxicity in workers exposed to hydrocarbons. An observational study from Algeria.

ABSTRACT

BACKGROUND: Occupational exposure to solvents may lead to neurotoxicity and sleep disturbances. We aimed to investigate the association of occupational exposure to petroleum-derived hydrocarbons with neurotoxicity and sleep disturbance symptoms. METHODS: We included male workers handling/distributing petroleum products (exposed, n = 250) and electricians (non-exposed, n = 250) from two companies in Tlemcen (Algeria). Neurotoxicity was evaluated with the Q-16 questionnaire, and sleep disturbances with the Epworth and the Berlin questionnaires. Multivariable Poisson regression models with robust error variances were applied obtaining risk ratios (RR) and their 95% confidence interval (CI). RESULTS: Overall, the prevalence of reported neurotoxicity and sleep disturbance symptoms was higher in exposed than in non-exposed workers. Significant adjusted associations were observed for neurotoxicity, snoring, and excessive sleepiness (RR = 2.2, CI 1.7-2.8; RR = 1.4; CI 1.1-1.7; RR = 1.3, CI 1.2-1.5, respectively). No significant associations were observed with the Epworth score. CONCLUSIONS: Our questionnaire-based cross-sectional study suggests that exposure to petroleum-derived hydrocarbons is associated with self-reported sleep disturbances and neurotoxicity symptoms.