Assessment of oxidative stress and its association with biological markers and occupational factors in Tunisian farmworkers chronically exposed to pesticide mixtures.

The aim was the assessment of oxidative stress (OS) and its relationships with biomarkers and occupational factors in farmworkers exposed to pesticides(Ps). Analyses of biological and OS biomarkers were performed for both exposed and unexposed individuals. Multivariate analyses were applied to study associations between these biomarkers. Associations between OS biomarkers and biological parameters were revealed only in farmworkers. The spraying mode and duration predicted low GSH levels. The Ps cocktail used correlated with increased MDA(r=0.332;p=0.037), decreased GPx(r=-0.363;p=0.021), and inversely with acetylcholinesterase (r=-0.460;p=0.003), and it was correlated with anxiety. The latter was also associated with the Ps exposure index. However, butyrylcholinesterase(BChE) decreased specifically in workers suffering from asthenia (r=-0.338;p=0.033). Long-term exposure to Ps mixtures may induce OS and reduce antioxidant capacity, leading to neurological or neuropsychic impairement. Hence, OS biomarkers are useful as early-effect biomarkers of pesticide exposure.