Determination of oxidative stress markers and serum cholinesterase among pesticide sprayers in southern Brazil

Abstract

Small farmers generally spray pesticides manually and often do not use complete protective equipment. The standard test to detect pesticide exposure, which may be associated with toxicity, is the determination of serum cholinesterase, but in chronic exposure to low doses, this test is less sensitive. In this study, in a group sampled among pesticide sprayers without signs of intoxication, cholinesterase, thiobarbituric acid reactive substances (TBARS), catalase (Cat), and superoxide dismutase (Sod) activities were analyzed. Cholinesterase activity was only slightly lower in the farmer group in relation to the control group. However, TBARS and Cat activities were 3-fold increased in the farmers in comparison to the controls. Sod activity was similar in both groups. The group of pesticide sprayers that did not use the complete protective equipment presented a significantly higher level of TBARS than the group that used the complete protective equipment. Therefore, the determination of TBARS and catalase can be useful to identify individuals that are chronically exposed to low doses of pesticides.

Keywords:

• oxidative stress
• cholinesterase
• pesticides
• human monitoring