Organophosphate exposure in pesticide formulation and packaging factories in Harare, Zimbabwe

A cross sectional study was conducted in September 1989 in order to estimate the prevalence of organophosphate exposure and to identify factors associated with increased organophosphate exposure in pesticide producing factories in Harare, Zimbabwe. Sixty five workers entered the study with 45 of them providing blood specimens. The mean cholinesterase level was 75.3 pc (standard deviation 21.07 pc). Twenty (44.4 pc) workers had cholinesterase levels of less than 75 pc. The workers had adequate knowledge (75 pc+) of the importance of protective devices but had less knowledge of about 50 pc of health effects of pesticides. Smoking (t = 3.49; degrees of freedom (df) = 43; p < 0.01) and eating (t = 2.14; df = 43; p < 0.05) at work place were associated with increased exposure to organophosphate. The number of symptoms was not correlated with cholinesterase levels (Spearman's rank correlation coefficient--0.70; p = 0.12). We conclude that a significant number of workers were exposed to organophosphate. Increased personal hygiene such as washing hands before eating or smoking should reduce the amount of exposure.