Cholinesterase Status of Some Ethiopian Pest Control Workers Exposed to Organophosphate Pesticides

No Thumbnail Available



Journal Title

Journal ISSN

Volume Title


Addis Ababa University


A study was conducted in 430 pest control workers with that of 161 comparable controls. The health risks and associated morbidity from occupational exposure to organophosphate (OP) pesticides was determined and factors ttat may contribute to a greater pesticide exposure were identified. Plasma and RBC cholinesterase (GhE) activities were determined using electrometric methods. Symptoms of OP poisoning and risk factors for exposure associated with pesticide use were assessed through a questionnaire, developed based on the WHO (1982) and WHO-UNDP (Maroni et al 1986) recommendations. To evaluate the possible liver dysfunction, plasma levels of alkaline phosphatase (AP) and gl utamic pyruvic transaminase (i;PT) ',.;ere determined using diagnostic ki~s number 6391 anrj 14442520 respectively. Significantly lower plasma and RBC GhE activities were found in the exposed workers compared to the controls (P<0.001); 58 (~3,5~\ and 47 (10.9%) of the exposed workers ~ad plasma and Rae '::l:!; a,::::.~vities below the lowe!' ::"Lni: of t:-n? controls respectively. Compared to the workers in the other job categories, the "spray men" and those wi:h duratio~, of exposure below 5 years were identified to be tta most affected groups. Normal AP and GPT levels without significant differencee from the co~trols were noted, suggesting the atsence of any marked liver im~airemnet at this level of exposu~e. Symptoms of OP were frequent in the exposed workers than in the controls. However, except for sweating and weakness (p<0.05), other symptoms reported were not significantly associated with low RBC and plasma ChE activities. Surveys of the risk factors for possible pesticide poisoning revealed that lack of knowledge and poor personal hygiene were prominent among the exposed population _n general, the present study showed that :here are ap~~~e~~ health risks associated with OP exposure. Measures that s~oul~ be considered to minimize the health effects from the use of OP pesticides are cecommended; such as pre-placenmer:t and periodic medical examinations, the use of appropriate protective jevices and creation of awareness among the w:rkers of the risks of pesticide poisoning.