Heath concern for Kenyan farm workers

Grace Ohaya-Mitoko has assessed the health hazards posed by pesticide handling, storage and use on agricultural estates and small farms in selected communities in Kenya.

Acetylcholinesterase inhibition (an indicator of occupational exposure to organophosphate and/or carbamate insecticides) was investigated in 666 Kenyan agricultural workers. Out of these, 58.6% were mainly pesticide applicators and (276) 41.4% unexposed controls from the four rural agricultural areas during 1993 and 1994. Acetylcholinesterase inhibition was found in all exposed individuals and led to an average in baseline acetylcholinesterase levels of 33%. The unexposed group had a non-significant decrease of only 4%. The exposed subjects in Naivasha area (flower growers) had the largest inhibition (36%) followed by those in Homabay (cotton growers) (35%) and Wundayi (vegetable growers) (33%). Those in Migori (tobacco growers) had, by far, the least inhibition of acetylcholinesterase activity (26%). Acetylcholinesterase activity levels of 115 exposed individuals (29.6%) and no controls were depressed to values below 60% of baseline levels.  
    The dramatic acetylcholinesterase inhibition observed can lead to chronic clinical and sub-clinical intoxication. There is, therefore, an urgent need for primary prevention programmes to monitor and to address occupational exposures to these hazardous substances in agriculture in Kenya and other developing countries. General recommendations, include identifying the specific health-related behavioural and environmental factors that could be linked to the health problems.

Grace Ohaya-Mitoko, Occupational Pesticide Exposure Among Kenyan Agricultural Workers, Kenyan Medical Research Institute, and Department of Epidemiology and Public Health, Wageningen Agricultural University, PB 238, 6700 EV, The Netherlands.

[This article first appeared in Pesticides News No. 38, December 1997, page 17]