Early pesticide exposure and later mortality in rural Africa: a new hypothesis.
Season of birth correlates with approximately 10-fold increased risk of early mortality from infectious disease in parts of The Gambia, West Africa. The increased early death occurred in individuals aged 25-50, who were born during the nonharvest season when stored groundnuts constituted a significant portion of the diet. Insect pests destroy stored groundnuts if not prevented, thus, the people mix insecticides into the storage bags before sealing of the bags. This procedure has been used since the 1970s or earlier, with the specific insecticide agents varying by availability. Organochlorine insecticides including DDT, lindane, and chlordane were added to bags until as recently as the 1980s. Subsequently organophosphates and pyrethroids became available and largely replaced the organochlorine agents. These agents both cross the placenta and are secreted into milk. Further, all are recognized immunotoxicants. These collective observations suggest the possibility that perinatal immunotoxic pesticide exposure, in individuals born during nonharvest months, may impair development of the immune system and increase risk of early death from infectious disease. Additional studies are planned to investigate our hypothesis that pesticide-related developmental immuntoxicity may contribute, in part, to Gambian seasonal mortality.
Ofordile
O N
ON
Medical Research Council (MRC), Keneba, MRC Laboratories, The Gambia, West Africa.
Prentice
A M
AM
Moore
S E
SE
Holladay
S D
SD