McConnell_1999_Environ.Res_81_87

The effect of exposure to pesticides among children in a Nicaraguan community in the path of rain water runoff from a large crop-dusting airport was evaluated by measuring plasma cholinesterase. Mean cholinesterase activity in 17 children in the path of runoff was 2.4 international units/ml blood/min, lower than the 2.9 IU/ml/min measured in a group of 43 children from an unexposed community (difference=0.49 IU/ml/min; 95% C.I. 0.24, 0.76). Six (35%) of the 17 exposed children had abnormally low cholinesterase levels. A possible explanation for this physiological effect of exposure to pesticides is the dermal absorption which may have occurred among children playing barefoot in puddles grossly contaminated by runoff from the airport. Drinking water from a well in the exposed community demonstrated low level residues of cholinesterase-inhibiting pesticides, although contamination with toxaphene (not a cholinesterase inhibitor) exceeded by over 8-fold the United States Environmental Protection Agency maximum permissible concentration in drinking water. The difficulty in measuring health effects resulting from environmental pesticide contamination, and in controlling exposure resulting from the rapidly increasing use of pesticides, is a growing problem for developing countries like Nicaragua.