Parichart Visuthismajarn

Biological Monitoring of Organophosphate Pesticides in Preschool Children in an Agricultural Community in Thailand

Abstract Organophosphate pesticide exposures of preschool children in a Thailand agricultural community and reference children living outside the farm area in the same subdistrict were determined. Levels of dialkylphosphate (DAP) metabolites were measured in first-morning-void urine samples. During the dry season (April-May), the farm children excreted significantly igher levels of all DAP metabolites than the reference children did (Mann-Whitney U test, p < 0.05; Wilcoxon signed-rank text, p < 0.05). During the wet season (September-October), DAP metabolite levels were similar in the two groups. Reference children showed no significant difference related to season. Pesticide spraying during the dry season is a likely cause of the farm childrens organophosphate exposures.

Analytical Method Developed for Measurement of Dialkylphosphate Metabolites in Urine Collected from Children Non-Occupationally Exposed to Organophosphate Pesticides in an Agricultural Community in Thailand

There has been increasing concern in regards to organophosphate (OP) pesticide exposure among farm workers and their families in Thailand’s agricultural areas. Therefore, the development of an analytical method for estimating OP pesticide exposure is necessary to allow for monitoring of OP pesticide exposures within these populations. This paper describes an analytical method developed to measure dialkylphosphate (DAP) metabolites in urine. The methods in this study are important in the biological monitoring of OP metabolites in agricultural families in Thailand and can be used as an initial guidance procedure in any environmental toxicological laboratory in Thailand.

Organophosphate Pesticide Exposures of Traditional and Integrated Pest Management Farmers from Working Air Conditions: A Case Study in Thailand

Abstract Concentrations of organophosphate pesticides, including chlorpyrifos and methyl parathion, were measured in ambient air breathed by farmers in Tambon Bang Rieng, Thailand. An exposure assessment and comparison was made between the levels of pesticide exposure of traditional and integrated pest management (IPM) farmers. Thirty-three air samples were collected during pesticide spraying. Traditional farmers were exposed to higher levels of the pesticide(s), with an average concentration of 0.19 mg/m3, compared with 0.037 mg/ m3 for the IPM farmers. It was estimated that a farmer of Tambon, Bang Rieng would be exposed to 81–12,261 mg of the organophosphate pesticide(s) via inhalation throughout his or her lifetime. Moreover, traditional farmers absorbed more of pesticide via inhalation than did IPM farmers.