Organophosphorus and pyrethroid insecticide urinary metabolite concentrations in young children living in a southeastern United States city

Division of Environmental Hazards and Health Effects, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA, USA.
Science of The Total Environment (Impact Factor: 4.1). 11/2009; 408(5):1145-53. DOI: 10.1016/j.scitotenv.2009.10.022
Source: PubMed


Pesticide metabolites are routinely measured in the urine of children in the United States. Although the sources of these metabolites are believed to include residues in food from agricultural applications and residues from applications in everyday environments (e.g., homes), few studies have been able to demonstrate an association between indoor residential pesticide applications and pesticide metabolite concentrations. To better quantify the effects of potential risk factors related to demographics, household characteristics, occupation, and pesticide use practices on urinary biomarker levels, we performed a study in a city (Jacksonville, Florida) previously determined to have elevated rates of pesticide use. We enrolled a convenience sample of 203 children ranging in age from 4 to 6 years; their caregivers completed a questionnaire and the children provided a urine sample, which was analyzed for a series of organophosphorus and pyrethroid insecticide metabolites. The questionnaire responses substantiated much higher pesticide use for the study participants as compared to other studies. Urinary metabolite concentrations were approximately an order of magnitude higher than concentrations reported for young children in other studies. Few statistically significant differences (at the p<0.05 level) were observed, however, several trends are worth noting. In general, mean urinary pesticide metabolite concentrations were higher for males, Caucasians, and those children living in homes with an indoor pesticide application occurring within the past four weeks. Comparing the urinary pesticide metabolite concentrations in this study to those reported in the NHANES and GerES studies showed that the children living in Jacksonville had substantially higher pyrethroid pesticide exposures than the general populations of the United States and Germany. Further research is needed in communities where routine pesticide use has been documented to obtain information on the most important routes and pathways of exposure and to develop the most effective strategies for reducing pesticide exposures for children.

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    • "In environmental exposure and health research, CRc is used to " normalize " urinary levels of other analytes; this adjustment is performed most frequently on urinary metabolites of exogenous chemicals. Here, concentrations of chemical biomarkers (reflecting either exposures [Koch et al., 2005; Baker et al., 2005; Naeher et al., 2010] or biological responses [Bales et al., 1984; Price et al., 2005; Emond et al., 2013]) vary with changing urine output. Dividing chemical biomarker concentration by CRc (yielding a creatinine-adjusted concentration) might remove some variation produced by increased or decreased urine output (Barber and Wallis, 1986; Boeniger et al., 1993). "
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    • "Exposure to pesticides is more prevalent in individuals working in agricultural sectors such as farmers, peasants, farm workers. They are at increased risk of direct exposure while others may be exposed due to food contamination [63]. Contaminants get accumulated in the body and change the gene expression profile in exposed tissues. "
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    • "The presence of pyrethroid metabolites, such as 3-phenoxybenzoic acid, in the urine of U.S. and German residents indicates that the population is widely exposed to this family of pesticides; furthermore, children have higher exposures than adolescents and adults [2-5]. "
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