A Longitudinal Approach to Assessing Urban and Suburban Children’s Exposure to Pyrethroid Pesticides

Department of Environmental and Occupational Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA.
Environmental Health Perspectives (Impact Factor: 7.98). 10/2006; 114(9):1419-23. DOI: 10.1289/ehp.9043
Source: PubMed


We conducted a longitudinal study to assess the exposure of 23 elementary school-age children to pyrethroid pesticides, using urinary pyrethroid metabolites as exposure biomarkers. We substituted most of the children's conventional diets with organic food items for 5 consecutive days and collected two daily spot urine samples, first morning and before bedtime voids, throughout the 15-day study period. We analyzed urine samples for five common pyrethroid metabolites. We found an association between the parents' self-reported pyrethroid use in the residential environment and elevated pyrethroid metabolite levels found in their children's urine. Children were also exposed to pyrethroids through their conventional diets, although the magnitude was smaller than for the residential exposure. Children's ages appear to be significantly associated with pyrethroids exposure, which is likely attributed to the use of pyrethroids around the premises or in the facilities where older children engaged in the outdoor activities. We conclude that residential pesticide use represents the most important risk factor for children's exposure to pyrethroid insecticides. Because of the wide use of pyrethroids in the United States, the findings of this study are important for both children's pesticide exposure assessment and environmental public health.

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Available from: Dana B Barr, Jan 10, 2014
    • "Therefore, the Diversity and Autocorrelation (D & A) method (Glen et al., 2008) was used to construct longitudinal food consumption diaries. Total caloric consumption was used as the key variable, with D and A statistics set to 0.3 and 0.1, respectively based on longitudinal data from Lu, C. et al. (Lu et al., 2006). Dietary exposures of MeHg from fish were simulated for a one year period, and exposure durations of 1 day, one week, two weeks, one month, three months, six months, and twelve months were calculated for comparison. "
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    • "nervous system. The site of action of pyrethroids is the voltagedependent sodium channels, but the chloride, calcium, and other channels may also be targets (Soderlund et al. 2002; Ray and Fry, 2006). The Type II pyrethroids were designed to be more photostable and are more frequently used to control for various types of insect pests on agricultural crops, in and around residential dwellings, and on pets. "
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