A method to screen U.S. environmental biomonitoring data for race/ethnicity and income-related disparity.

BACKGROUND: Environmental biomonitoring data provide one way to examine race/ethnicity and income-related exposure disparity and identify potential environmental justice concerns. METHODS: We screened U.S. National Health and Nutrition Examination Survey (NHANES) 2001-2008 biomonitoring data for 228 chemicals for race/ethnicity and income-related disparity. We defined six subgroups by race/ethnicity-Mexican American, non-Hispanic black, non-Hispanic white-and income-Low Income: poverty income ratio (PIR) <2, High Income: PIR ≥ 2. We assessed disparity by comparing the central tendency (geometric mean [GM]) of the biomonitoring concentrations of each subgroup to that of the reference subgroup (non-Hispanic white/High Income), adjusting for multiple comparisons using the Holm-Bonferroni procedure. RESULTS: There were sufficient data to estimate at least one geometric mean ratio (GMR) for 108 chemicals; 37 had at least one GMR statistically different from one. There was evidence of potential environmental justice concern (GMR significantly >1) for 12 chemicals: cotinine; antimony; lead; thallium; 2,4- and 2,5-dichlorophenol; p,p'-dichlorodiphenyldichloroethylene; methyl and propyl paraben; and mono-ethyl, mono-isobutyl, and mono-n-butyl phthalate. There was also evidence of GMR significantly <1 for 25 chemicals (of which 17 were polychlorinated biphenyls). CONCLUSIONS: Although many of our results were consistent with the U.S. literature, findings relevant to environmental justice were novel for dichlorophenols and some metals.

Pilot study of pesticide knowledge, attitudes, and practices among pregnant women in northern Thailand.

An estimated 200,000 children born in Thailand each year are at risk of prenatal exposure to pesticides and associated neurodevelopmental outcomes because of their mothers' agricultural occupations. Children born to non-agricultural workers may also be at risk of exposure from other pathways of maternal pesticide exposure, including exposure through home use, diet, and other environmental media. Pesticide exposure in Thailand has been linked to unsafe practices and beliefs about pesticides. However, limited information exists on pesticide knowledge, attitudes, and practices among pregnant women in Thailand or elsewhere. Obtaining this information is essential to understand the factors associated with prenatal pesticide exposure, identify populations potentially at risk, and ultimately protect pregnant women and their children. We administered surveys to 76 pregnant women in northern Thailand and used multivariable logistic regression to evaluate associations among pesticide-related knowledge, pregnancy trimester, and pesticide use behavior. In this pilot study, lower knowledge score and earliest trimester of pregnancy were marginally (p < 0.1) associated with unsafe practices in the home, but not at work. Women who worked in agriculture or applied pesticides before becoming pregnant, or who had a previous child were significantly (p < 0.05) more likely to engage in unsafe behaviors in the home during their current pregnancy. We preliminarily conclude that increasing pesticide-related knowledge among pregnant women may help promote safe practices and reduce prenatal exposure. Knowledge-based interventions may be most effective when implemented early in pregnancy and targeted to agricultural workers and other sub-populations at risk of pesticide exposure.

Dietary patterns among the Metro Atlanta Cohort: implications for population-based longitudinal dietary pesticide exposure and risk assessment.

Characterizing dietary consumption patterns is critical to dietary pesticide exposure assessment. We compared consumption patterns between adults (age 18-60) in the Metro Atlanta Cohort (MAC), a longitudinal study of pesticide exposure among Atlanta residents, and US National Health and Nutrition Examination Survey (NHANES) adults. We focused on foods commonly eaten by US adults and foods likely to contain certain pesticide residues. MAC participants provided consumption data for 6 days per month for 1 year using a web-based data collection tool. We defined "percent eaters" as the percent of participants who reported eating a particular food in 24 h. We computed the NHANES weighted percent eaters and 95% confidence limits (CLs) using the 24-h dietary recall data. We calculated the MAC percent eaters for each sampling day and the percent of days this number fell below, within, or above the NHANES 95% CLs. We also re-sampled the MAC percent eaters across sampling days to find whether the resulting distribution resembled the NHANES estimate, and used the Kruskal-Wallis test to evaluate whether season affected the number of MAC eaters of a particular food on a given sampling day. In general, across all sampling days, a greater proportion of MAC participants reported eating banana, broccoli, cream, grapes, lettuce, onion, peach, pear, peas, strawberries, string beans, and tomatoes than the national estimate, whereas the proportion of apple, spinach, ketchup and white bread/roll eaters was similar, and the proportion of milk drinkers was lower. Season predicted the number of MAC peach and strawberry eaters but not other foods. The data show how a higher proportion of Atlanta adults may eat certain foods (e.g., peaches in summer or strawberries in spring) than the national average depending on season or other factors. An exposure assessment that ignored this difference could underestimate dietary pesticide intakes.

Comparison of food consumption frequencies among NHANES and CPES children: implications for dietary pesticide exposure and risk assessment.

Characterizing food consumption patterns among children is critical to dietary pesticide exposure assessment. We have used public release data from the US National Health and Nutrition Examination Survey (NHANES) and the longitudinal Children's Pesticide Exposure Study (CPES) to illustrate the magnitude of potential error introduced by using national-scale, cross-sectional data to estimate the consumption frequencies for smaller cohorts. We focused on foods commonly consumed by children in the target CPES age and income group (3-11 years; annual household income >$75,000) and foods likely to contain organophosphorus or pyrethroid pesticide residues. We defined "percent eaters" as the percentage of study participants who reported eating a particular food in a 24-h period. We computed the weighted percent eaters and 95% confidence limits (CL) for the target age/income group using the NHANES 24-h dietary recall data and compared these with the CPES percent eaters by sampling day and season. For certain foods, particularly the seasonally available produce (for example, apples, peaches/nectarines, melon, grapes, pears, strawberries), soy milk, and peanut butter, the CPES percent eaters fell outside the NHANES 95% CLs on many sampling days. For other foods (for example, orange juice and cow's milk), differences were not readily apparent. Although the differences we observed for certain foods may be, in part, because of measurement error, they also likely reflect seasonal and geographic patterns among the CPES data that the public release NHANES data do not capture. Using NHANES data to estimate pesticide intakes from strawberries, for example, may underestimate the exposure of the CPES children, as significantly more CPES than NHANES children ate strawberries on many sampling days. For other sampling days or other foods, overestimation is also possible.