Measured versus simulated dietary pesticide intakes in children

Children's dietary pesticide intakes can be measured directly through duplicate diet samples, but instead are frequently estimated using national residue data. We compared organophosphorus and pyrethroid pesticide intakes from conventional fruit, fruit juices and vegetables measured for two cohorts of children aged 3-11 years in the Children's Pesticide Exposure Study (CPES) with corresponding intakes simulated using CPES consumption and body weight data and residue data from the US Pesticide Data Program (PDP). We calculated daily measured pesticide intakes by multiplying grams eaten with measured concentrations and dividing by body weight. For the simulated intakes we combined the CPES consumption and PDP residue data, randomly sampling the PDP data 500 times in order to create distributions of daily intakes for each cohort, including 95% uncertainty intervals for each percentile. In all cases, the measured medians fell below the lower uncertainty bounds of the simulated medians, reflecting the lower detection limits of CPES versus PDP and the high number of non-detects in each. Upper percentile measured intakes were generally lower as well, except for higher measured intakes of phosalone from watermelon. This work shows that using PDP data could generate probabilistic estimates of dietary pesticide intakes that do not differ appreciably from measured intakes except in some cases.