Integrated Pest Management and children's exposures to pyrethroids in low-income public housing dwellings in Boston, MA

摘要

Background: Pyrethroid pesticides are used extensively in agriculture and in home and building applications. Children are recognized as most at risk to dietary and residential exposures due to their still developing organs and underdeveloped detoxification processes. Integrated pest management (IPM) in housing is gaining popularity as a more comprehensive and less pesticide-driven method for reducing pests, however IPM programs instituted by large housing complexes have not been evaluated for efficacy. Aims: We sought to evaluate whether a newly introduced IPM program in low-income housing could alter children's pyrethroid exposures. Methods: We tracked 20 children in a Boston public housing complex over 18 months, collecting urine samples over 3-day periods for each of 6 consecutive months before and after IPM implementation with six months between (up to 72 samples per child). Samples were analyzed for 6 pyrethroid metabolites. Results: Prior to IPM implementation, one or more pyrethroid metabolites were present in every urine sample, with cis- and trans-2,2-(dichloro)-2-dimethylvinylcyclopropane carboxylic acid (DCCA), 3-phenoxybenzoic acid (3PBA), and cis-2,2-(dibromo)-2-dimethylvinyl-cyclopropane carboxylic acid (DBCA) detected in over 89% of samples. Remaining metabolites were detected in under half of collected samples. While 3PBA and DCCA medians (0.5 ng/ml) were similar to National Health and Nutrition Evaluation Survey values, 95%ile values rose to 7 ng/ml and peak exposure events (up to 235 ng/ml (DCCA) and 372 ng/ml (3PBA)) were 5-11 times higher than other studies. FPBA and DBCA stayed below 1 ng/ml up to the 95%ile. Post-IPM urine levels will be reported and compared to pre-IPM samples. Observations of IPM performance included a decline in pesticide use by families. While visits by pest professionals increased, use of pyrethroid sprays remained low and widespread application of baits and gels were reported. Conclusions: Pesticide exposures are common in low income housing and use of IPM may serve to reduce children's exposures.