Toxicologie environnementale et analytique

The Occurrence of Pesticides and Polycyclic Aromatic Hydrocarbons in Residential Dust in North Carolina

Abstract

Rebecca Anthopolos, Martha Keating, David Camann, and Marie Lynn Miranda

The objective of this study was to characterize the occurrence and concentration of pesticides and polycyclic aromatic hydrocarbons (PAH) in household dust in North Carolina. Human exposure to these contaminants in the indoor environment is of concern since little degradation takes place indoors resulting in chronic exposure to a mixture of contaminants. In addition, children may be more highly exposed due to hand-to-mouth activities and increasing time spent indoors. We recruited 199 households in Central and Eastern North Carolina and collected composite dust samples over two April-October sampling seasons during 2003 and 2004. Dust samples were analyzed for 16 pesticides (α-chlordane, γ-chlordane, 2,4-D(2-ethylhexyl) ester, alachlor, carbaryl, chlorpyrifos, cis- and transpermethrin, 4,4’-DDE, 4,4’-DDT, dieldrin, diazinon, heptachlor, lindane, methoxychlor, and ortho-phenylphenol) andfour PAH compounds (benzo(b)fluoranthene , chrysene/iso-chrysene, benzo(a)pyrene, and benz(a)anthracene). The frequency of detection varied for the pesticides; the median number of pesticides detected in sampled homes was seven. The four PAH were found in more than 97% of sampled homes. Detection frequency and concentration of insecticides banned for residential uses were significantly associated with whether the residence was built before or after the ban year (P<0.001 in all cases except for dieldrin where P<0.01, and methoxychlor). Under maximum exposure scenarios, somewhat elevated health risk estimates were calculated, with the majority of the risk attributable to exposure to the banned insecticides dieldrin and DDT. This study provides additional regional data about the mixture and level of contaminants in household dust in the southeastern U.S.