An observational study on the potential exposures of 111 preschool children to phthalates in their everyday environments

This study was designed to examine the exposures of preschool children to chemicals commonly found in their everyday surroundings. A primary objective was to identify potential sources and routes of the children's exposures to two phthalates used in household and personal care products (di-n-butyl phthalate [DBP]) and in building materials (benzylbutyl phthalate [BzBP]). Participants were randomly selected from homes and daycare centers in 12 North Carolina and Ohio counties from 2000-2001. Monitoring was performed over a 48-hr period. Samples collected included urine, food, air, dust, soil, and hand wipes. In 2006, a subset of the children's archived urine samples was analyzed for mono-n-butyl phthalate (MBP) and monobenzyl phthalate (MBzP), the main metabolites of DBP and BzBP, respectively. We report the preliminary results for the levels of DBP and BzBP in multimedia samples collected at 41 homes and 24 daycare centers and the urinary concentrations of their metabolites in 111 children. The phthalate diesters were detected most often in indoor air (94%) for DBP and dust (84%) for BzBP at both locations. Median levels for DBP were 305.7 ng/m³ (indoor air) and 43.7 ng/g (solid food). Median levels for BzBP were 18, 314.1 ng/g (dust) and 36.4 ng/g (solid food). The median urinary concentrations were 41.4 ng/mL (MBP) and 53.1 ng/mL (MBzP). These results showed that these children were potentially exposed to both phthalates from several sources and routes. The biomarkers of exposure confirm that these children were exposed to and did absorb phthalates into their bodies.