Determining Child Phthalate Exposure

(Photo Credit: Mark Evans/Getty Images)

Vinyl flooring in the home could be a key source of phthalates ingested and inhaled by children, according to a new study published in the Journal of Exposure Science and Environmental Epidemiology.¹ The work was performed as part of an ongoing project by the Columbia Center for Children’s Environmental Health (CCCEH) at Columbia University in New York, USA, and followed a cohort of women and children living in New York city to investigate the impact of phthalate exposure on the health of children.

Exposure to butylbenzyl phthalate (BBzP) and di(2-ethyhexyl) phthalate (DEHP) - commonly used vinyl plasticizers - had been previously associated with the occurrence of asthma and airway inflammation in children in an earlier study.2 Lead author Allan C. Just told The Column: “As part of our previous work to understand these exposures, we found that the women in our study had fairly reproducible levels of the urinary metabolite of BBzP in repeated samples collected over late pregnancy and this surprising result led us to wonder if there was a consistent exposure source given that these non‑persistent chemicals are rapidly excreted (within a few hours).”

More than 700 women were enrolled into the CCCEH birth cohort between 1998 and 2006 at prenatal clinics in New York, and a subset of around 243 children who were five years or older were selected for this study. Indoor air samples - including particles that can be respired - were collected from the living spaces of the child and subsequently analyzed using gas chromatography coupled with mass spectrometry (GC–MS). Spot urine samples were collected from children and were analyzed using high performance liquid chromatography tandem mass spectrometry (HPLC–MS–MS).

The authors found that urine samples from children living in homes with vinyl or linoleum flooring contained significantly higher concentrations of BBzP as did indoor air samples; however, they were surprised to not see any association between flooring type and urinary metabolite levels of DEHP. Just explained: “While our results point to common building materials in the home as potential sources of one phthalate (BBzP), they don’t explain the exposure patterns for the more widely used DEHP - although we still found DEHP in every air sample and its metabolites in every urine. While exposure to all of the phthalates vary widely, it is thought that dietary contamination may be a main driver of exposure
to DEHP.” - B.D.

References

1. A.C. Just et al. Journal of Exposure Science and Environmental Epidemiology DOI:10.1038/jes.2015.4 (2015).

2. R.M. Whyatt, Environmental Health Perspectives 122(10), 1141–1146 (2014).

This article is from The Column. The full issue can be found here>>