TitleDifferential exposure to organophosphate flame retardants in mother-child pairs.
Publication TypeJournal Article
Year of Publication2019
AuthorsGibson EA, Stapleton HM, Calero L, Holmes D, Burke K, Martinez R, Cortes B, Nematollahi A, Evans D, Anderson KA, Herbstman J
Date Published2019 Mar
Adult, Child, Child Development, Child, Preschool, Cohort Studies, Dust, Environmental Exposure, Female, Flame Retardants, Humans, Male, Mothers, Organophosphates, Young Adult

BACKGROUND: Humans are ubiquitously exposed to flame retardants, including organophosphate esters (OPEs), through direct contact with consumer products or exposure through household dust. Children are at increased risk because of their proximity to dust, hand-to-mouth activity, and the importance of childhood as a critical period in neurodevelopment.

OBJECTIVES: To quantify differences in exposure levels between mothers and children (three to six years of age), we analyzed urinary metabolites of OPEs. We additionally assessed the ability of silicone wristbands (measuring ambient exposure) to predict urinary metabolite concentrations.

METHODS: We selected 32 mother and child dyads from an existing cohort. Participants provided baseline urine samples and wore wristbands for one week. After the first week, they returned their wristbands and provided a second urine sample. During the second week, participants wore a second wristband that they returned at the end of week two with a third and final urine sample.

RESULTS: We found significantly higher levels of bis(1,3-dichloro-2-propyl) phosphate (BDCIPP) (p < 0.001) and lower levels of bis(1-chloro-2-isopropyl) 1-hydroxy-2-propyl phosphate (BCIPHIPP) (p < 0.001) in children's urine samples compared to mothers' samples at baseline. We found that triphenylphosphate (TPHP), tris(1,3-dichloroisopropyl) phosphate (TDCIPP), and tris(1-chloro-2-propyl) phosphate (TCIPP) measured in wristbands predicted their respective metabolite levels in urine.

CONCLUSION: Children had higher levels than mothers for two of six flame retardant metabolites measured in urine. Generally, wristband measurements positively predicted internal dose. As little is known about the health effects of OPEs on child development, future research is needed to determine the impact of differential exposure.

Alternate JournalChemosphere
PubMed ID30553217
PubMed Central IDPMC6460923
Grant ListP30 ES009089 / ES / NIEHS NIH HHS / United States
R01 ES021806 / ES / NIEHS NIH HHS / United States
T32 ES007322 / ES / NIEHS NIH HHS / United States
T32 ES023772 / ES / NIEHS NIH HHS / United States
Projects Reference: 
Flame Retardants
Silicone Wristband Personal Monitoring Device