Polybrominated Diphenyl Ethers, Polychlorinated Biphenyls, and 2,2-Bis(4-chlorophenyl)-1,1-dichloroethene in 7- and 9‑Year-Old Children and Their Mothers in the Center for the Health Assessment of Mothers and Children of Salinas Cohort

We report longitudinal serum concentrations of select persistent organic pollutants (POPs) in children at ages 7 and 9 years and in their mothers prenatally and again when the children were 9 years old. The participating families were enrolled in the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS), a longitudinal birth cohort study of low-income Hispanic families residing in the Salinas Valley, California. We observed decreasing concentrations in the mothers with year of serum collection (2009 vs 2011) for six out of seven polybrominated diphenyl ether (PBDE) congeners and for 2,2′,4,4′,5-pentachlorobiphenyl (CB-99; <i>p</i> < 0.05). The 9-year-old children had similarly decreasing serum concentrations of all seven PBDE congeners, CB-99, and 2,2′,3,4,4′,5′- and 2,3,3′,4,4′,6-hexachlorobiphenyl (CB-138/158) with year of serum collection (2009 vs 2011; <i>p</i> < 0.05). In mixed effect models accounting for weight gain as the children aged from 7 to 9 years, we observed an annual decrease (−8.3% to −13.4%) in tri- to hexaBDE concentrations (<i>p</i> < 0.001), except for 2,2′,3,4,4′-tetrabromodiphenyl ether (BDE-85) and 2,2′,4,4′,5,5′-hexabromodiphenyl ether (BDE-153). The concentrations of these congeners were not associated with time of serum collection and instead showed an −0.9% to −2.6% decrease per kilogram of weight gain during the study period (<i>p</i> < 0.05). In the case of tetra- to heptachlorobiphenyls, we observed −0.5% to −0.7% decrease in serum concentration per kilogram of weight gain (<i>p</i> < 0.05) and −3.0% to −3.7% decrease in serum concentration per year of aging (<i>p</i> < 0.05), except for 2,3′,4,4′,5-pentachlorobiphenyl (CB-118) and 2,2′,4,4′,5,5′-hexachlorobiphenyl (CB-153), which were not associated with time of serum draw. 2,2-Bis­(4-chlorophenyl)-1,1-dichloroethene (<i>p</i>,<i>p</i>′-DDE) decreased −2.4%/kg of weight gain between the two sampling points (<i>p</i> < 0.001). These findings suggest that as children grow, dilution in a larger body size plays an important role in explaining reductions in body burden in the case of traditional POPs such as PCBs and <i>p</i>,<i>p</i>′-DDE. By contrast, in the case of PBDEs, reductions are likely explained by reduction in exposure, as illustrated by decreased concentrations in more recent years, possibly amplified by presumed shorter biological half-life than other POPs

Polybrominated Diphenyl Ethers, Polychlorinated Biphenyls, and Persistent Pesticides in Serum from the National Health and Nutrition Examination Survey: 2003–2008

Polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), and persistent pesticides have been measured in pooled samples representative of the general noninstitutionalized population of the United States. The pools were made from individual sera from the National Health and Nutrition Examination Survey (NHANES) during 2005/06 and 2007/08. The pooled concentrations have been contrasted to NHANES 2003/04 individual measurements to evaluate changes in concentration over time and within survey period differences among age groups, race/ethnicity groups (Mexican American, non-Hispanic Black, non-Hispanic White), and sex. The arithmetic mean serum concentrations of several PCB congeners decreased from NHANES 2003/04 through 2007/08. Larger percentage reductions were seen for younger subjects (12–19 years) compared with older subjects (≥60 years). For example, the arithmetic mean concentration of 2,2′,4,4′,5,5′-hexachlorobiphenyl (PCB-153) was 36% lower in 12–19 year old adolescents when comparing NHANES 2007/08 with 2003/04; while for subjects over the age of 60 a 14% lower concentration was seen, although, the 95% confidence intervals overlapped. Similarly, the arithmetic mean serum concentrations of tri- to hexaBDEs were lower in NHANES 2007/08 than in 2003/04; however, most confidence intervals of the arithmetic means overlapped. These findings suggest that a reduction in PBDE serum concentrations cannot yet be detected following the discontinuation of pentaBDE in 2004

Polybrominated Diphenyl Ethers and Other Persistent Organic Pollutants in Serum Pools from the National Health and Nutrition Examination Survey: 2001–2002

Polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), and persistent pesticides have been measured in serum pools from participants 3–5, 6–11, 12–19, 20–39, 40–59, and ≥60 years of age from the 2001–2002 National Health and Nutrition Examination Survey. For 2,2′,4,4′-tetrabromodiphenyl ether (PBDE-47), the unweighted (not adjusted for sampling weights) arithmetic mean concentration (±95% confidence interval) was 3.4 times higher in 3–5-year-olds (216 ± 30 ng/g of lipid) than in 12–19-year-olds (64 ± 11 ng/g of lipid), with no apparent change with increasing age for adults ≥20 years of age. By contrast, unweighted arithmetic mean concentrations of traditional persistent organic pollutants (POPs) such as hexachlorobenzene (HCB) and 2,2′,3,3′,4,4′,5,5′-octachlorobiphenyl (PCB194) were 2- and 20-fold higher, respectively, in persons ≥60 years than in 12–19-year-old adolescents. Findings suggest higher exposures to PBDEs but lower exposures to traditional POPs in 3–5-year-old children than in adults

Factors Associated with Serum Polybrominated Diphenyl Ether (PBDE) Levels Among School-Age Children in the CHAMACOS Cohort

Polybrominated diphenyl ethers (PBDEs) are a class of flame retardants historically used in textiles, furniture, and electronic products. Recent studies have documented widespread PBDE exposure to humans, with higher levels measured in children than adults. We analyzed 10 tri- to hepta-BDE congener levels in blood collected from 7-year old Mexican-American children living in an agriculture community in California (<i>n</i> = 272). The most frequently detected PBDE congeners in child serum were BDE-47, -99, -100, and -153, all of which were measured in >99% of the children. We used multiple linear regression models to examine associations between child total PBDE levels (ng/g lipid) and determinants of exposure. Factors positively associated with higher PBDE levels in the children were total PBDE levels in maternal serum during pregnancy, duration of exclusive breastfeeding, and having no safe places to play in their neighborhood. Child BMI was inversely associated with serum PBDE levels (regression p-values <0.05). Our findings confirm that exposure to the penta-BDE mixture is ongoing, and that Mexican-American children living in California may be experiencing higher PBDE exposure from their environment compared to children sampled from the general U.S. population. Additional research is needed to assess the health impacts of these exposures