Polybrominated Diphenyl Ether (PBDE) Levels in an Expanded Market Basket Survey of U.S. Food and Estimated PBDE Dietary Intake by Age and Sex

Article excerpt

OBJECTIVES: Our objectives in this study were to expand a previously reported U.S. market basket survey using a larger sample size and to estimate levels of PBDE intake from food for the U.S. general population by sex and age.

METHODS: We measured concentrations of 13 polybrominated diphenyl ether (PBDE) congeners in food in 62 food samples. In addition, we estimated levels of PBDE intake from food for the U.S. general population by age (birth through [greater than or equal to] 60 years of age) and sex.

RESULTS: In food samples, concentrations of total PBDEs varied from 7.9 pg/g (parts per trillion) in milk to 3,726 pg/g in canned sardines. Fish were highest in PBDEs (mean, 1,120 pg/g; median, 616 pg/g; range, 11.14-3,726 pg/g). This was followed by meat (mean, 383 pg/g; median, 190 pg/g; range, 39-1,426 pg/g) and dairy products (mean, 116 pg/g; median, 32.2 pg/g; range, 7.9-683 pg/g). However, using estimates for food consumption (excluding nursing infants), meat accounted for the highest U.S. dietary PBDE intake, followed by dairy and fish, with almost equal contributions. Adult females had lower dietary intake of PBDEs than did adult males, based on body weight. We estimated PBDE intake from food to be 307 ng/kg/day for nursing infants and from 2 ng/kg/day at 2-5 years of age for both males and females to 0.9 ng/kg/day in adult females.

CONCLUSION: Dietary exposure alone does not appear to account for the very high body burdens measured. The indoor environment (dust, air) may play an important role in PBDE body burdens in addition to food.

KEY WORDS: age, dietary intake, market basket survey, PBDEs, polybrominated diphenyl ethers, sex. Environ Health Perspect 114:1515-1520 (2006). doi:10.1289/ehp.9121 available via http://dx.doi.org/[Online 13 July 2006]

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Polybrominated diphenyl ethers (PBDEs), persistent and bioaccumulative flame retardants, are of concern because they are ubiquitous in the United States, are potentially toxic, and have been found at rapidly rising levels in humans during the past few decades (Birnbaum and Staskal 2004; Hites 2004; Schecter et al. 2005b; Sjodin et al. 2004; Webster et al. 2005). The high level of PBDE contamination in the U.S. population and food is cause for concern because these compounds are chemically similar to polychlorinated biphenyls (PCBs) and have been shown in laboratory animal studies to be toxic in a number of ways. These include cancer in high-dose studies [National Toxicology Program (NTP) 1986], reproductive and developmental toxicity (Stoker et al. 2004), endocrine disruption (Hallgren and Darnerud 2002), and central nervous system effects (Eriksson et al. 2002; Viberg et al. 2003). PBDEs can be found in some textiles, electronics, (e.g., computers, televisions), plastics, and furniture such as sofas, chairs, and mattresses. Unlike dioxins and PCBs, these chemicals are primarily indoor pollutants and are found at high levels in household vacuum dust and other home and workplace environmental samples (Schecter et al. 2005a; Stapleton et al. 2005).

Very high levels of PBDEs have recently been found in the United States in mothers' milk (Schecter et al. 2003, 2005b), blood (Mazdai et al. 2003; Morland et al. 2005; Schecter et al. 2004, 2005b; Sjodin et al. 2004), food (Schecter et al. 2004), and adipose tissue (Johnson-Restrepo et al. 2005; She et al. 2002). U.S. blood and milk concentrations were 10-to 20-fold higher than the levels found in Europe (Bocio et al. 2003; Meironyte et al. 1999; Noren and Meironyte2000; Ohta et al. 2002). Although levels of dioxins, dibenzofurans, and PCBs in human tissues are declining, PBDEs have been increasing substantially in blood levels in the United States during the past two to three decades (Schecter et al. 2005b; Sjodin et al. 2004).

The penta-BDE and octa-BDE commercial PBDE mixtures are no longer being produced or sold in the United States, whereas deca-BDE continues to be manufactured and sold in the United States as well as worldwide. …