Article pubs.acs.org/est
Halogenated Flame Retardants in Baby Food from the United States and from China and the Estimated Dietary Intakes by Infants Liang-Ying Liu, Amina Salamova, and Ronald A. Hites* School of Public and Environmental Affairs, Indiana University, Bloomington, Indiana 47405, United States S Supporting Information *
ABSTRACT: Three categories of baby food (formula, cereal, and puree) were bought from United States and Chinese stores in 2013 and analyzed for polybrominated diphenyl ethers (PBDEs) and related flame retardants. The primary goal of this project was to investigate whether there were differences in the levels of flame retardants between these two nations’ baby foods. The median concentrations of total PBDEs (sum of BDE-17, -28, -47, -49, -99, -100, -153, -183, and -209) were 21 and 36 pg/g fresh weight for the Unites States and Chinese baby foods, respectively. Among non-PBDE flame retardants, hexabromobenzene, Dechlorane Plus (DP), and decabromodiphenylethane were frequently detected (22−57%) with median concentrations of 1.6, 8.7, and 17 pg/g fresh weight for United States samples, and 1.3, 13, and 20 pg/g fresh weight for Chinese samples. In general, the flame retardant concentrations in the United States and Chinese samples were not statistically different, but very high DP concentrations were observed in one Chinese formula sample (4000 pg/g) and in one United States cereal sample (430 pg/ g), possibly suggesting contamination of the raw materials or contamination during production of these two samples. A comparison of median estimated daily dietary intake rates of BDE-47, -99, and -153 with existing reference doses for neurodevelopmental toxicity and other existing criteria suggested no concerns for the consumption of these baby foods.
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INTRODUCTION
currently usedbut unregulatedflame retardants are ubiquitous in the environment and are accumulating in biota. People are exposed to flame retardants via many pathways, among which dietary intake probably ranks second only to indoor dust ingestion.21 Thus, several studies have measured flame retardant concentrations (mainly PBDEs) in foods and have investigated their dietary intake rates.6,22,23 Infants are a particularly vulnerable population, and a previous study has indicated higher accumulation of PBDEs in infants than in adults.24 A study of the dietary intake of PBDEs as a function of age suggested that nursing infants had the highest dietary intake among eight age groups.22 The concentrations of PBDEs in human breast milk have been widely studied.8,20,25 Although human breast milk is the major food of infants, more and more mothers stop breast feeding early,26 and many infants are fed ready-to-use baby food, including infant formula; cereals; and vegetable, fruit, and meat purees. Not much is known about the flame retardant concentrations in these baby foods.3,22,27 Only three studies have measured flame retardants in baby foods. Schecter et al. analyzed PBDEs in 32 food samples in a market basket study from the United States, but only one of them was an infant formula.3 PBDEs were also measured in 62 food samples in a survey of United States foods, but only two of them were infant
Halogenated flame retardants, such as polybrominated diphenyl ethers (PBDEs) and Dechlorane Plus (DP), are persistent and bioaccumulative chemicals, which have been used as flame retardants in various commercial and household products (for example, in electronics, textiles, plastics, and polyurethane foam) to slow the spread of fire. PBDEs and DP can escape from their host materials, and they have become ubiquitous in various environmental matrixes,1,2 foods,3−6 and human tissues.7−10 Previous studies have suggested that some of these chemicals may have adverse biological effects (e.g., endocrine disruption, reproductive/developmental toxicity, neurotoxicity, and cancer) in people or in animals.11−14 Due to increasing environmental and human health concerns, the flame retardant industry voluntarily ceased production and use of PBDEs in the United States. In China, production of the Penta-BDE mixture stopped in 2004; however, Deca-BDE is still being produced and used there.15 Replacements for PBDEs, sometimes called alternative flame retardants, are now entering the environment. These replacements include Firemaster 550 [mainly 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB) and bis(2-ethylhexyl)-tetrabromophthalate (TBPH)], pentabromobenzene (PBBZ), pentabromoethylbenzene (PBEB), hexabromobenzene (HBB), decabromodiphenylethane (DBDPE), and others. Several of these alternative flame retardants have been found in various environmental matrices,16 in aquatic biota, in wildlife,16−18 in human serum,19 and in human milk.20 These studies suggest that © 2014 American Chemical Society
Received: Revised: Accepted: Published: 9812
June 5, 2014 July 17, 2014 July 21, 2014 August 1, 2014 dx.doi.org/10.1021/es502743q | Environ. Sci. Technol. 2014, 48, 9812−9818
Environmental Science & Technology
Article
formula.22 In study by Lankova et al., brominated flame retardant concentrations in 6 different infant formula samples from the Czech retail market were measured, but none of the target compounds (hydroxylated metabolites and brominated phenols) were detected in any of the samples.27 The aims of this study are to measure the levels of PBDEs, DP, and alternative flame retardants in baby food from the United States and China, to reveal the potential differences (if any) in these concentrations, and to investigate the dietary exposure of infants who consume this food. We elected to study baby food from the United States and China because of differences in food regulations and different flame retardant production and use histories. These differences may cause different flame retardant concentrations in baby foodfood which is consumed by large infant populations in these two countries.
ration, Bellefonte, CA). Detailed information on the GC/MS methods can be found elsewhere.28 Quality Assurance and Quality Control. One procedural blank and one matrix spike recovery sample were processed along with each set of 6 samples. The recoveries for matrix spike samples ranged from 80 ± 13% for BDE-209 to 103 ± 16% for BDE-49. The recoveries for the surrogate recovery standards for all samples were 97 ± 13%, 86 ± 10%, and 64 ± 14%, for BDE-77, BDE-166, and 13C12-BDE-209, respectively. Average concentrations in procedural blanks ranged from 0.20 pg/g for BDE-17 to 7.9 pg/g for DBDPE, when normalized to an average sample weight of 10 g. Data Analysis. Any concentrations less than twice the procedural blank levels were treated as nondetects and were not included in the statistical analysis. Fresh weight rather than lipid weight normalized concentrations are reported unless specified because fresh weight based concentrations are the most useful in the calculation of dietary intake. Log-transformed concentration data for each category of baby food were subject to an ANOVA (Minitab 16.0) to investigate any potential differences in flame retardants levels among the United States and Chinese samples. Dietary Intake and Health Risk Assessment. Daily dietary intake rates (in ng/day) were calculated for each compound by multiplying the concentration of that compound (pg/g) by the consumption rate of that food (g/day). Daily dietary intake rates were calculated for babies aged 1−12 months, subgrouped into 1−2, 3−4, 5−6, and 7−12 month age categories. Only formula and cereal were taken into account because these two foods are the most common foods for
