Alternative Flame Retardants Research Articles

Current levels and composition profiles of PBDEs and alternative flame retardants in surface sediments from the Pearl River Delta, southern China: Comparison with historical data

Polybrominated diphenyl ethers (PBDEs) and alternative flame retardants were measured in surface sediments collected during 2009–2010 from the Pearl River Delta, southern China (a large manufacturing base for electronics/electrical products), to evaluate the influence of China's RoHS directive (adopted in 2006) on their environmental occurrence. The concentrations in sediments from different water systems ranged from 3.67 to 2520ng/g (average of 17.1–588ng/g) for PBDEs and from 0.22 to 5270ng/g (average of 11.3–454ng/g) for the alternative retardants. Although the PBDE levels have decreased significantly compared with those in sediments collected in 2002 in this region, the levels of alternative decabromodiphenyl ethane (DBDPE) have exceeded those of BDE209 (two predominant halogenated flame retardants (HFRs) in China) in the majority of sediments. This finding suggests a different contaminant pattern of HFRs in current sediments due to the replacement of the deca-BDE mixture with DBDPE in this region. In addition, sediment concentrations of discontinued PBDEs in the rural area are clearly elevated due to e-waste dismantling. The congener profiles of PBDEs in the current sediments (with more abundant lower-brominated congeners) differed substantially from those in 2002 and from the technical products, suggesting that biological or photolytic debromination of PBDEs may have occurred in the environment.

Brominated and chlorinated flame retardants in San Francisco Bay sediments and wildlife

Restrictions on the use of polybrominated diphenyl ethers (PBDEs) have resulted in the use of alternative flame retardants in consumer products to comply with flammability standards. In contrast to PBDEs, information on the occurrence and fate of these alternative compounds in the environment is limited, particularly in the United States. In this study, a survey of flame retardants in San Francisco Bay was conducted to evaluate whether PBDE replacement chemicals and other current use flame retardants were accumulating in the Bay food web. In addition to PBDEs, brominated and chlorinated flame retardants (hexabromocyclododecane (HBCD) and Dechlorane Plus (DP)) were detected in Bay sediments and wildlife. Median concentrations of PBDEs, HBCD, and DP, respectively, were 4.3, 0.3, and 0.2ngg−1 dry weight (dw) in sediments; 1670, <6.0, and 0.5ngg−1 lipid weight (lw) in white croaker (Genyonemus lineatus); 1860, 6.5, and 1.3ngg−1 lw in shiner surfperch (Cymatogaster aggregata); 5500, 37.4, and 0.9ngg−1 lw in eggs of double-crested cormorant (Phalacrocorax auritus); 770, 7.1, and 0.9ngg−1 lw in harbor seal (Phoca vitulina) adults; and 330, 3.5, and <0.1ngg−1 lw in harbor seal (P. vitulina) pups. Two additional flame retardants, pentabromoethylbenzene (PBEB) and 1,2-bis(2,4,6 tribromophenoxy)ethane (BTBPE) were detected in sediments but with less frequency and at lower concentrations (median concentrations of 0.01 and 0.02ngg−1 dw, respectively) compared to the other flame retardants. PBEB was also detected in each of the adult harbor seals and in 83% of the pups (median concentrations 0.2 and 0.07ngg−1 lw, respectively). The flame retardants hexabromobenzene (HBB), decabromodiphenyl ethane (DBDPE), bis(2-ethylhexyl) tetrabromophthalate (TBPH), and 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (TBB), were not detected in sediments and BTBPE, HBB and TBB were not detected in wildlife samples. Elevated concentrations of some flame retardants were likely associated with urbanization and Bay hydrodynamics. Compared to other locations, concentrations of PBDEs in Bay wildlife were comparable or higher, while concentrations of the alternatives were generally lower. This study is the first to determine concentrations of PBDE replacement products and other flame retardants in San Francisco Bay, providing some of the first data on the food web occurrence of these flame retardants in a North American urbanized estuary.

Why is it So Difficult to Choose Safer Alternatives for Hazardous Chemicals?

The discovery of persistent, bioaccumulative, and toxic flame-retardant chemicals everywhere from animals north of the Arctic Circle1 to the breast milk of California women2 has bee]n a cause for considerable concern. Alternative flame retardants were introduced to replace these chemicals,3 but investigators had not even produced the first empirical data on the substitutes’ metabolic fate and toxicity before emerging evidence indicated they, like their predecessors, were accumulating rapidly in the environ-ment. As the postmarket research continues, one wonders: Who, exactly, decides on the replacements for toxic chemicals, and on the basis of what criteria? And why does finding truly safer alternatives seem so difficult?

Modulation of human α4β2 nicotinic acetylcholine receptors by brominated and halogen-free flame retardants as a measure for in vitro neurotoxicity

Brominated flame retardants (BFRs) are abundant persistent organic pollutants with well-studied toxicity. The toxicological and ecological concern associated with BFRs argues for replacement by safer alternatives. However, the (neuro)toxic potential of alternative halogen-free flame retardants (HFFRs) is unknown. Previous research identified the nervous system as a sensitive target organ for BFRs, with modulation of excitatory nicotinic acetylcholine (nACh) receptors as one of the modes of action. Since it is essential to assess the (neuro)toxic potential of HFFRs before large scale use, we measured the effects of three BFRs and 13 HFFRs on the function of human α4β2 nACh receptors, expressed in Xenopus oocytes, using the two-electrode voltage-clamp technique. The results demonstrate that some BFRs (TBBPA and to a lesser extent BDE-209) and HFFRs (TPP, Alpi, APP, MMT and to a lesser extent ATH, ATO, MHO, MPP, RDP and ZHS) act as nACh receptor antagonists. Contrary, BPS, BDP, DOPO and ZS were unable to modulate nACh receptors. Despite the lack of toxicological data on HFFRs and the need for additional studies to perform a full (neuro)toxic risk assessment, the current data on antagonistic effects on nACh receptors could be an important step in prioritizing viable HFFRs for substitution of BFRs.

Photolytic degradation of decabromodiphenyl ethane (DBDPE)

The photolytic degradation of decabromodiphenyl ethane (DBDPE), an alternative flame retardant to decabromodiphenyl ether, was investigated in a variety of matrixes (n-hexane, tetrahydrofuran, methanol/water, humic acid/water, and silica gel) by irradiation under ultraviolet light and in n-hexane under natural light. Photolytic degradation of DBDPE occurs in all the matrixes investigated within the irradiation period (<320min). The degradation experiments showed varied reaction rates, dependent on the matrixes, with increasing half-lives (t1/2) in the order of tetrahydrofuran (t1/2=6.0min)>n-hexane (t1/2=16.6min)>humic acid/water (30<t1/2<60)>silica gel (t1/2=75.9min)>methanol/water (t1/2>240min). The reaction in tetrahydrofuran, n-hexane, and silica gel matrixes can be described by the pseudo first order kinetics. Nevertheless, the matrixes have little effect on the degradation product distributions of DBDPE. A numbers of debrominated intermediates were identified. The degradation involves the initial formation of nona-BDPEs and the subsequent decomposition of these congeners to lower brominated congeners (octa- and hepta-BDPEs) within the irradiation time. To our knowledge, the present work is the first attempt to investigate the photolytic degradation kinetics and the identification of intermediates, as well as the degradation mechanism, during the degradation of DBDPE. Further research is needed to understand the photolytic degradation pattern of DBDPE in the natural environment.

Occurrence of alternative flame retardants in indoor dust from New Zealand: Indoor sources and human exposure assessment

Due to worldwide restrictions on polybrominated diphenyl ethers (PBDEs), the demand for alternative flame retardants (AFRs), such as organophosphate flame retardants (OPFRs), novel brominated FRs (NBFRs) and hexabromocyclododecanes (HBCDs), has recently increased. Little is known about human exposure to NBFRs and OPFRs and that their levels in dust have been scarcely evaluated worldwide. To increase the knowledge regarding these chemicals, we measured concentrations of five major NBFRs, ten OPFRs and three HBCD isomers in indoor dust from New Zealand homes. Dust samples were taken from living room floors (n=34) and from mattresses of the same houses (n=16). Concentrations (ngg−1) of NBFRs were: 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) (<2–175), decabromodiphenyl ethane (DBDPE) (<5–1430), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB) (<2–2285) and bis(2-ethylhexyl)-3,4,5,6-tetrabromophthalate (TBPH) (<2–640). For OPFRs, concentrations (ngg−1) ranged between: tri-ethyl-phosphate (TEP) (<10–235), tri-n-butyl-phosphate (TnBP) (<20–7545), tris-(2-chloroethyl)-phosphate (TCEP) (<20–7605), tris-(1-chloro-2-propyl) phosphate (TCPP) (20–7615), tri-(2-butoxyethyl)-phosphate (TBEP) (50–27325), tris-(2,3-dichloropropyl)-phosphate (TDCPP) (20–16560), tri-phenyl-phosphate (TPhP) (20–35190), and tri-cresyl-phosphate (TCP) (<50–3760). HBCD concentrations fell in the range <2–4100ngg−1. BTBPE, DBDPE, TBPH, TBEP, and TnBP showed significant positive correlation (p<0.05) between their concentrations in mattresses and the corresponding floor dust (n=16). These data were used to derive a range of plausible exposure scenarios. Although the estimated exposure is well below the corresponding reference doses (RfDs), caution is needed given the likely future increase in use of these FRs and the currently unknown contribution to human exposure by other pathways such as inhalation and diet.

Hormonal activities of new brominated flame retardants

After the phase-out of two commercial mixtures of brominated flame retardants, an increasing number of alternative flame retardants have been introduced in commercial applications. None of them, however, has been thoroughly tested for its hormonal activity. We used two yeast reporter-gene assays to determine the potential of eleven compounds to interfere with estrogenic and androgenic pathways. Our data demonstrate the ability of 2,4,6-tribromophenol to lower the transcriptional activity of human estrogen and androgen receptors. A nominal IC50 value of 14.1μM for anti-estrogenic and 3.9μM for anti-androgenic activity was obtained using the luciferase reporter. An IC50 value of 9.2μM was calculated for the anti-estrogenic activity measured by the β-galactosidase assay. Of the tested chemicals, this study highlights the endocrine disrupting effects of 2,4,6-tribromophenol whose occurrence in the environment should be monitored.

Halogen-free ultra-high flame retardant polymers through enzyme catalysis

Over the past few years, the use of certain types of halogenated flame retardant additives such as decabromodiphenylether has come under intense scrutiny due to their toxicity, environmental persistence and bio-accumulation. There is an immediate need for the development of non-toxic alternative flame retardant materials and fire resistant polymers with comparable or better efficacies, obtained using benign synthetic approaches. Enzymatic polymerization is being used increasingly as an environmentally friendly alternative method for the synthesis of functional materials including polymers and additives. Here, we report a biocatalytic synthesis of a new class of thermally stable, ultra-fire resistant polyphenols based on deoxybenzoins. In calorimetric studies, these polyphenols exhibit very low heat release capacities (comparable to Nomex™) and form a large amount of carbonaceous char rendering them suitable for flame retardant applications.

Measurement of flame retardants and triclosan in municipal sewage sludge and biosolids

As polybrominated diphenyl ethers (PBDEs) face increasing restrictions worldwide, several alternate flame retardants are expected to see increased use as replacement compounds in consumer products. Chemical analysis of biosolids collected from wastewater treatment plants (WWTPs) can help determine whether these flame retardants are migrating from the indoor environment to the outdoor environment, where little is known about their ultimate fate and effects. The objective of this study was to measure concentrations of a suite of flame retardants, and the antimicrobial compound triclosan, in opportunistic samples of municipal biosolids and the domestic sludge Standard Reference Material (SRM) 2781. Grab samples of biosolids were collected from two WWTPs in North Carolina and two in California. Biosolids samples were also obtained during three subsequent collection events at one of the North Carolina WWTPs to evaluate fluctuations in contaminant levels within a given facility over a period of three years. The biosolids and SRM 2781 were analyzed for PBDEs, hexabromobenzene (HBB), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (TBB), di(2-ethylhexyl)-2,3,4,5-tetrabromophthalate (TBPH), the chlorinated flame retardant Dechlorane Plus (syn- and anti-isomers), and the antimicrobial agent 5-chloro-2-(2,4-dichlorophenoxy)phenol (triclosan). PBDEs were detected in every sample analyzed, and ΣPBDE concentrations ranged from 1750 to 6358ng/g dry weight. Additionally, the PBDE replacement chemicals TBB and TBPH were detected at concentrations ranging from 120 to 3749ng/g dry weight and from 206 to 1631ng/g dry weight, respectively. Triclosan concentrations ranged from 490 to 13,866ng/g dry weight. The detection of these contaminants of emerging concern in biosolids suggests that these chemicals have the potential to migrate out of consumer products and enter the outdoor environment.

Brominated and organophosphate flame retardants in selected consumer products on the Japanese market in 2008

The concentrations of traditional brominated flame retardants (BFRs) and organophosphate flame retardants (OPFRs) in new consumer products, including electronic equipment, curtains, wallpaper, and building materials, on the Japanese market in 2008 were investigated. Although some components of the electronic equipment contained bromine at concentrations on the order of percent by weight, as indicated by X-ray fluorescence analysis, the bromine content could not be fully accounted for by the BFRs analyzed in this study, which included polybrominated diphenylethers, decabromodiphenyl ethane, tetrabromobisphenol A, polybromophenols, and hexabromocyclododecanes. These results suggest the use of alternative BFRs such as newly developed formulations derived from tribromophenol, tetrabromobisphenol A, or both. Among the 11 OPFRs analyzed, triphenylphosphate was present at the highest concentrations in all the products investigated, which suggests the use of condensed-type OPFRs as alternative flame retardants, because they contain triphenylphosphate as an impurity. Tripropylphosphate was not detected in any samples; and trimethylphosphate, tributyl tris(2-butoxyethyl)phosphate, and tris(1,3-dichloro-2-propyl)phosphate were detected in only some components and at low concentrations. Note that all the consumer products evaluated in this study also contained traditional BFRs in amounts that were inadequate to impart flame retardancy, which implies the incorporation of recycled plastic materials containing BFRs that are of global concern.

Identification of Flame Retardants in Polyurethane Foam Collected from Baby Products

With the phase-out of PentaBDE in 2004, alternative flame retardants are being used in polyurethane foam to meet flammability standards. However, insufficient information is available on the identity of the flame retardants currently in use. Baby products containing polyurethane foam must meet California state furniture flammability standards, which likely affects the use of flame retardants in baby products throughout the U.S. However, it is unclear which products contain flame retardants and at what concentrations. In this study we surveyed baby products containing polyurethane foam to investigate how often flame retardants were used in these products. Information on when the products were purchased and whether they contained a label indicating that the product meets requirements for a California flammability standard were recorded. When possible, we identified the flame retardants being used and their concentrations in the foam. Foam samples collected from 101 commonly used baby products were analyzed. Eighty samples contained an identifiable flame retardant additive, and all but one of these was either chlorinated or brominated. The most common flame retardant detected was tris(1,3-dichloroisopropyl) phosphate (TDCPP; detection frequency 36%), followed by components typically found in the Firemaster550 commercial mixture (detection frequency 17%). Five samples contained PBDE congeners commonly associated with PentaBDE, suggesting products with PentaBDE are still in-use. Two chlorinated organophosphate flame retardants (OPFRs) not previously documented in the environment were also identified, one of which is commercially sold as V6 (detection frequency 15%) and contains tris(2-chloroethyl) phosphate (TCEP) as an impurity. As an addition to this study, we used a portable X-ray fluorescence (XRF) analyzer to estimate the bromine and chlorine content of the foam and investigate whether XRF is a useful method for predicting the presence of halogenated flame retardant additives in these products. A significant correlation was observed for bromine; however, there was no significant relationship observed for chlorine. To the authors knowledge, this is the first study to report on flame retardants in baby products. In addition, we have identified two chlorinated OPFRs not previously documented in the environment or in consumer products. Based on exposure estimates conducted by the Consumer Product Safety Commission (CPSC), we predict that infants may receive greater exposure to TDCPP from these products compared to the average child or adult from upholstered furniture, all of which are higher than acceptable daily intake levels of TDCPP set by the CPSC. Future studies are therefore warranted to specifically measure infants exposure to these flame retardants from intimate contact with these products and to determine if there are any associated health concerns.

Polybrominated diphenyl ethers (PBDEs) and alternative brominated flame retardants in air and seawater of the European Arctic

The spatial distribution of polybrominated diphenyl ethers (PBDEs) and several alternative non-PBDE, non-regulated brominated flame retardants (BFRs) in air and seawater and the air–seawater exchange was investigated in East Greenland Sea using high-volume air and water samples. Total PBDE concentrations (Ó 10PBDEs) ranged from 0.09 to 1.8 pg m −3 in the atmosphere and from 0.03 to 0.64 pg L −1 in seawater. Two alternative BFRs, Hexabromobenzene (HBB) and 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE), showed similar concentrations and spatial trends as PBDEs. The air–seawater gas exchange was dominated by deposition with fluxes up to −492 and −1044 pg m −2 day −1 for BDE-47 and DPTE, respectively. This study shows the first occurrence of HBB, DPTE and other alternative flame retardants (e.g., pentabromotoluene (PBT)) in the Arctic atmosphere and seawater indicating that they have a similar long-range atmospheric transport potential (LRAT) as the banned PBDEs.

可搬型蛍光Ｘ線分析計による各種製品部材中ＲｏＨＳ指令対象物質のスクリーニング調査

The content of hazardous substances restricted by the European Union directive on the restriction of the use of certain hazardous substances in electrical and electronic equipment 2002/95/EC (RoHS directive) in various consumer products including electrical and electronic equipments (EEE), household products, recycled products etc. were analyzed by using a handheld X-ray fluorescence (XRF) analyzer. Among 358 products investigated, one third failed RoHS compliance for Br when assuming all Br derived from polybrominated biphenyls and/or polybrominated diphenyl ethers (PBDEs), and all passed the RoHS threshold for Hg levels. About half of EEE examined contained more than 0.1 wt% of Br with the maximum concentration of approximately 20 wt% in rear casing of a computer monitor, indicating some sort of brominated flame retardants (BFRs) were intentionally added. From the XRF analysis of chassis of televisions (TV) and personal computer (PC) monitors, it was revealed that the percentage of products which exceeded Br thresholds in liquid crystal display TVs and PC monitors were less than those in cathode-ray tube TVs and PC monitors, suggesting the shift of type of flame retardants used over time. As use of PBDEs was restricted by RoHS directive in 2006, the consumer-electronics makers started using alternative flame retardants including novel non-PBDE BFRs and phosphorus flame retardants as well.

Advances in the study of current-use non-PBDE brominated flame retardants and dechlorane plus in the environment and humans

The fate of the high production volume, currently in use, and not regulated non-polybrominated diphenyl ether (PBDE) flame retardants, such as tetrabromobisphenol A (TBBPA), hexabromocyclododecane (HBCD) and dechlorane plus (DP), and the alternative flame retardants of PBDE, such as BTBPE and DBDPE, in the environment has attracted increasing attention and aroused concern due to the increasing regulation and phasing-out of PBDEs. This paper reviews the distribution, bioaccumulation, human exposure and environmental behavior of those non-PBDE flame retardants in various environmental compartments. The data gaps and needs for future research are discussed.

Flame retardant challenges for textiles and fibres: New chemistry versus innovatory solutions

Almost 50 years ago, the 1950–1960 period witnessed the development of the chemistry underlying most of today’s successful and durable flame retardant treatments for fibres and textiles. In today’s more critical markets in terms of environmental sustainability, chemical toxicological acceptability, performance and cost, many of these are now being questioned. “Are there potential replacements for established, durable formaldehyde-based flame retardants such as those based on tetrakis (hydroxylmethyl) phosphonium salt and alkyl-substituted, N-methylol phosphonopropionamide chemistries for cellulosic textiles?” is an often-asked question. “Can we produce char-forming polyester flame retardants?” and “Can we really produce effective halogen-free replacements for coatings and back-coated textiles?” are others. These questions are addressed initially as a historical review of research undertaken in the second half of the twentieth century which is the basis of most currently available, commercialised flame retardant fibres and textiles. Research reported during the first decade of the twenty first century and which primarily addresses the current issues of environmental sustainability and the search for alternative flame retardant solutions, the need to increase char-forming character in synthetic fibres and the current interest in nanotechnology is critically discussed. The possible roles of micro- and nano-surface treatments of fibre surfaces and their development using techniques such as plasma technology are also reviewed.

Endocrine Damper? Flame Retardants Linked to Male Hormone, Sperm Count Changes

Additive flame retardants such as tris(1,3-dichloro-2-propyl) phosphate (TDCPP) and triphenyl phosphate (TPP), which are not chemically bonded to the products they are intended to protect, may escape into indoor environments such as homes, offices, and car interiors. A new study shows that men living in homes with higher amounts of TCDPP and TPP in their house dust had reduced sperm counts and altered levels of hormones related to fertility and thyroid function [EHP 118:318–323; Meeker and Stapleton]. Because the research to date suggests both compounds are ubiquitous in U.S. homes, the study points to a pressing need for further investigation into the sources and levels of day-to-day exposure to the compounds as well as their potential health effects. TDCPP has long been the main flame retardant used in automotive foam cushioning, while TPP has been used for decades in a wide variety of applications, including furniture foam. Since polybrominated diphenyl ether (PBDE) flame retardants were banned in Europe and discontinued in the United States in 2004, the use of alternative flame retardants such as TDCPP and TPP has been on the rise. Indoor dust is known to be an important source of exposure to PBDEs (which also are additive compounds), and the authors suspect this could also be true for other flame retardants. In the current study, TDCPP was found in 96% and TPP in 98% of the house dust samples. As has been reported for other flame retardants found in house dust, the concentrations of the flame retardants in the samples varied markedly, with ranges of < 107–56,090 ng/g for TDCPP and < 173–1,798,100 ng/g for TPP. The concentrations of TDCPP in the men’s homes were comparable to those of PBDEs, whereas the levels of TPP were considerably higher. Because the study participants were part of a larger project involving men recruited from a Boston infertility clinic, the authors had access to information about the men’s reproductive and thyroid hormone levels as well as their semen quality. They estimated associations for an interquartile range (IQR) increase in the level of each chemical measured in the dust samples, adjusting for potential confounders such as age and body mass. IQR analyses reflect the difference between the concentrations at the highest and lowest ends of the middle 50% of exposures. This analysis revealed that each IQR TPP increase in the homes was associated with a 19% decrease in sperm concentrations and a 10% increase in prolactin levels. Increased prolactin can be a marker of decreased dopamine activity and also may be associated with erectile dysfunction. The authors also found that each IQR increase in TDCPP in the homes was associated with a 17% increase in prolactin and a 3% decline in free levels of the thyroid hormone thyroxine. The findings mirror the limited toxicology data available on the study’s end points. They are also consistent with findings on other organophosphate compounds such as the urinary metabolite of the insecticide chlorpyrifos [EHP 112:1665–1670; Meeker et al.]. The authors hope to follow up by exploring human exposure pathways for these flame retardant chemicals and by reassessing these relationships with markers of endocrine function among a greater number of men from the larger ongoing study.

PBDEs in Diet: Meat Fat a Leading Source

Vol. 117, No. 10 NewsOpen AccessPBDEs in Diet: Meat Fat a Leading Source Naomi Lubick Naomi Lubick Search for more papers by this author Published:1 October 2009https://doi.org/10.1289/ehp.117-a455bAboutSectionsPDF ToolsDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InReddit Although researchers have long known polybrominated diphenyl ethers (PBDEs) appear in foods such as beef, chicken, fish, and milk, the results of a new study are the first to link blood levels of prevalent PBDEs with food intake over a wide population [EHP117:1520–1525; Fraser et al.]. Researchers from the Boston University School of Public Health examined data from the 2003–2004 National Health and Nutrition Examination Survey (NHANES) and found that people who reported eating the most poultry and beef had higher average serum PBDE levels than people who ate lower amounts of these meats.PBDEs are used as flame retardants for electronics, fabrics, packing materials, and other products. Some of the formulations that trigger the most concern—for example, penta‐BDE, which contains BDE‐28, ‐47, ‐99, ‐100, and ‐153—are no longer produced in Europe and the United States, but persistent PBDEs remain in such items as older electronics and upholstered furniture, and often turn up in household dust. Past surveys have found high levels of these compounds in human tissues. Fat‐soluble and persistent, PBDEs cause numerous adverse health effects in experimental animals and are suspected endocrine disruptors in humans.The study included NHANES participants for whom there were serum measurements of up to 10 PBDE congeners as well as information on what the participants had eaten the day before the interview and their usual diet over the past year. The researchers compared the diet survey information with the results of the blood sample analyses, which had revealed detectable levels of five PBDE congeners in more than 60% of the study population.The researchers found that, overall, vegetarians had serum PBDE concentrations approximately 25% lower than those of omnivores. The people most likely to have the highest total PBDE concentrations were young and male. Levels of all five congeners were significantly associated with high poultry fat intake. All five congeners also were associated with high intake of red meat fat, with statistically significant associations for BDE‐100, BDE‐153, and total serum PBDEs. However, the team found no significant associations between serum PBDE concentrations and high dairy or fish consumption—even though these foods also contain measurable levels of PBDEs. The authors hypothesize that although both farmed and wild fish can contain high levels of PBDEs, Americans may not consume enough fish to make this a significant source of exposure.Next steps should include measuring food intake against BDE‐209, which is not yet included in NHANES data, and direct comparisons with exposure via dust. The authors write that researchers will also have to watch for shifts in humans’ exposure—old products will remain as reservoirs for further exposure even as manufacturers move toward alternative flame retardants, which themselves may have unexpected toxic effects.FiguresReferencesRelatedDetails Vol. 117, No. 10 October 2009Metrics About Article Metrics Publication History Originally published1 October 2009Published in print1 October 2009 Financial disclosuresPDF download License information EHP is an open-access journal published with support from the National Institute of Environmental Health Sciences, National Institutes of Health. All content is public domain unless otherwise noted. Note to readers with disabilities EHP strives to ensure that all journal content is accessible to all readers. However, some figures and Supplemental Material published in EHP articles may not conform to 508 standards due to the complexity of the information being presented. If you need assistance accessing journal content, please contact [email protected]. Our staff will work with you to assess and meet your accessibility needs within 3 working days.

Detection of Organophosphate Flame Retardants in Furniture Foam and U.S. House Dust

Restrictions on the use of polybrominated diphenyl ethers (PBDEs) have resulted in the increased use of alternate flame retardant chemicals to meet flammability standards. However, it has been difficult to determine which chemical formulations are currently being used in high volumes to meet flammability standards since the use of flame retardant formulations in consumer products is not transparent (i.e., not provided to customers). To investigate chemicals being used as replacements for PentaBDE in polyurethane foam, we analyzed foam samples from 26 different pieces of furniture purchased in the United States primarily between 2003 and 2009. Samples included foam from couches, chairs, mattress pads, pillows, and, in one case, foam from a sound-proofing system of a laboratory-grade dust sieve, and were analyzed using gas chromatography mass spectrometry. Fifteen of the foam samples contained the flame retardanttris(1,3-dichloro-2-propyl) phosphate (TDCPP; 1-5% by weight), four samples contained tris(1-chloro-2-propyl) phosphate (TCPP; 0.5 -22% by weight), one sample contained brominated chemicals found in a new flame retardant mixture called Firemaster 550 (4.2% by weight), and one foam sample collected from a futon likely purchased prior to 2004 contained PentaBDE (0.5% by weight). Due to the high frequency of detection of the chlorinated phosphate compounds in furniture foam,we analyzed extracts from 50 house dust samples collected between 2002 and 2007 in the Boston, MA area for TDCPP, TCPP, and another high volume use organophosphate-based flame retardant used in foam, triphenylphosphate (TPP). Detection frequencies for TDCPP and TPP in the dust samples were > 96% and were log normally distributed, similar to observations for PBDEs. TCPP was positively detected in dust in only 24% of the samples, but detection was significantly limited by a coelution problem. The geometric mean concentrations for TCPP, TDCPP, and TPP in house dust were 570, 1890, and 7360 ng/g, respectively, and maximum values detected in dust were 5490, 56,080 and 1,798,000 ng/g, respectively. These data suggest that levels of these organophosphate flame retardants are comparable, or in some cases greater than, levels of PBDEs in house dust. The high prevalence of these chemicals in foam and the high concentrations measured in dust (as high as 1.8 mg/g) warrant further studies to evaluate potential health effects from dust exposure, particularly for children.

Analysis and occurrence of emerging brominated flame retardants in the Llobregat River basin

Summary In response to increasing international regulations on brominated flame retardants (BFR) formulations, alternative additive flame retardants for achieving commercial product fire safety standards are being developed and used. Some of these non-BDE (brominated diphenyl ethers) BFRs are pentabromoethylbenzene (PBEB), hexabromobenzene (hexaBBz), and decabromodiphenylethane (deBDethane). The present study investigated the occurrence of these emerging BFRs, together with 38 BDE congeners (from di- to deca-BDE) in sediments sampled from different points along Llobregat basin (Spain) in three different sampling campaigns between 2005 and 2006. Emerging BFRs were detected in all sediment samples analyzed, at concentrations ranging from 3.1 to 9.6 ng/g for PBEB, from 0.4 to 2.4 ng/g for hexaBBz and from 4.8 to 23 ng/g for deBDethane. These levels are lower than concentrations obtained for PBDEs (from nd to 82 ng/g).

Clinical Facts & Curios

In order to better understand the exposure of aquatic systems to halogenated flame retardant contaminants, the present study investigated a variety of legacy and emerging flame retardants in common carp and largemouth bass collected from 58 stations across Illinois (United States). The data revealed that polybrominated diphenyl ethers (PBDEs) generally dominated the flame retardant residues in Illinois fish. Concentrations of ΣPBDEs (including all detectable PBDE congeners) ranged from 24.7 to 8270 ng/g lipid weight (median: 135 ng/g lw) in common carp and 15–3870 ng/g lw (median: 360 ng/g lw) in largemouth bass. In addition to PBDEs, Dechlorane analogues (i.e. Dec-603, Dec-604, and Chlordane Plus) were also frequently detected. Median concentrations of ΣDechloranes (including all detected Dechlorane analogues) were 34.4 and 23.3 ng/g lw in common carp and largemouth bass, respectively. Other emerging flame retardants, including tetrabromo-o-chlorotoluene (TBCT), hexabromobenzene (HBBZ), 2-ethylhexyltetrabromobenzoate (EH-TBB), and bis(2-ethylhexyl)-3,4,5,6-tetrabromo-phthalate (BEH-TEBP), were also detected in 40–78% of the fish at the monitored stations. Spatial analysis revealed significantly greater PBDE concentrations in fish living in impaired urban streams and lakes compared to those from the impaired agricultural and unimpaired agricultural/urban waters, demonstrating a significant urban influence on PBDE contamination. Future studies and environmental monitoring are recommended to focus on temporal trends of PBDEs and alternative flame retardants, as well as human exposure risks via edible fishes, in the identified Areas of Concern within Illinois.