Prenatal exposure to replacement flame retardants and organophosphate esters and childhood adverse respiratory outcomes.

BACKGROUND: The association of prenatal exposure to organophosphate esters (OPEs) and replacement brominated flame retardants (RBFRs) with respiratory outcomes has not been previously investigated in humans, despite reports that these chemicals can cross the placenta and alter lung development as well as immune functions. METHODS: In a cohort of 342 pregnant women recruited between 2003 and 2006 in the greater Cincinnati, Ohio Metropolitan area, we measured indoor dust OPEs and RBFRs at 20 weeks of gestation and urinary OPEs at 16 and 26 weeks of gestation and at delivery. We performed generalized estimating equations and linear mixed models adjusting for covariates to determine the associations of prenatal OPEs and RBFRs exposures with adverse respiratory outcomes in childhood, reported every six months until age 5 years and with lung function at age 5 years. We used multiple informant modeling to examine time-specific associations between maternal urinary OPEs and the outcomes. RESULTS: Dust concentrations of triphenyl phosphate (TPHP) (RR: 1.40, 95% CI: 1.18-1.66), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (RR: 1.51, 95% CI: 1.23-1.85), and bis(2-ethylhexyl) tetrabromophthalate (RR: 1.57, 95% CI: 1.28-1.94) were associated with higher risk of wheezing during childhood. Dust TPHP concentrations were associated with higher risk of respiratory infections (RR: 1.43, 95% CI: 1.08-1.94), and dust tris-(2-chloroethyl) phosphate concentrations were associated with hay fever/allergies (RR: 1.11, 95% CI: 1.01-1.21). We also found that dust tris-(2-chloroethyl) phosphate loadings were associated with lower lung function. Urinary OPEs mainly at week 16 of gestation tended to be associated with adverse respiratory outcome, while bis(1-chloro-2-propyl) phosphate and diphenyl phosphate at delivery were associated with lower risk of hay fever/allergies. CONCLUSIONS: In-utero exposure to OPEs and RBFRs may be a risk factor for adverse respiratory outcomes in childhood, depending on the timing of exposure.

Exposure to dust organophosphate and replacement brominated flame retardants during infancy and risk of subsequent adverse respiratory outcomes.

BACKGROUND: Children are highly exposed to flame retardants in indoor environments, partly through inhalation. However, the associations of early life exposure to novel organophosphate (OPFRs) and replacement brominated flame retardants (RBFRs) with adverse respiratory outcomes during childhood are unclear. METHODS: We used a prospective birth cohort of 234 children recruited from the greater Cincinnati, Ohio metropolitan area between 2003 and 2006. OPFRs and RBFRs were analyzed in dust sampled from the homes' main activity room and the children's bedroom floor at child age 1 year. Caregivers reported subsequent respiratory symptoms every six months until child age 5 years and we measured forced expiratory volume in 1 s as well as peak expiratory flow (PEF) at child age 5 years. We performed generalized estimating equations and linear regression modeling adjusted for covariates to examine the exposure-outcome associations. RESULTS: Geometric means (GMs) (standard error [SE]) for dust concentrations were 10.27 (0.63) µg/g for total OPFRs (ΣOPFRs) and 0.48 (0.04) µg/g for total RBFRs (ΣRBFRs); GMs (SE) for dust loadings were 2.82 (0.26) µg/m2 for ΣOPFRs and 0.13 (0.01) µg/m2 for ΣRBFRs. Dust ∑OPFRs concentrations at age 1 year were associated with higher subsequent risks of wheezing (relative risk [RR]: 1.68, 95% confidence interval [CI]: 1.20-2.34), respiratory infections (RR: 4.01, 95% CI: 1.95-8.24), and hay fever/allergies (RR: 1.33, 95% CI: 1.10-1.60), whereas ∑OPFRs dust loadings at age 1 year were associated with higher risks of subsequent respiratory infections (RR: 1.87, 95% CI: 1.05-3.34) and hay fever/allergies (RR: 1.34, 95% CI: 1.19-1.51). PEF (mL/min) was lower with higher ∑OPFRs dust loadings (ß: -12.10, 95% CI: -21.10, -3.10) and with the RBFR bis(2-ethylhexyl) tetrabromophthalate (ß: -9.05, 95% CI: -17.67, -0.43). CONCLUSIONS: Exposure to OPFRs and RBFRs during infancy may be a risk factor for adverse respiratory outcomes during childhood.

Organophosphate esters in a cohort of pregnant women: Variability and predictors of exposure.

Organophosphate esters (OPEs) are a group of chemicals used as flame retardants and plasticizers that replaced polybrominated diphenyl ethers in consumer products such as furniture and electronics. To characterize exposure to OPEs during fetal development, we measured urinary OPE metabolite concentrations in women twice during pregnancy (16 and 26 weeks' gestation) and at delivery (n = 357). We also previously quantified house dust OPE parent compound concentrations at 20 weeks' gestation (n = 317). Diphenyl phosphate (DPHP) had the highest geometric mean urinary concentrations (1.5-2.3 µg/g creatinine), followed by bis(1,3-dichloro-2-propyl) phosphate (BDCIPP; 0.75-0.99 µg/g creatinine), and bis(2-chloroethyl) phosphate (BCEP; 0.72-0.97 µg/g creatinine), while dibutyl phosphate (DNBP) had the lowest concentrations (0.25-0.28 µg/g creatinine). Urinary OPE metabolites were moderately correlated with each other at 26 weeks (rs: 0.23-0.38, p < 0.001) while the correlations at 16 weeks and delivery were slightly weaker. Intra-class correlations for urinary metabolites measured at three time points were poor (0.16-0.34), indicating high variability within individuals. Dust concentrations of OPE parent compounds were associated with BCEP, BDCIPP, and DPHP concentrations in urine at some but not all time points. In linear mixed models of urinary OPE metabolite concentrations, household size was inversely associated with BCEP concentrations, and being non-white was associated with lower BDCIPP and DPHP concentrations. Urine samples collected in the summer had the highest OPE metabolite concentrations. This study highlights the need to collect multiple urine samples during pregnancy to define exposure patterns and investigate potential periods of susceptibility.

Firefighter hood contamination: Efficiency of laundering to remove PAHs and FRs.

Firefighters are occupationally exposed to products of combustion containing polycyclic aromatic hydrocarbons (PAHs) and flame retardants (FRs), potentially contributing to their increased risk for certain cancers. Personal protective equipment (PPE), including firefighter hoods, helps to reduce firefighters' exposure to toxic substances during fire responses by providing a layer of material on which contaminants deposit prior to reaching the firefighters skin. However, over time hoods that retain some contamination may actually contribute to firefighters' systemic dose. We investigated the effectiveness of laundering to reduce or remove contamination on the hoods, specifically PAHs and three classes of FRs: polybrominated diphenyl ethers (PBDEs), non-PBDE flame retardants (NPBFRs), and organophosphate flame retardants (OPFRs). Participants in the study were grouped into crews of 12 firefighters who worked in pairs by job assignment while responding to controlled fires in a single-family residential structure. For each pair of firefighters, one hood was laundered after every scenario and one was not. Bulk samples of the routinely laundered and unlaundered hoods from five pairs of firefighters were collected and analyzed. Residual levels of OPFRs, NPBFRs, and PAHs were lower in the routinely laundered hoods, with total levels of each class of chemicals being 56-81% lower, on average, than the unlaundered hoods. PBDEs, on average, were 43% higher in the laundered hoods, most likely from cross contamination. After this initial testing, four of the five unlaundered exposed hoods were subsequently laundered with other heavily exposed (unlaundered) and unexposed (new) hoods. Post-laundering evaluation of these hoods revealed increased levels of PBDEs, NPBFRs, and OPFRs in both previously exposed and unexposed hoods, indicating cross contamination. For PAHs, there was little evidence of cross contamination and the exposed hoods were significantly less contaminated after laundering (76% reduction; p = 0.011). Further research is needed to understand how residual contamination on hoods could contribute to firefighters' systemic exposures.

Potential human exposure to halogenated flame-retardants in elevated surface dust and floor dust in an academic environment.

Most households and workplaces all over the world possess furnishings and electronics, all of which contain potentially toxic flame retardant chemicals to prevent fire hazards. Indoor dust is a recognized repository of these types of chemicals including polybrominated diphenyl ethers (PBDEs) and non-polybrominated diphenyl ethers (non-PBDEs). However, no previous U.S. studies have differentiated concentrations from elevated surface dust (ESD) and floor dust (FD) within and across microenvironments. We address this information gap by measuring twenty-two flame-retardant chemicals in dust on elevated surfaces (ESD; n=10) and floors (FD; n=10) from rooms on a California campus that contain various concentrations of electronic products. We hypothesized a difference in chemical concentrations in ESD and FD. Secondarily, we examined whether or not this difference persisted: (a) across the studied microenvironments and (b) in rooms with various concentrations of electronics. A Wilcoxon signed-rank test demonstrated that the ESD was statistically significantly higher than FD for BDE-47 (p=0.01), BDE-99 (p=0.01), BDE-100 (p=0.01), BDE-153 (p=0.02), BDE-154 (p=0.02), and 3 non-PBDEs including EH-TBB (p=0.02), BEH-TEBP (p=0.05), and TDCIPP (p=0.03). These results suggest different levels and kinds of exposures to flame-retardant chemicals for individuals spending time in the sampled locations depending on the position of accumulated dust. Therefore, further research is needed to estimate human exposure to flame retardant chemicals based on how much time and where in the room individuals spend their time. Such sub-location estimates will likely differ from assessments that assume continuous unidimensional exposure, with implications for improved understanding of potential health impacts of flame retardant chemicals.

Flame retardant transfers from U.S. households (dust and laundry wastewater) to the aquatic environment.

Levels of flame retardants in house dust and a transport pathway from homes to the outdoor environment were investigated in communities near the Columbia River in Washington state (WA). Residential house dust and laundry wastewater were collected from 20 homes in Vancouver and Longview, WA and analyzed for a suite of flame retardants to test the hypothesis that dust collecting on clothing and transferring to laundry water is a source of flame retardants to wastewater treatment plants (WWTPs) and subsequently to waterways. Influent and effluent from two WWTPs servicing these communities were also analyzed for flame retardants. A total of 21 compounds were detected in house dust, including polybrominated diphenyl ethers (PBDEs), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB or EH-TBB), bis(2-ethylhexyl) 3,4,5,6-tetrabromophthalate (TBPH), 1,2-bis(2,4,6,-tribromophenoxy)ethane (BTBPE) and decabromodiphenylethane (DBDPE), hexabromocyclododecane (HBCD or HBCDD), tetrabromobisphenol A (TBBPA), and three chlorinated organophosphate flame retardants (ClOPFRs), tris(1,3-dichloro-2-propyl)phosphate (TDCPP or TDCIPP), tris(1-chloro-2-propyl)phosphate (TCPP or TCIPP), and tris(2-chloroethyl)phosphate (TCEP). Levels ranged from 3.6 to 82,700 ng g(-1) (dry weight). Of the 21 compounds detected in dust, 18 were also detected in laundry wastewater. Levels ranged from 47.1 to 561,000 ng L(-1). ClOPFRs were present at the highest concentrations in both dust and laundry wastewater, making up 72% of total flame retardant mass in dust and 92% in laundry wastewater. Comparison of flame retardant levels in WWTP influents to estimates based on laundry wastewater levels indicated that laundry wastewater may be the primary source to these WWTPs. Mass loadings to the Columbia River from each treatment plant were by far the highest for the ClOPFRs and ranged up to 114 kg/yr for TCPP.

Polybrominated diphenyl ether accumulation in an agricultural soil ecosystem receiving wastewater sludge amendments.

Few studies have addressed bioaccumulation of organic pollutants associated with land-application of biosolids. We thus examined PBDE burdens within a soil ecosystem receiving long-term sludge amendments and a reference soil ecosystem receiving only manure inputs. No PBDEs were detected in reference site samples, but sludge-amended soils contained 17 600 ± 2330 µg/kg ∑3-7PBDE (total organic carbon (TOC) basis). ∑3-7PBDE burdens were highest in soil invertebrates with the greatest contact with sludge-amended soil (e.g., ∑3-7PBDE of 10 300 ± 2670 and 3000 ± 200 µg/kg lipid for earthworms and detritivorous woodlice, respectively). PBDEs were below quantitation limits in vegetation from the sludge-amended site. Surprisingly, we measured quantifiable PBDE burdens in only a single sample of predaceous ground spiders from the sludge-amended site. BDE-209 burdens in sludge-amended soil and earthworms were 7500 ± 2800 µg/kg TOC and 6500 ± 4100 µg/kg lipid, respectively. BDE 209 was detected in fewer taxa, but the burden in a detritivorous millipede composite was high (86 000 µg/kg lipid). PBDE congener patterns differed among species, with worms and ground beetles exhibiting Penta-BDE-like patterns. Penta-BDE biota-soil accumulation factors (BSAFs) ranged from 0.006 to 1.2, while BDE-209 BSAFs ranged from 0.07 to 10.5. δ(13)C and δ(15)N isotope signatures were poorly correlated with PBDE burdens, but sludge-amended samples were significantly δ(15)N enriched.

Twenty years later: PBDEs in fish from U.S. sites with historically extreme contamination.

Shortly after their production ban PBDE environmental levels retreated from their peak (circa 2000), but rates of decrease appear to be slowing. Therefore, to update environmental PBDE trends, this study re-examined a U.S. riverine system found in 1999 to have the highest PBDE fish tissue (fillet) burdens in the world. Archived 2018-2020 fish tissues were analyzed for PBDEs and results compared to 1999-2000 and 2007 levels. On a positive note, levels decreased by >75% over 20 years. However, PBDEs were still detectable at each collection site (n = 16) and in 93% of the samples. The highest PBDE level (16,300 ng g-1 lipid weight) was observed in fish from the Dan R., downstream from the Hyco R. (where the world's highest level was previously reported). Levels within Hyco R. fish have declined at an annual rate of 30% through 2007. However, reductions during the subsequent 12 years have diminished to only 1.2%. Fillet levels since 2007 actually increased at an estimated annual rate of 8% immediately downstream from the Hyco R. Congener profiles varied between species, likely due to hepatic enzyme debromination, indicating single congener-based health risk evaluations may not be sufficiently protective. Within North America, PBDE fish levels in this freshwater system were twice those of North America's Great Lakes and exceeded by 10-fold those in carp examined from Illinois, USA., another historical hotspot. Average fish PBDE levels also exceed maxima observed in European and Asian riverine systems and were 1000's of times higher than the environmental quality standard (EQS) set by European Parliament (0.0085 ng g-1 wet weight, aquatic biota). Therefore, to protect human health and the environment, PBDE monitoring should remain a priority for regulatory agencies with the goal to identify and eliminate their source and to consider their potential health impacts in the context of other co-existing (emerging and legacy) contaminants.

Brominated flame-retardants in Sub-Saharan Africa: burdens in inland and coastal sediments in the eThekwini metropolitan municipality, South Africa.

Brominated flame-retardant (BFR) additives are present in many polymeric consumer products at percent levels. High environmental concentrations have been observed near cities and polymer, textile, and electronics manufacturing centers. Most studies have focused on European, North American, and Asian locales. Releases are likely rising most dramatically in countries with weak environmental and human health regulation and enforcement, demand for electrical and electronic equipment (EEE) is escalating, and importation of waste EEE occurs. Several African countries meet these criteria, but little data are available on burdens or sources. To better understand the extent of BFR environmental dissemination in a southern African urban community, inland and coastal sediments were collected in the eThekwini metropolitan municipality, South Africa, and analyzed for polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (TBB), 2-ethylhexyl 2,3,4,5-tretabromophalate (TBPH), 1,2-bis (2,4,6-tribromophenoxy) ethane (BTBPE), and decabromodiphenyl ethane (DBDPE). BFRs were detected in all samples (n = 45). Concentration data are presented on total organic carbon (TOC) normalized basis. ΣBFR ranged from 114 to 47 100 ng g(-1). Decabromodiphenyl ether was detected in 93% of samples (mean concentration 3208 ng g(-1)) followed by TBB at 91% (mean conc. 545 ng g(-1)). Durban Bay is strongly influenced by urban runoff and tidal hydrology, and sediments therein exhibited ΣPBDE concentrations ranging from 1850 to 25 400 ng g(-1) (median conc. 3240 ng g(-1)). These levels rival those in the heavily impacted Pearl River Delta, China. BFRs likely enter the South African environment during manufacture of BFR-containing products, during and following product use (i.e., after disposal and as a result of materials recycling activities), and from nonpoint sources such as atmospheric fallout and urban runoff. These results underline the need to investigate further the environmental burdens and risks associated with BFRs in developing countries.

In situ accumulation of HBCD, PBDEs, and several alternative flame-retardants in the bivalve (Corbicula fluminea) and gastropod (Elimia proxima).

Alternative brominated flame-retardants (BFRs), 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (TBB), 2-ethylhexyl 2,3,4,5-tetrabromophthalate (TBPH), 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE) and decabromodiphenyl ethane (DBDPE), are now being detected in the environment. However, contaminant bioavailability is influenced by the organisms' ecology (i.e., route of uptake) and in situ environmental factors. We observed that the filter-feeding bivalve (Corbicula fluminea) and grazing gastropod (Elimia proxima), collected downstream from a textile manufacturing outfall, exhibited TBB, TBPH, and BTBPE concentrations from 152 to 2230 ng g(-1) lipid weight (lw). These species also contained additional BFRs. Maximum levels of total hexabromocyclododecane diastereomers (∑HBCDs) in these species were 363,000 and 151,000 ng g(-1) lw, and those of polybrominated diphenyl ethers (∑PBDEs) were 64,900 and 47,200 ng g(-1) lw, respectively. These concentrations are among the highest reported to date worldwide. While BDE-209 was once thought to be nonbioavailable and resistant to degradation, it was the dominant BFR present and likely debromination products were detected. Contributions of α- and ß-HBCD were higher in tissues than sediments, consistent with γ-HBCD bioisomerization. Mollusk bioaccumulation factors were similar between HBCD and PBDEs with 4 to 6 bromines, but factors for TBB, TBPH, and BTBPE were lower. Despite different feeding strategies, the bivalves and gastropods exhibited similar BFR water and sediment accumulation factors.

Polybrominated diphenyl ethers in U.S. sewage sludges and biosolids: temporal and geographical trends and uptake by corn following land application.

Polybrominated diphenyl ethers (PBDEs) have been used extensively to flame-retard polymers and textiles. These persistent chemicals enter wastewater streams following manufacture, use, and disposal, concentrating in the settled solids during treatment. Land application of stabilized sewage sludge (known as biosolids) can contribute PBDEs to terrestrial systems. Monitoring sludge/biosolids contaminant burdens may be valuable in revealing trends in societal chemical usage and environmental release. In archived Chicago area sludges/biosolids from 1975 to 2008, penta-BDE concentrations increased and then plateaued after about 2000. Penta-BDE manufacture in the United States ended in December 2004. Deca-BDE concentrations in biosolids rose from 1995 to 2008, doubling on a 5-year interval. Evaluation of U.S. Environmental Protection Agency Targeted National Sewage Sludge Survey data from 2006 to 2007 revealed highest penta-BDE biosolids levels from western and lowest from northeastern wastewater treatment plants (2120 and 1530 µg/kg, respectively), consistent with patterns reported in some recent indoor dust and human blood studies. No significant regional trends were observed for deca-BDE concentrations. Congener patterns in contemporary Chicago biosolids support the contention that BDE-209 can be dehalogenated to less brominated congeners. Biosolids application on agricultural fields increased PBDE soil concentrations. However, corn grown thereon did not exhibit measurable PBDE uptake; perhaps due to low bioavailability of the biosolids-associated flame retardants.

Do temporal and geographical patterns of HBCD and PBDE flame retardants in U.S. fish reflect evolving industrial usage?

Polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD) are common flame retardants in polymers and textiles. Recognition of the persistent, bioaccumulative, and toxic properties of PBDEs has prompted reductions in their use. In contrast, HBCD has received less scrutiny. The U.S has historically been a dominant BFR consumer. However, the few publications on HBCD in wildlife here suggest modest levels compared to Asian and European studies. In contrast, the HBCD concentrations we detected in U.S. fish are among the highest reported in the world. The temporal trends observed suggest that HBCD use may have risen, and that of Penta-BDE declined, following the 2004 termination of its U.S. manufacture. For example, Hyco River carp collected in 1999-2002 exhibited a mean ∑HBCD (sum of α-, ß- and γ-HBCD) concentration of only 13 ng/g (lipid weight basis), but was 4640 ng/g in fish collected in 2006-2007. In contrast, the mean ∑PBDE level in these same fish decreased from 40,700 ng/g in 1999-2002 to 9140 ng/g in 2006-2007. Concentrations of HBCD and PBDEs in several Hyco River fish species exceeded those from rivers less influenced by manufacturing outfalls. Results support the contention that textile-related production, relative to its BFR market share, may release disproportionately large amounts of HBCD to the environment.

Assessment of triphenyl phosphate (TPhP) exposure to nail salon workers by air, hand wipe, and urine analysis.

Triphenyl phosphate (TPP or TPhP) is commonly used as an additive plasticizer or organophosphate flame retardant (OPFR) in consumer products including nail polish. We evaluated exposure to TPhP from 12 nail salon technicians working at four nail salons located in California over a period of two work days. Bulk samples of 15 nail polishes and other nail products were collected. Study participants also provided two personal air samples, two hand wipe samples (pre- and post-shift on day two), and two urine samples (pre-shift day one and post-shift day two). The geometric mean (GM) of TPhP air sampling concentrations was 7.39 ng/m3. Post-shift TPhP hand wipe concentrations (GM 1.35 µg/sample) were significantly higher (p = 0.024) than pre-shift hand wipe concentrations (GM 0.29 µg/sample). Diphenyl phosphate (DPP or DPhP), a urinary metabolite of TPhP used in this study as a biomarker of exposure, was detected in all post-shift urine samples and 75% of urine pre-shift samples. DPhP post-shift concentrations (GM 1.35 µg/g creatinine) were significantly higher than pre-shift concentrations (GM 0.84 µg/g creatinine; p = 0.012). In addition, DPhP post-shift concentrations were correlated with TPhP post-shift hand wipe concentrations, suggesting dermal contact may be a relevant exposure pathway for nail salon workers.

A noninvasive environmental monitoring tool for brominated flame-retardants (BFRs) assisted by conservation detection dogs.

Fecal matter is a useful noninvasive/nondestructive media for evaluating contaminants in wildlife, as residues therein have been observed to correlate with body burdens. Conservation detection dog-handler teams can be used to optimize the acquisition of fecal samples. To build on previous work, sentinel-species' (i.e. mink (Mustela vison) and otter (Lontra canadensis)) fecal matter was opportunistically located by a detection dog team along the tri-river system of Missoula, Montana, USA. Sediments were also collected. Samples were used to develop an analytical method from fecal matter to determine habitat exposure to the brominated flame-retardants (BFRs): polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCDD), 2-ethylhexyl 2, 3, 4, 5-tetrabromobenzoate (EH-TBB), di (2-ethylhexyl)-2, 3, 4, 5-tetrabromophthalate (BEH-TEBP) and decabromodiphenyl ethane (DBDPE). Sediments contained PBDEs (BDE-99 and BDE-209) and EH-TBB at detection rates of 67%, 33% and 67%, respectively. BDE-99, -209 and EH-TBB were also detected in mink and otter feces, at rates of 81%, 25% and 81%, respectively; plus BEH-TEBP at 13%. BFR levels correlated positively with human population density except along the lower Bitterroot River, where BDE-209 sediment and feces levels exceeded other sites by several orders of magnitude. Fecal matter body burden estimates indicated marginal PBDE exposure. However, exposure to their replacements, EH-TBB and BEH-TEBP, were at levels that may adversely affect healthy Mustelidae populations. Proof-of-concept was achieved; validation results were within established standards for the development of analytical methods. The established application of conservation dog-handler teams to facilitate the collection of fecal matter for BFR analysis represents a valuable, but currently underutilized environmental monitoring tool.

Worker exposure to flame retardants in manufacturing, construction and service industries.

Workers in several industries are occupationally exposed to flame retardants. This study characterizes flame retardant exposure for nine industries through air and hand wipe measures for 105 workers. Specifically, we analyzed 24 analytes from three chemical classes: organophosphate flame retardants (OFRs), polybrominated diphenyl ethers (PBDEs), and non-PBDE brominated flame retardants (NPBFRs). The industries were: carpet installation, chemical manufacturing, foam manufacturing, electronic scrap, gymnastics, rigid board installation, nail salons, roofing, and spray polyurethane foam. Workers wore personal air samplers for two entire workdays and provided hand wipe samples before and after the second work day. Bulk products were also analyzed. The air, hand wipe and bulk samples were evaluated for relevant flame retardants. Spray polyurethane foam workers' tris(1-chloro-2-propyl) phosphate air (geometric mean = 48,500 ng/m3) and hand wipe (geometric mean = 83,500 ng per sample) concentrations had the highest mean industry concentration of any flame retardant analyzed in this study, followed by triphenyl phosphate air concentration and tris(1,3-dichloro-2-propyl) phosphate hand wipe concentration from chemical manufacturers. Overall, OFR air and hand wipe concentrations were higher and more prevalent than PBDEs or non-PBDE brominated flame retardants. Some industries including spray polyurethane foam application, chemical manufacturing, foam manufacturing, nail salons, roofing, and rigid polyiso board installation had high potential for both air and hand exposure to OFRs. Carpet installers, electronic scrap workers, and gymnastic workers had exposures to all three classes of flame retardants including PBDEs, which were phased out of production in 2013. Air and dermal exposures to OFRs are prevalent in many industries and are replacing PBDEs in some industries.

Concentrations and loadings of organophosphate and replacement brominated flame retardants in house dust from the home study during the PBDE phase-out.

Polybrominated diphenyl ethers, a class of flame retardants and endocrine disruptors, have been substituted in new products by organophosphate (OPFR) and replacement brominated flame retardants (RBFR). OPFRs and RBFRs readily migrate from consumer products into dust where humans are exposed via incidental ingestion and inhalation. We quantified concentrations and loadings of OPFRs and RBFRs in house dust samples (n = 317) collected from the homes of Cincinnati women between 2003 and 2006 and examined their associations with demographic and house characteristics. Tris-(1-chloro-2-propyl)-phosphate (TCIPP, geometric mean [GM]: 2140 ng g-1, range: 70.1-166,000 ng g-1), tris-(1,3-dichloro-2-propyl)-phosphate (TDCIPP, GM: 1840 ng g-1, range: 55.2-228,000 ng g-1), triphenyl phosphate (TPHP, GM: 1070 ng g-1, range: 34.1-62,100 ng g-1), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB, GM: 59.5 ng g-1, range: 2.82-7800 ng g-1), and bis-(2-ethylhexyl)-tetrabromophthalate (BEH-TEBP, GM: 121 ng g-1, range 2.17-13,600 ng g-1) were all detected in >90% of dust samples; tris-(2-chloroethyl)-phosphate (TCEP, GM: 669 ng g-1, range: 56.8-160,000 ng g-1) was detected in 80.1% of samples. Concentrations of EH-TBB and BEH-TEBP increased in house dust from 2003 to 2006. The number of people living in the home, race, education, floor type, and year of sample collection were associated with some OPFR and RBFR concentrations and loadings. This study suggests that OPFRs and RBFRs were ubiquitous in house dust during the PBDE phase-out and justifies more research on the consequences of exposure to these environmental chemicals.

Polybrominated diphenyl ether flame retardants in Chesapeake Bay region, U.S.A., peregrine falcon (Falco peregrinus) eggs: urban/rural trends.

A total of 23 peregrine falcon (Falco peregrinus) eggs were obtained between 1993 and 2002 from 13 nests, encompassing 11 locations in the Chesapeake Bay region, U.S.A. When multiple eggs were available from the same clutch, average clutch contaminant concentrations were calculated. An overall median total polybrominated diphenyl ether (PBDE) level of 201 ng/g wet weight was determined for the eggs/clutches examined. The maximum in an individual egg, from an urban highway bridge site, was 354 ng/g. This egg also exhibited the highest BDE 209 burden (48.2 ng/g). Compared to distributions reported in fish and piscivorous birds, falcon eggs were enriched in the more brominated congeners. The BDE congeners 153, 99, and 100 constituted 26.0, 24.8, and 13.1%, respectively, of total PBDEs. In most aquatic species, BDE 47 is the most abundant congener reported; however, it constituted only 4.4% of total PBDEs in the eggs of the present study. The median BDE 209 concentration was 6.3 ng/g. The sum of the octa- to nonabrominated congeners (BDEs 196, 197, 206, 207, and 208) contributed, on average, 14.0% of total PBDEs, exceeding the contribution of BDE 209 (5.9%). Concentrations of polychlorinated biphenyls (PCBs) and 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (4,4'-DDE) also were determined in a subset of 16 eggs (collected in 2001-2002 from six nests) and were an order of magnitude greater than the corresponding PBDEs. Median BDE 209 concentrations were significantly correlated (p < 0.01, Spearman R = 0.690) with the human population density of the area surrounding the nest. Total PBDEs, total PCBs, and 4,4'-DDE levels were not correlated to human population density.

Field evaluation of sequential hand wipes for flame retardant exposure in an electronics recycling facility.

Flame retardants have been associated with endocrine disorders, thyroid disruption, reproductive toxicity, and immunological interference. Through dismantling and recycling electronics and electric products, flame retardants can be released into the air and settle on work surfaces which may lead to dermal exposure. Hand wipe sampling is commonly used to evaluate dermal exposure. This study assesses the removal efficiency of wipes on the hands of recycling employees, and to compare the efficacy of two common surface wipe sampling materials. We used three sequential hand wipes and quantified the percentage of flame retardants that was removed by each hand wipe in the sequence. Two common wipe materials (gauze and twill) were used to compare the ability to remove flame retardants. The wipes were collected from 12 employees at a U.S. electronics recycling facility immediately at the end of their shift, prior to washing their hands. Results show that although the first wipe removed the highest median percent of the sum of the three wipes for most flame retardants, there was a wide range of the percentages of total individual flame retardants removed by both gauze (4%-98%) or twill hand wipe (1%-89%). Approximately half of the flame retardants a high percentage (>50%) removed by the second and third wipes. This suggests that a single wipe is not sufficient to characterize the extent of dermal contamination. The average of the total amount of flame retardants removed by twill wipes was greater than the average using gauze, but the difference was not statistically significant.

Brominated and organophosphate flame retardants along a sediment transect encompassing the Guiyu, China e-waste recycling zone.

e-Waste recycling using crude techniques releases a complex, yet incompletely characterized mixture of hazardous materials, including flame retardants (FRs), to the environment. Their migration downstream and the associated risks also remain undocumented. We examined 26 FRs (18 brominated (BFRs: 12 polybrominated diphenyl ether (PBDE) congeners, plus 6 alternatives) and 8 organophosphate esters (OPEs)) in surficial sediments of the Lian River. Sampling encompassed the river's origin, through the Guiyu e-waste recycling zone, to its mouth, as well as associated tributaries. OPE exceeded BFR concentrations in most sediments, despite their far greater water solubilities. Among OPEs, tris(1-chloro-2-propyl) phosphate dominated upstream, but shifted to triphenyl phosphate in Guiyu and downstream sediments. For PBDEs, Deca-BDE dominated upstream, but Penta-BDE prevailed in Guiyu and at many downstream sites. Among emerging alternative BFRs, decabromodiphenyl ethane dominated upstream, transitioning to 1,2-bis(2,4,6,-tribromophenoxy)ethane in Guiyu sediments. Penta-BDE (BDE-47 + -99, 668-204,000 ng g-1, ∑PBDEs 2280-287,000 ng g-1), tetrabromobisphenol A (2,720-41,200 ng g-1), 1,2-bis(2,4,6,-tribromophenoxy)ethane (222-9870 ng g-1) and triphenyl phosphate (4260-1,710,000 ng g-1, OPEs 6010-2,120,000 ng g-1) concentrations in Guiyu sediments were among the highest reported in the world to date. The continuing dominance of these e-waste indicative FRs in sediments downstream of Guiyu suggested that FR migration from Guiyu occurred. Hazard quotients >1.0 indicated that the extreme sediment concentrations of individual FRs posed ecological risks in most Guiyu reach and downstream areas. Simultaneous exposure to multiple FRs likely increased risks. However, risks may be mediated if FRs were associated with strong sorbents, e.g. carbon black from burned debris, hydrophobic polymer fragments, or resided as additives within polymer fragments.

Occupational exposure to polybrominated diphenyl ethers (PBDEs) and other flame retardant foam additives at gymnastics studios: Before, during and after the replacement of pit foam with PBDE-free foams.

Coaches spend long hours training gymnasts of all ages aided by polyurethane foam used in loose blocks, mats, and other padded equipment. Polyurethane foam can contain flame retardant additives such as polybrominated diphenyl ethers (PBDEs), to delay the spread of fires. However, flame retardants have been associated with endocrine disruption and carcinogenicity. The National Institute for Occupational Safety and Health (NIOSH) evaluated employee exposure to flame retardants in four gymnastics studios utilized by recreational and competitive gymnasts. We evaluated flame retardant exposure at the gymnastics studios before, during, and after the replacement of foam blocks used in safety pits with foam blocks certified not to contain several flame retardants, including PBDEs. We collected hand wipes on coaches to measure levels of flame retardants on skin before and after their work shift. We measured flame retardant levels in the dust on window glass in the gymnastics areas and office areas, and in the old and new foam blocks used throughout the gymnastics studios. We found statistically higher levels of 9 out of 13 flame retardants on employees' hands after work than before, and this difference was reduced after the foam replacement. Windows in the gymnastics areas had higher levels of 3 of the 13 flame retardants than windows outside the gymnastics areas, suggesting that dust and vapor containing flame retardants became airborne. Mats and other padded equipment contained levels of bromine consistent with the amount of brominated flame retardants in foam samples analyzed in the laboratory. New blocks did not contain PBDEs, but did contain the flame retardants 2-ethylhexyl 2,3,4,5-tetrabromobenzoate and 2-ethylhexyl 2,3,4,5-tetrabromophthalate. We conclude that replacing the pit foam blocks eliminated a source of PBDEs, but not 2-ethylhexyl 2,3,4,5-tetrabromobenzoate and 2-ethylhexyl 2,3,4,5-tetrabromophthalate. We recommend ways to further minimize employee exposure to flame retardants at work and acknowledge the challenges consumers have identifying chemical contents of new products.