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Brominated and phosphorus-based flame retardants (PFRs) were measured in foam and fabric samples from 18 newly marketed children’s car seats. The concentrations of two cyclic phosphonates {PMMMPs, 5-ethyl-2-methyl-2-oxido-1,3,2-dioxaphosphinan-5-yl)methyl methyl methylphosphonate and bis[(5-ethyl-2-methyl-1,3,2-dioxaphosphorinan-5-yl)methyl] methyl phosphonate p,p′-dioxide} were quantitatively measured for the first time in the North American environment and were much higher than those of other flame retardants. Median PMMMP concentrations were 73.6 μg/g, accounting on average for 52% of the total FR concentrations, indicating an intentional addition of PMMMPs during the manufacturing process of these car seats. Two other emerging PFRs [tris(2,4-di-Hi Katie,t-butylphenyl) phosphate (TDTBPP) and resorcinol bis(diphenyl phosphate) (RDP)] were detected for the first time in baby products at median levels of 1.11 and 6.15 μg/g, respectively. Other frequently detected PFRs included triethyl phosphate (TEP), tr...

Fabric and foam samples from popular children car seats marketed in the United States during 2018 were tested for fluorine content by particle-included gamma ray emission spectroscopy (PIGE, n = 93) and X-ray photoelectron spectroscopy (XPS, n = 36), as well as for per- and polyfluoroalkyl substances (PFAS) by liquid and gas chromatography mass spectrometry (LC/MS and GC/MS, n = 36). PFAS were detected in 97% of the car seat samples analyzed with MS, with total concentrations of 43 PFAS (∑PFAS) up to 268 ng/g. Fabric samples generally had greater ∑PFAS levels than foam and laminated composites of foam and fabric. The three fabric samples with the highest total fluorine content as represented by the highest PIGE signal were also subjected to ultraviolet (UV) irradiation and the total oxidizable precursor (TOP) assay. Results from these treatments, as well as the much higher organofluorine levels measured by PIGE compared to LC/MS and GC/MS, suggested the presence of side-chain fluorotelomer-based polymers (FTPs), which have the potential to readily degrade into perfluoroalkyl acids (PFAAs) under UV light. Furthermore, fluorotelomer (meth)acrylates were found to be indicators for the presence of (meth)acrylate-linked FTPs in consumer products, and thus confirmed that at least half of the tested car seats had FTP-treated fabrics. Finally, extraction of selected samples with synthetic sweat showed that ionic PFAS, particularly those with fluorinated carbons ≤8, can migrate from fabric to sweat, suggesting a potential dermal route of exposure.

Hazardous chemicals used in electronic and electrical consumer products can re-enter commerce when these products are recycled. The objectives of this study were to 1) identify the possible sources of unexpected chemicals and elements in consumer products, including the use of recycled E-waste plastics and 2) demonstrate bromine detection with nondestructive spectroscopy as an indicator of brominated flame retardants contaminating new products via recycled waste streams. More than 1500 consumer products of diverse types purchased in 2012-2014 were examined using X-ray fluorescence spectroscopy for correlations between bromine and other elements. New electronic products were much more likely than new non-electronics to contain greater than 1000 ppm bromine, consistent with intentionally added flame retardants, while non- electronic products were more likely to contain between 5 and 100 ppm bromine, suggesting unintentional contamination. A typical suite of elements present in E-waste was found in a majority of plastic products. Two product categories, vinyl floor tiles and beaded necklaces/garlands, were explored in more detail. Specific flame retardant chemicals in bead samples were identified by mass spectrometry and their distribution in beads was studied using scanning electron microscopy and energy dispersive spectroscopy. Five brominated chemicals typically used as flame retardants, including BDE-209, were identified in 50 of 50 Mardi Gras beads analyzed.

There is growing evidence that small-scale, coastal, passive net fisheries may be the largest single threat to some sea turtle populations. We review assessments of turtle interactions in these fisheries, and experiments on gear-technology approaches (modifying gear designs, materials and fishing methods) to mitigate turtle by-catch, available from a small number of studies and fisheries. Additional assessments are needed to improve the limited understanding of the relative degree of risk coastal net fisheries pose to turtle populations, to prioritize limited conservation resources and identify suitable mitigation opportunities. Whether gear technology provides effective and commercially viable solutions, alone or in combination with other approaches, is not well-understood. Fishery-specific assessments and trials are needed, as differences between fisheries, including in gear designs; turtle and target species, sizes and abundance; socioeconomiccontext; andpracticality affectefficacyandsuitabilityofbycatch mitigation methods. Promising gear-technology approaches for gillnets and trammelnetsinclude:increasinggearvisibilitytoturtlesbutnottargetspecies,through illuminationandlinematerials;reducingnetverticalheight;increasingtiedownlength or eliminating tiedowns; incorporating shark-shaped silhouettes; and modifying float characteristics, the number of floats or eliminating floats. Promising gear-technology approachesforpoundnetsandothertrapgearinclude:replacingmeshwithropesinthe upperportionofleaders;incorporatingaturtlereleasingdeviceintotraps;modifyingthe shape of the trap roof to direct turtles towards the location of an escapement device; usinganopentrap;andincorporatingadevicetopreventseaturtleentranceintotraps.

Applying a hockey stick parametric dose-response model to data on late or retarded development in Iraqi children exposed in utero to methylmercury, with mercury (Hg) exposure characterized by the peak Hg concentration in mothers' hair during pregnancy, Cox et al. calculated the "best statistical estimate" of the threshold for health effects as 10 ppm Hg in hair with a 95% range of uncertainty of between 0 and 13.6 ppm. A new application of the hockey stick model to the Iraqi data shows, however, that the statistical upper limit of the threshold based on the hockey stick model could be as high as 255 ppm. Furthermore, the maximum likelihood estimate of the threshold using a different parametric model is virtually zero. These and other analyses demonstrate that threshold estimates based on parametric models exhibit high statistical variability and model dependency, and are highly sensitive to the precise definition of an abnormal response. Consequently, they are not a reliable basis for setting a reference dose (RfD) for methylmercury. Benchmark analyses and statistical analyses useful for deriving NOAELs are also presented. We believe these latter analyses--particularly the benchmark analyses--generally form a sounder basis for determining RfDs than the type of hockey stick analysis presented by Cox et al. However, the acute nature of the exposures, as well as other limitations in the Iraqi data suggest that other data may be more appropriate for determining acceptable human exposures to methylmercury.

The presence and potential health effects of toxic chemicals found in vehicle interiors are receiving increasing attention. For example, recent Greek studies of active cabin air samples in 2006/08 models have revealed high concentrations of lower brominated flame retardants (BFRs) that were banned in 2005. Our investigation of 11 interior vehicle components of over 400 domestic and imported 2006-2008 models using Xray Fluorescence Spectroscopy (XRF) reveals widespread use of (BFRs), PVC, and selected heavy metals. In addition to these data we present results on the formation of lower brominated flame retardants via photodegradation of deca-bromodiphenylether (decaBDE) facilitated by solar radiation and elevated temperatures comparable to those in vehicles. Experiments using sealed quartz ampoules containing deca-BDE in nonane show complete photo-chemical degradation of deca-BDE after exposure to sunlight for 97.6 hours under environmental conditions representative of vehicle interiors. Degradation products include tetra, penta, hexa, hepta, octa, and some nonaBDEs. Bromine mass balances in terms of PBDEs found after exposure range between 37% for longest and 85 % for intermediate exposures, respectively. The unaccounted bromine in mass balances indicate formation of sofar unknown reaction products. Exposure of passengers to toxic degradation products of decaBDE is an important health concern and the phase-out of BFR use in automobiles is recommended. INTRODUCTION Polybrominated diphenyl ethers (PBDEs) are composed of two rings (phenyl rings) linked by an oxygen bridge (ether linkage). There are up to ten locations where a bromine atom can attach to a carbon on the rings. If a PBDE has ten bromines, it’s called a deca-BDE; five bromines is a penta-BDE. After the recent ban of the toxic commercial products penta-BDE and octa-BDE, decabromodiphenylether (BDE-209 or deca-BDE) has become the most widely used additive commercial brominated flame retardant. Deca-BDE and other BFRs are primarily used in textiles, carpet backings, foams, and to a smaller extent in electronic circuit boards and plastics (1). As much as 250 grams of PBDEs are reportedly used in vehicles (1). Because of its widespread commercial usage, BDE-209 is now a major contaminant in the indoor and outdoor environment (35). PBDEs including BDE-209 are found in window films (2), sewage sludge (3), the human food chain (4, 5) and other biological media. High levels of deca-BDE have been reported in vehicle dust (6, 36), and more recently in house dust (7, 8, 9), and dryer lint (10). Dust in particular may provide a major pathway for particle inhalation and ingestion, particularly for toddlers. Evaporative releases and emission rates of deca and lower brominated congeners have been measured (11, 12) from an ABS television case at 23 0C suggesting that vapor inhalation may provide an additional pathway of absorption by mammals. Decomposition of BDE-209 into more toxic lower brominated BDEs, dioxins, and furans is of high concern to public and environmental health. See “Previous Photo-Chemical Degradation Studies of BDE-209” in this paper for further discussion of this issue. In her recent *9-2009-01-1301* Licensed to University of Michigan Licensed from the SAE Digital Library Copyright 2009 SAE International E-mailing, copying and internet posting are prohibited Downloaded Monday, May 11, 2009 10:19:38 AM Author:Gilligan-SID:1178-GUID:19191521-141.213.32.150 review, Stapleton (13) demonstrated multiple pathways for the degradation of deca-BDE in the environment including microbial, reductive, and photochemical mechanisms. The formation of toxic degradation products was apparently the primary reason for the proposal of a deca-BDE ban by some European countries, such as Norway, Sweden and Denmark (14). Most recently, the environment ministry of Norway has announced (26) an all-but-total ban on new products containing the brominated flame retardant deca-BDE in effect from April 1, 2008. However, the transportation sector received the only exception to this ban (14). This is unfortunate since the outgassing of deca-BDE from sun-exposed vehicles is far higher than from furniture or electronics housed at ambient temperatures. THE USE AND FATE OF BFR(S) IN VEHICLES Since adults in the U.S. spend on average about 100 minutes per day in vehicles (29), an assessment of the chemical contents and environmental conditions of vehicle interiors is paramount to determining the risk of potential health effects and relevant exposure pathways. In an earlier study (1, 2) the authors reported the presence of BDE-209 and lower brominated BDEs in vehicle dust. However, windshield films showed no measureable levels of the deca congener. Because of the unique physical conditions of sun-exposed cars (temperature up to 700C; and UV radiation), photodegradation of BDE-209 and possibly other brominated flame-retardants (BFRs) was expected but not experimentally verified. Since the 2005 ban of commercial uses of pentaand octa-BDEs, it is assumed that these more toxic chemicals will be absent and replaced by BDE-209 or other BFRs in 2006/2008 car models. However, this assumption is questionable in light of a recent study (28) of 2006/07 models revealing high concentrations of tetraand penta-BDEs in the air of these vehicles. While photodegradation of deca-BDE cannot be ruled out in this study, the ratios of BDE47/BDE-99 closely resembled that of commercial pentaformulations in 50% of these new vehicles. Use of preban stock of materials by suppliers may account for these findings. In a preliminary survey we established the presence and extent of BFR usage by direct testing 11 interior vehicle components in over 400 new 2006/7/8/9 models (15) using a non-destructive X-ray fluorescent technology (Model Alpha XRF, Innov-X Systems, Inc., Woburn, MA). This analysis measures bromine content without specifying individual chemical structures (16). The use of non-destructive XRF analysis is now more widely preferred over costly and time-consuming analytical methods (22, 23). The reliability of the XRF (RoHS) method with homogeneous materials has been studied (23) for several elements and shows satisfactory correlation with traditional analytical methods (GC/MS) for bromine and other elements. XRF-measured bromine levels in foam and plastic samples have been highly correlated with GC/MS measured bromine by Li (31) (r: 0.99); Allen (32) (r: 0.93); and XRF measured bromine was an excellent predictor of PBDE content in Allen (32) (r: 0.99). Data showing bromine contents of >1,000 ppm were considered as signifying the presence of BFRs, most likely BDE-209. Vehicles were sampled at ambient temperature with engine and all accessories off. The data presented in Table 1, 2, and 3 reveal no BFR-uses in all components by some manufacturers but not by others. This clearly shows that flame protection without the use of BFRs is available for all vehicle components. In addition to bromine, we tested and published (15) data on chlorine (PVC), lead and other heavy metals. The trend of BFR use by manufacturer is shown in Table 4 and BFR-use changes in components over the same time period are shown in Table 5. By far the highest usage (ca. 25% of most models) of BFRs in vehicles is found in front seats from BFRs contained in the cover material or underlying foam. Since vehicle seats are covered with fabrics, vinyl, or leather, the XRF results obtained represent an average for a multilayer matrix Table 1: 2006 Model Year Number of Components with Br contents > 1,000 ppm