Novel flame retardants, 1,2-bis(2,4,6-tribromophenoxy)ethane and 2,3,4,5,6-pentabromoethylbenzene, in United States' environmental samples

Two brominated flame retardants, 1,2-bis(2,4,6-tribromophenoxy)ethane (TBE) and 2,3,4,5,6-pentabromoethylbenzene (PEB), were detected and identified in ambient air samples from various sites in the United States. The identifications were confirmed by comparing the gas chromatographic retention times and mass spectra of the compounds found in the environment with those of authentic materials. Generally, the TBE concentrations in air were comparable to those of tetra- through hexabrominated diphenyl ethers (PBDEs) and often higher than those of decabromodiphenyl ether (BDE-209). The atmospheric TBE concentrations at locations in the southern United States were higher than those in the northern United States. TBE was also found in a sediment core from Lake Michigan; the concentrations of TBE increased with time, were lower than those of BDE-209, but were approximately 10 times higher than the sum of BDE-47, -99, and -100. The maximum PEB concentration in Chicago air was 550 pg/ m3, which was 10 times higherthan the concentration of total PBDEs in this sample. In general, the concentrations of PEB in air samples were low but detectable and were less than those of PBDEs. PEB was not found in the sediment core from Lake Michigan. These occurrences of relatively high concentrations of TBE and PEB in environmental samples may reflect the increasing usage of these compounds as flame retardants.     

Brominated flame retardants in the atmosphere of the East-Central United States

Air samples were collected at five sites (urban, semiurban, agricultural, and remote) from Lake Michigan through the U. S. Midwest to the Gulf of Mexico every 12 days during 2002-2003 using high-volume samplers so that we could study the spatial trends of brominated flame retardants (polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs), and 1,2-bis(2,4,6-tribromophenoxy)-ethane (TBE)). The mean sigmaPBDE atmospheric concentration was 100 +/- 35 pg/m3 at the Chicago site, which was 3-6 times higher than that at the other sites. The sigmaPBDE atmospheric concentrations at the Chicago site were significantly higher than previous measurements made in 1997-1999. Unlike these former measurements, BDE-209 is now relatively abundant. Lower BDEs (tri- through hex-BDEs) were detected in both the particle and the gas phases, and the partitioning of these compounds between phases was highly dependent on atmospheric temperature. Higher BDEs (hepta- through deca-BDEs) were mostly detected in the particle phase. On the basis of the congener distributions in the samples, the concentrations were divided into three groups: penta-BDEs, octa-BDEs, and deca-BDEs. Penta-BDEs were the most concentrated at the Chicago site and the least concentrated at the Louisiana site; octa-BDE concentrations were low at all of the sites; deca-BDEs were the most concentrated at the Chicago site and notably high atthe Arkansas site. High concentrations of deca-BDEs, HBCDs, and TBE at the Arkansas site suggest that manufacturing areas in southern Arkansas could be the source regions. Backward trajectories for air masses with high concentrations of deca-BDEs coming to the Arkansas site suggestthat deca-BDEs bound to particles can move long distances from source regions to nonsource regions.     

Spray irrigation of treated municipal wastewater as a potential source of atmospheric PBDEs

Spray irrigation facilities utilizing treated municipal wastewater are a potential source of polybrominated diphenyl ethers (PBDEs) to the atmosphere. PBDEs are used as flame retardants in many household items and have been found in wastewaters and biosolids. Evidence of PBDE release from spray irrigation facilities was discovered during a multiyear project to measure semivolatile organic chemical concentrations in air. Four BDE congeners (47, 99, 100, and 154) were monitored at three remote/ rural locations in Maryland and Delaware from 2001 to 2003. Average concentrations at two of the sites (BDE-47, 10-17 pg/m3; BDE-99, 5.3-7.7 pg/m3) reflect background levels. Average concentrations at the third location were 5-10 times higher (BDE-47, 175 pg/m3; BDE-99, 26 pg/m3) and were significantly correlated (p < 0.0001) with temperature indicating local source(s). Several spray irrigation facilities are located south and west of the third site, the prevailing wind direction during the spring and summer when most samples were collected. The fine mist released from the irrigation equipment may enhance release to the atmosphere via air-water gas exchange from water droplets. Temporal trends indicate that aerial concentrations of PBDEs in this area are increasing at an exponential rate; the atmospheric doubling times for the different congeners range from 1.1 to 1.7 yrs.     

Air-water exchange and dry deposition of polybrominated diphenyl ethers at a coastal site in Izmir Bay, Turkey

The air-water exchange of polybrominated diphenyl ethers (PBDEs), an emerging class of persistent organic pollutants (POPs), was investigated using paired air-water samples (n = 15) collected in July and December, 2005 from Guzelyali Port in Izmir Bay, Turkey. Total dissolved-phase water concentrations of PBDEs (sigma7PBDEs) were 212 +/- 65 and 87 +/- 57 pg L(-1) (average +/- SD) in summer and winter, respectively. BDE-209 was the most abundant congener in all samples, followed by BDE-99 and -47. Average ambient gas-phase sigma7PBDE concentrations were between 189 +/- 61 (summer) and 76 +/- 65 pg m(-3) (winter). Net air-water exchange fluxes ranged from -0.9 +/- 1.0 (BDE-28) (volatilization) to 11.1 +/- 5.4 (BDE-209) ng m(-2) day(-1) (deposition). The BDE-28 fluxes were mainly volatilization while the other congeners were deposited. Gas- and dissolved-phase concentrations were significantly correlated (P = 0.33-0.55, p < 0.05, except for BDE-209, r = 0.05, p > 0.05) indicating thatthe atmosphere controls the surface water PBDE levels in this coastal environment. Estimated particulate dry deposition fluxes ranged between 2.7 +/- 1.9 (BDE-154) and 116 +/- 84 ng m(-2) day(-1) (BDE-209) indicating that dry deposition is also a significant input to surface waters in the study area.     

Dechlorane plus, a chlorinated flame retardant, in the Great Lakes

A highly chlorinated flame retardant, Dechlorane Plus (DP), was detected and identified in ambient air, fish, and sediment samples from the Great Lakes region. The identity of this compound was confirmed by comparing its gas chromatographic retention times and mass spectra with those of authentic material. This compound exists as two gas chromatographically separable stereoisomers (syn and anti), the structures of which were characterized by one- and two-dimensional proton nuclear magnetic resonance. DP was detected in most air samples, even at remote sites. The atmospheric DP concentrations were higher at the eastern Great Lakes sites (Sturgeon Point, NY, and Cleveland, OH) than those at the western Great Lakes sites (Eagle Harbor, MI, Chicago, IL, and Sleeping Bear Dunes, MI). Atthe Sturgeon Point site, DP concentrations once reached 490 pg/m3. DP atmospheric concentrations were comparable to those of BDE-209 at the eastern Great Lakes sites. DP was also found in sediment cores from Lakes Michigan and Erie. The peak DP concentrations were comparable to BDE-209 concentrations in the sediment core from Lake Erie butwere about 30 times lower than BDE-209 concentrations in the core from Lake Michigan. In the sediment cores, the DP concentrations peaked around 1975-1980, and the surficial concentrations were 10-80% of peak concentrations. Higher DP concentrations in air samples from Sturgeon Point, NY, and in the sediment core from Lake Erie suggest that DP's manufacturing facility in Niagara Falls, NY, may be a source. DP was also detected in archived fish (walleye) from Lake Erie, suggesting that this compound is, at least partially, bioavailable.     

Riverine inputs of polybrominated diphenyl ethers from the Pearl River Delta (China) to the coastal ocean

Riverine runoff is an important mode to transport anthropogenic pollutants from terrestrial sources to oceans. Polybrominated diphenyl ethers (PBDEs) were measured in riverine runoff samples from the eight major outlets within the Pearl River Delta (PRD), China, an economically fast developing region housing a vast number of electronics manufacturing and assembling plants. The sigma 17PBDEs (sum of 17 BDE congeners, i.e., BDE-28, -47, -66, -85, -99, -100, -138, -153, -154, -183, -196, -197, -203, -206, -207, -208, and -209) concentrations varied from 344 to 68,000 pg/L, with those of BDE-209, BDE-47, and BDE-99 being 335-65200, 3-143, and <1-200 pg/L, respectively. These levels were in the high end of the global PBDEs concentrations in the aquatic environments. The monthly inputs of sigma 17PBDEs ranged from 0.21 to 215 kg at individual outlets, and the annual input of sigma 17PBDEs from all the outlets was estimated at 2140 kg/year. Of the target BDE congeners, BDE-209 was the most predominant component with an annual input of 1960 kg/year, followed by BDE-47 (13.3 kg/year) and BDE-99 (11.7 kg/year). An extrapolation of the past use of PBDEs in the region concluded that 23 metric tons of sigma 17PBDEs have been discharged into the coastal ocean from the PRD in the last 20 years. The amount of PBDEs imported to China in the form of e-waste was estimated at 35000 metric tons/year, higher than the annual domestic production of brominated fire retardants (approximately 10000 metric tons/year) and the annual riverine input of total PBDEs from the PRD, suggesting that the majority of PBDEs inventory has been accumulated from importation of e-wastes. Because of the continuous importation of e-wastes and strong demand for brominated fire retardants, the impact of PBDEs on China's and the world's environments is expected to persist for many years to come.     

Brominated flame retardants in seawater and atmosphere of the Atlantic and the Southern Ocean

Seawater and air samples were collected aboard the FS Polarstern during the cruises ANT-XXV/1 + 2 in the Atlantic and Southern Ocean in 2008. The particulate and dissolved phase in water and particulate and gaseous phase in air were analyzed separately for nine polybrominated diphenyl ethers (PBDEs) and six non-PBDE brominated flame retardants (BFRs). Air concentrations of 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE) and hexabromobenzene (HBB) in the gaseous and particulate phase (median = 0.56 pg m(-3) for DPTE and 0.92 pg m(-3) for HBB) were comparable to ∑(9)PBDEs (1.0 pg m(-3)). Pentabromotoluene (PBT) was detectable in ～30% of the gaseous phase samples, whereas concentration of 2,4,6-tribromophenyl allylether (ATE), hexachlorocyclopentenyl-dibromocyclooctane (HCDBCO) and 2-ethyl-1-hexyl 2,3,4,5-tetrabromobenzoate (EHTBB) were below their method detection limits. DPTE, and PBDEs were also found in seawater at low pg per liter levels. Elevated seawater concentrations of PBDEs and DPTE were measured in the English Channel and close to South African coast. Concentrations of DPTE, BDE-47, and BDE-99 in the atmosphere generally decreased from Europe toward the Southern Ocean, whereas no latitudinal trend was observed in seawater. Air-water exchange gradients suggested net deposition dominates for all selected substances. The medians of net deposition fluxes for the air-water gas exchange were 83, 21, 69, 20, and 781 pg m(-2) day(-1) for BDE-47, BDE-100, BDE-99, DPTE, and HBB, whereas medians of dry deposition fluxes were 2.0, 0.3, 1.2, 1.0, and 0.5 pg m(-2) day(-1) for BDE-47, BDE-100, BDE-99, DPTE, and HBB. Overall, these results highlight the important role of the long-range atmospheric transport of PBDE and non-PBDE BFRs to remote regions.     

Tracking polybrominated diphenyl ether releases in a wastewater treatment plant effluent, Palo Alto, California

Polybrominated diphenyl ethers (PBDEs) are commonly used flame-retardants that are now ubiquitous environmental contaminants. Wastewater treatment plants are one source of PBDEs to the environment through their discharge of treated effluent and land application of sewage sludge. Effluent and sludge were collected and analyzed for PBDEs at a wastewater treatment plant in California. The total concentration of PBDEs ranged from 61 to 1440 microg/kg dry wt in the sludge and from 4 to 29,000 pg/L in discharged effluent. The congeners with the highest abundance in sludge were BDE-47, BDE-99, and BDE-209, while in treated effluent BDE-47 and BDE-99 were the most abundant. BDE-47 and BDE-99 are major congeners of the penta-formulation, while BDE-209 composes the deca-formulation. The sum of the major congeners in the penta-formulation (BDE-47, 99, 100, 153, and 154) comprises 88% of the total PBDEs in the effluent, while BDE-209 is only 6%. Based on the loading analysis, the total PBDE concentrations loaded to the San Francisco Estuary through effluent discharge from this wastewater treatment plant is 2 lb/year (0.9 kg/year).     

Concentration levels, compositional profiles, and gas-particle partitioning of polybrominated diphenyl ethers in the atmosphere of an urban city in South China

Air samples were collected in June of 2004 from four sites in the city of Guangzhou, a typical urban center in South China, to determine the levels, compositional profiles, and gas-particle distribution of 11 polybrominated diphenyl ether (PBDE) congeners (BDE-28, -47, -66, -100, -99, -85, -154, -153, -138, -183, and -209). The arithmetic mean atmospheric concentrations of sigmaPBDEs (sum of all target PBDE congeners except for BDE-209) in samples from the urban and city background sites were comparable to or slightly higher than those from other places around the world. The arithmetic mean atmospheric concentrations of BDE-209, however, were higherthan those in North America and Europe, and similar to the values from Japan. Congener compositions were dominated by BDE-209 in all (>70%) but an industrial site, with an average abundance of 48% for BDE-209. The PBDE patterns were generally similar to that in the technical penta-BDE mixture, Bromkal 70-5DE. Partitioning of PBDEs between the gas and particle phases (Kp) was well correlated with the subcooled liquid vapor pressure (PLO) for all of the samples, but the relationship differed between samples from different sites. The measured fractions of PBDEs in the particulate phase were compared to the predictions from the Junge-Pankow adsorption and KOA-based absorption models. The results indicated that the KOA-based model worked better than the Junge-Pankow model that tended to overestimate the particulate fractions for most PBDE congeners.     

Polybrominated diphenyl ethers in airborne particulates collected during a research expedition from the Bohai Sea to the Arctic

In July to September 2003, particulates in the oceanic atmosphere from the Bohai Sea to the high Arctic (37 degrees N to 80 degrees N) were collected aboard a research expedition icebreaker, Xuelong (Snow Dragon), under the 2003 Chinese Arctic Research Expedition Program (CHINARE 2003). These samples were analyzed to elucidate the atmospheric distributions of polybrominated diphenyl ethers (PBDEs) in the North Pacific Ocean and adjacent Arctic region. The levels of 11 PBDE congeners (BDE-28, -47, -66, -100, -99, -85, -154, -153, -138, -183, and -209; the sum was defined as sigma11PBDE) in the oceanic atmosphere of Far East Asia (34-48 degrees N/122-148 degrees E) ranged from 2.25 to 198.9 pg/m3 with a mean of 58.3 pg/m3. BDE-47, -99, -100, and -209 were the dominant congeners in all the samples, suggesting that the widely used commercial penta- and deca-BDE products were the original sources. The PBDE levels exhibited a decreasing trend from the mid- to high-latitudinal regions of the North Pacific Ocean, probably resulting from dilution, deposition, and decomposition of PBDEs during long-range transport of air masses. On the other hand, no apparent geographical pattern of PBDE distribution was observed within the Arctic, attributable to unstable air circulation and strong air mixing. Correlations among the PBDE congeners suggested that air masses collected from the North Pacific Ocean were relatively fresh, whereas those from the Arctic were aged as a result of photodecompoisiton. The higher average level (17.3 pg/m3) of PBDE congeners in the Arctic than those in the adjacent North Pacific Ocean (12.8 pg/m3) or other remote areas reported in the literature was attributed to the impact of the North American continent and temperature effects, which was consistent with the hypotheses of global fractionation.     

Distribution of polybrominated diphenyl ethers in sediments of the Pearl River Delta and adjacent South China Sea

Spatial and temporal distributions of polybrominated diphenyl ethers (PBDEs) in sediments of the Pearl River Delta (PRD) and adjacent South China Sea (SCS) of southern China were examined. A total of 66 surface sediment samples were collected and analyzed to determine the concentrations of 10 PBDE congeners (BDE-28, -47, -66, -100, -99, -154, -153, -138, -183, and -209). The concentrations of BDE-209 and SigmaPBDEs (defined as the sum of all targeted PBDE congeners except for BDE-209) ranged from 0.4 to 7340 and from 0.04 to 94.7 ng/g, respectively. The SigmaPBDEs concentrations were mostly < 50 ng/g, within the range for riverine and coastal sediments around the world, whereas the BDE-209 concentrations at the most contaminated sites were at the high end of the worldwide figures. Congener compositions were dominated by BDE-209 (72.6 - 99.7%), with minor contributions from penta- and octa-BDEs. Slightly different PBDE compositions were observed among samples collected from different locations, attributable to possible decomposition of highly brominated congeners and/or redistribution between particles of various sizes during atmospheric or fluvial transportation. The PBDE patterns in the SCS and Pearl River Estuary sediments were similar to those in sediments of the Zhujiang and Dongjiang Rivers, reflecting the widespread influence from local inputs. Analyses of two short sediment cores collected from the Pearl River Estuary showed that concentrations of BDE-209 rapidly increased in the upper layers of both cores, coincident with the growth of the electronics manufacturing capacities in the PRD region. The major sources of PBDEs were probably waste discharges from the cities of Guangzhou, Dongguan, and Shenzhen, the three fastest growing urban centers in the PRD.     

Indoor air is a significant source of tri-decabrominated diphenyl ethers to outdoor air via ventilation systems

Ventilation of indoor air has been hypothesized to be a source of PBDEs to outdoors. To study this, tri-decabrominated diphenyl ethers were analyzed in outgoing air samples collected inside ventilation systems just before exiting 33 buildings and compared to indoor air samples from microenvironments in each building collected simultaneously. Median ∑(10)PBDE (BDE- 28, -47, -99, -153, -183, -197, -206, -207, -208, -209) concentrations in air from apartment, office and day care center buildings were 93, 3700, and 660 pg/m(3) for outgoing air, and 92, 4700, and 1200 pg/m(3) for indoor air, respectively. BDE-209 was the major congener found. No statistically significant differences were seen for individual PBDE concentrations in matched indoor and outgoing air samples, indicating that outgoing air PBDE concentrations are equivalent to indoor air concentrations. PBDE concentrations in indoor and outgoing air were higher than published outdoor air values suggesting ventilation as a conduit of PBDEs, including BDE-209, from indoors to outdoors. BDE-209 and sum of BDE-28, -47, -99, and -153 emissions from indoor air to outdoors were roughly estimated to represent close to 90% of total emissions to outdoor air for Sweden, indicating that contaminated indoor air is an important source of PBDE contamination to outdoor air.     

Brominated flame retardants and dechlorane plus in the marine atmosphere from Southeast Asia toward Antarctica

The occurrence, distribution, and temperature dependence in the marine atmosphere of several alternative brominated flame retardants (BFRs), Dechlorane Plus (DP) and polybrominated diphenyl ethers (PBDEs) were investigated during a sampling cruise from the East Indian Archipelago toward the Indian Ocean and further to the Southern Ocean. Elevated concentrations were observed over the East Indian Archipelago, especially of the non-PBDE BFR hexabromobenzene (HBB) with concentrations up to 26 pg m(-3) which were found to be related to continental air masses from the East Indian Archipelago. Other alternative BFRs- pentabromotoulene (PBT), pentabromobenzene (PBBz), and 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE)-were elevated, too, with concentrations up to 2.8, 4.3, and 2.3 pg m(-3), respectively. DP was detected from 0.26 to 11 pg m(-3) and bis-(2-ethylhexyl)-tetrabromophthalate (TBPH) ranged from not detected (nd) to 2.8 pg m(-3), respectively. PBDEs ranged from nd to 6.6 pg m(-3) (Σ(10)PBDEs) with the highest individual concentrations for BDE-209. The approach of Clausius-Clapeyron (CC) plots indicates that HBB is dominated by long-range atmospheric transport at lower temperatures over the Indian and Southern Ocean, while volatilization processes and additional atmospheric emissions dominate at higher temperatures. In contrast, BDE-28 and -47 are dominated by long-range transport without fresh emissions over the entire cruise transect and temperature range, indicating limited fresh emissions of the meanwhile classic PBDEs.     

Size-dependent dry deposition of airborne polybrominated diphenyl ethers in urban Guangzhou, China

Gaseous and size-segregated particulate PBDEs (specifically BDE-47, -99, -183, -207, and -209) in the air were measured in urban Guangzhou at 100 and 150 m above the ground in daytime and at night in August and December 2010, to assess dry deposition of these contaminants accurately with regards to influences of meteorological factors but without confounding surface effects. Particulate PBDEs were more abundant at night than in daytime, and slightly higher in winter than in summer, likely from varying meteorological conditions and atmospheric boundary layers. More than 60% of particulate-phase PBDEs was contained in particles with an aerodynamic diameter (D(p)) below 1.8 μm, indicating long-range transport potential. The average daily particle dry deposition fluxes of PBDEs in August ranged from 2.6 (BDE-47) to 88.6 (BDE-209) ng m(-2) d(-1), while those in winter ranged from 2.0 (BDE-47) to 122 (BDE-209) ng m(-2) d(-1). Deposition fluxes of all PBDE congeners were significantly higher in daytime than at night for both months, due to the effect of diurnal variability of meteorological factors. In addition, mean overall particle deposition velocities of individual BDE congeners ranged from 0.11 to 0.28 cm s(-1). These values were within a factor of 2 of assumed values previously used in southern China and the Laurentian Great Lakes, suggesting that such assumptions were reasonable for sites with similar particulate size distributions and PBDE sources. Dry deposition velocities of PBDEs were lower at night than those in the daytime, probably reflecting higher mechanical and thermal turbulence during daytime. Dry deposition of particulate-bound PBDEs is influenced by short-term temporal variability from meteorological factors, and also by particulate size fractions.     

Atmospheric transport of polybrominated diphenyl ethers and polychlorinated biphenyls to the Baltic Sea

The atmospheric transport of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) was compared by measuring concentrations in air and deposition on an island located in the central basin of the Baltic Sea. Median sigmaPBDE and sigmaPCB concentrations (gaseous + particle) were 8.6 and 7.4 pg m(-3), respectively. Airborne PCBs were mainly found in the gaseous phase, while most of the PBDEs were detected on particles, which agrees with predicted particle/gas distributions. SigmaPBDE levels were dominated by the decabrominated BDE209 followed bythe tetrabrominated BDE47 and pentabrominated BDE99. BDE209 is a marker for the environmental distribution of the commercial deca-BDE formulation (>99.5% BDE209), whereas BDE47 and BDE99 are markers for the commercial penta-BDE mixture. General correlations between PBDEs and PCBs suggested similarities in sources and transport mechanism, while more detailed examination of the data identified notable behaviors and exceptions. Differences in regression slopes among tetra-, penta-, and decabrominated PBDEs may reflect different transport processes and the change in usage pattern. Tetra- and pentabrominated PBDEs may originate from secondary sources such as air surface exchange in a manner similar to that of the PCBs, while the deca-BDE209 formulation still has primary sources. The tribrominated BDE17 was also detected and is proposed to be a breakdown product due to atmospheric debromination processes. PBDEs had higher washout ratios than PCBs, explaining their higher concentrations compared to PCBs in precipitation (median of 6.0 and 0.5 ng L(-1) for sigmaBDE and sigmaPCB concentrations ("dissolved" + particle), respectively) than in air. The calculated yearly deposition of PBDEs and PCBs indicated that the atmospheric input of PBDEs to the Baltic Proper is currently exceeding that of the PCBs by a factor of 40, while that of the PCBs is decreasing.     

Polybrominated diphenyl ethers in peregrine falcon (Falco peregrinus) eggs from the northeastern U.S

A total of 114 peregrine falcon eggs from nests in Connecticut, Massachusetts, Maine, New Hampshire, Rhode Island, and Vermont were analyzed for polybrominanted diphenyl ethers (PBDEs). Eggs were collected from 1996 to 2006, excluding 1997 and 1998. Total PBDE concentrations ranged from 74.5 to 6610 ng/g wet weight, with a median of 440. These levels were generally higher than those observed in European peregrine eggs, but comparable to those in North American seabird eggs. Congener patterns differed from such seabirds and were dominated by BDE-153, followed by BDE-99, -183, -209, -197, -207, -154, -100, and -196; with lesser contributions from BDE-47, -208, -203, -201, -206, -202, -138, and -119. Urban and rural falcon eggs contained similar total PBDE concentrations but different congener profiles. Urban eggs exhibited higher BDE-209 concentrations and greater percentages of other highly brominated congeners. BDE-209 was detectable in all eggs, with concentrations ranging from 1.4 to 420 ng/g wet weight Five octa- and three nona-brominated congeners were also frequently detected, some likely derived from the biodegradation of BDE-209. Temporal analyses indicated no significant changes in concentrations of total PBDEs, or most individual congeners, during the study period. An exception was BDE-209. It exhibited a significant increase, with a doubling time of 5 years. Current PBDE burdens may be insufficient to cause noticeable adverse effects at the population level, as the number of territorial pairs increased in the past decade. However, the high BDE-209 concentrations, short doubling time, and likely biodegradation observed in peregrine eggs from the northeastern U.S. may supportthe need for additional deca-BDE regulations.     

Passive-sampler derived air concentrations of persistent organic pollutants on a north-south transect in Chile

Passive air samplers consisting of polyurethane foam (PUF) disks, were deployed in six locations in Chile along a north-south transect to investigate gas-phase concentrations of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs). The study provides new information on air concentrations of these persistent organic pollutants (POPs) which is lacking in this region. It also provides insight into potential sources and long-range transport (LRT). The samplers were deployed for a 2-month period in five remote sites and one site in the city of Concepción. Mean concentrations (pg m(-3)) for sigmaPCB were 4.7 +/- 2.7 at remote sites and 53 +/- 13 in Concepción. PCB levels at remote sites were related to proximity to urban source regions and/or air back trajectories. With the exception of endosulfan I, mean concentrations (pg m(-3)) of OCPs at background sites were consistently low: 5.4 +/- 1.4 for alpha-HCH, 7.0 +/- 1.1 for gamma-HCH, 2.5 +/- 0.5 for TC, 2.5 +/- 0.6 for CC, 1.9 +/- 1.2 for dieldrin, and less than 3.5 for toxaphene. Endosulfan I showed a decreasing concentration gradient from 99 to 3.5 pg m(-3) from the north to south of Chile. Concentrations of OCPs in the Concepción City were generally 10-20 times higher than at the background sites suggesting continued usage and/or re-emission from past use. For instance, at remote sites, the alpha/gamma ratio (0.76) was typical of background air, while the ratio in Concepción (0.12) was consistent with fresh use of gamma-HCH. Levels of sigmaPBDEs were below the detection limit of 6 pg m(-3) at all sites.     

2-Ethylhexyl tetrabromobenzoate and bis(2-ethylhexyl) tetrabromophthalate flame retardants in the Great Lakes atmosphere

Two relatively new flame retardants, 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB) and bis(2-ethylhexyl)-tetrabromophthalate (TBPH), were identified and quantitated in gas and particle-phase air samples collected from six sites near the shores of the Great Lakes. TBB and TBPH were detected in more than half of the samples collected from 2008 to 2010. Urban areas, such as Chicago and Cleveland, showed the highest concentrations (0.36-290 pg/m(3)), while remote areas, such as Eagle Harbor and Sleeping Bear Dunes, exhibited the lowest levels (0.050-32 pg/m(3)). The atmospheric concentrations of TBB and TBPH increased rapidly and significantly over this time period, perhaps indicating that these compounds are replacing the polybrominated diphenyl ethers (PBDEs), which have been removed or soon will be removed from the marketplace.     

Spatial distribution of polybrominated diphenyl ethers in southern Ontario as measured in indoor and outdoor window organic films

Organic films were collected from indoor and outdoor window surfaces, along an urban-rural transect extending northward from Toronto, Ontario, Canada, and analyzed for 41 polybrominated diphenyl ether congeners (PBDE). For exterior films, urban sigmaPBDE concentrations were approximately 10x greater than rural concentrations, indicating an urban-rural gradient and greater PBDE sources in urban areas. Urban films ranged from 2.5 to 14.5 ng/m2 (mean = 9.0 ng/ m2), excluding the regional "hotspot" Electronics Recycling Facility, compared to 1.1 and 0.56 ng/m2 at the Suburban and Rural sites. Interior urban films (mean = 34.4 ng/m2) were 3 times greater than rural films (10.3 ng/m2) and were representative of variations in building characteristics. Indoor films were 1.5-20 times greater than outdoor films, consistent with indoor sources of PBDEs and enhanced degradation in outdoor films. Congener profiles were dominated by BDE-209 (51.1%), consistent with deca-BDE as the main source mixture, followed by congeners from the penta-BDE mixture (BDE-99:13.6% and -47:9.4%) and some octa-BDE (BDE-183:1.5%). Congener patterns suggest a degradative loss of lower brominated compounds in outdoor films versus indoor films. Gas-phase air concentrations were back-calculated from film concentrations using the film-air partition coefficient (K(FA)). Mean calculated air concentrations were 4.8 pg/m3 for outdoor and 42.1 pg/m3 for indoor urban sites, indicating that urban indoor air is a source of PBDEs to urban outdoor air and the outdoor regional environment.     

Trophodynamics of polybrominated diphenyl ethers in the marine food web of Bohai Bay, North China

Polybrominated diphenyl ethers (PBDEs) are of great environmental concern due to the exponential increase of the concentrations in the environment, especially in high trophic level organisms, and the trophodynamics of these chemicals in aquatic food webs is an important criterion for assessing their ecological risk. This study analyzed 13 PBDEs in the zooplankton, five invertebrate species, six fish species, and one marine bird species collected from Bohai Bay. PBDE concentrations in organisms from Bohai Bay (sigmaPBDEs: 0.15-32.8 ng/g lipid weight) were low compared with other marine organisms worldwide, and BDE-47 wasthe predominant compound in most samples,followed by BDE-28, BDE-99/BDE-100, and BDE-119. Correlation between lipid-normalized concentrations of PBDEs, and trophic levels determined by stable nitrogen isotope technologies confirmed that PBDEs were biomagnified in the marine food web. Significantly positive relationships were found fortotal PBDEs and four PBDE compounds (BDE-28, BDE-47, BDE-100, and BDE-119), and their trophic magnification factors (TMFs) were 3.53, 3.57, 7.24, 3.23, and 2.60, respectively. The concentration ratios between congeners (BDE-99/BDE-100 and BDE-99/BDE-47) were found to decrease with increasing trophic levels, suggesting that trophic-level-dependent concentrations ratios between BDE-99 and BDE-100 would be contributed by trophic level-dependent biotransformation between BDE-99 and BDE-47, and therefore resulting in the dominance of BDE-100 compared with BDE-99 and the relatively high trophic magnification of BDE-47 in the marine food web.