Levels, tissue distribution, and age-related accumulation of synthetic musk fragrances in Chinese sturgeon (Acipenser sinensis): comparison to organochlorines

Chinese sturgeon (Acipenser sinensis) was listed as a Grade I protected animal in China in 1989, and the observed intersexual phenomenon and sex ratio deviation have suggested that chemicals have posed a risk as environment pollutants. This study analyzed seven musk fragrances in liver, muscle, heart, gonad, stomach, intestines, adipose, gill, pancreas, kidney, gallbladder, and roe from 13 female Chinese sturgeons, and the toxicokinetic behavior of musks were studied and compared with some organochlorines. Of the seven musks, HHCB, AHTN, and musk xylene were detected, and the highest concentrations were observed in adipose tissue: from 33.7 to 62.1 ng/g wet weight (ww), from 1.0 to 5.4 ng/g ww, and from 1.1 to 13 ng/g ww, respectively. Similar to the tissue distribution of DDTs and HCB, musks were detected frequently in high lipid content tissues such as roe, adipose, and liver, suggesting that tissue distribution of musks is controlled by the affinity to lipids. The concentration ratios based on lipid weight between roe and adipose were estimated to be 0.47 for HHCB, 0.58 for AHTN, and 0.51 for musk xylene, and those for the total DDTs and HCB were 0.27 and 0.61, which were relatively low compared with mammals. Relatively high concentrations of p,p'-DDE (68.4-449 ng/g ww) were detected in 10 of total 11 samples, which would cause the feminization of Chinese sturgeons during embryonic development. It was found that lipid-corrected concentrations of HHCB, AHTN, p,p'-DDE, and p,p'-DDD increased with age in female sturgeon, of which the trends were similar to those in fishes and different from those in mammals.     

One-step microwave-assisted headspace solid-phase microextraction for the rapid determination of synthetic polycyclic musks in oyster by gas chromatography–mass spectrometry

A rapid, simple and solvent-free procedure was developed for the determination of synthetic polycyclic musks in oyster samples by using one-step microwave-assisted headspace solid-phase microextraction (MA-HS-SPME) and gas chromatography–mass spectrometry (GC–MS). Two commonly used synthetic polycyclic musks, galaxolide (HHCB) and tonalide (AHTN), were selected in the method development and validation. The parameters (microwave irradiation power, extraction time, amount of water added, pH value and addition of NaCl) affecting the extraction efficiency of analytes from oyster slurry were systematically investigated and optimised. The best extraction conditions were achieved when the oyster tissue mixed with 10-mL deionised water (containing 3 g of NaCl in a 40-mL sample-vial) was microwave irradiated at 80 W for 5 min. The limit of quantification (LOQ) was 0.1 ng/g in 5-g of wet tissue. The good precision and accuracy of one-step MA-HS-SPME coupled with GC–MS for the determination of trace level of AHTN in oyster samples was also demonstrated.     

Air-sea exchange fluxes of synthetic polycyclic musks in the North Sea and the Arctic

Synthetic polycyclic musk fragrances Galaxolide (HHCB) and Tonalide (AHTN) were measured simultaneously in air and seawater in the Arctic and the North Sea and in the rural air of northern Germany. Median concentrations of gas-phase HHCB and AHTN were 4 and 18 pg m(-3) in the Arctic, 28 and 18 pg m(-3) in the North Sea, and 71 and 21 pg m(-3) in northern Germany, respectively. Various ratios of HHCB/AHTN implied that HHCB is quickly removed by atmospheric degradation, while AHTN is relatively persistent in the atmosphere. Dissolved concentrations ranged from 12 to 2030 pg L(-1) for HHCB and from below the method detection limit (3 pg L(-1)) to 965 pg L(-1) for AHTN with median values of 59 and 23 pg L(-1), respectively. The medians of volatilization fluxes for HHCB and AHTN were 27.2 and 14.2 ng m(-2) day(-1) and the depositional fluxes were 5.9 and 3.3 ng m(-2) day(-1), respectively, indicating water-to-air volatilization is a significant process to eliminate HHCB and AHTN from the North Sea. In the Arctic, deposition fluxes dominated the air-sea gas exchange of HHCB and AHTN, suggesting atmospheric input controls the levels of HHCB and AHTN in the polar region.     

Synthetic musk fragrances in human milk from the United States

Synthetic musk compounds are used as additives in many consumer products, including perfumes, deodorants, and detergents. Earlier studies have reported the occurrence of synthetic musks in environmental and wildlife samples collected in the United States. In this study, human breast milk samples collected from Massachusetts, were analyzed for the determination of concentrations of synthetic musks such as musk xylene (1-tert-butyl-3,5-dimethyl-2,4,6-trinitrobenzene), musk ketone (4-tert-butyl-2,6-dimethyl-3,5-dinitroacetophenone), HHCB (1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[gamma]-2-benzopyran), AHTN (7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene), and HHCB-lactone, the oxidation product of HHCB. In addition, we estimated the daily intake of synthetic musks by infants based on the ingestion rate of breast milk. Synthetic musks were found in most of the samples analyzed, and the concentrations ranged from < 2 to 150 ng musk xylene/g, < 2 to 238 ng musk ketone/ g, < 5 to 917 ng HHCB/g, < 5 to 144 ng AHTN/g, and < 10 to 88.0 ng HHCB-lactone/g, on a lipid weight basis. The concentrations of HHCB were higher than the concentrations of other synthetic musks in breast milk samples. The mean concentration of HHCB (220 ng/g, lipid weight) was 5 times greater than the concentrations reported 10 years ago for breast milk samples collected in Germany and Denmark. Maternal age was not correlated with the concentrations of musk xylene, musk ketone, HHCB, or AHTN. There was a trend of decreasing concentrations of musk xylene, musk ketone, HHCB, and AHTN, with the number of children previously breast-fed, although the correlation was not significant. Based on average daily ingestion rate of breast milk, an infant is estimated to ingest 297 +/- 229 ng musk xylene, 780 +/- 805 ng musk ketone, 1830 +/- 1170 ng HHCB, 565 +/- 614 ng AHTN, and 649 +/- 598 ng HHCB-lactone per day. The ingestion rate of synthetic musks by infants in the United States is lower than that estimated for persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs). Based on the residue patterns and accumulation features, it can be concluded that the exposure characteristics for synthetic musks are different from those of POPs, and that the major source of exposure to synthetic musks is probably via dermal absorption or inhalation.     

Temporal trends of synthetic musk compounds in mother's milk and associations with personal use of perfumed products

We analyzed two nitro musks (musk xylene and musk ketone) and five polycyclic musks (HHCB, AHTN, ADBI, ATII, and AHDI) in mother's milk from primiparae women (N = 101) living in Uppsala County, Sweden, 1996-2003. Possible temporal trends in musk concentrations and associations with lifestyle/medical factors, such as use of perfumed products during pregnancy were studied. HHCB showed the highest median concentration (63.9 ng/g lipid) followed by AHTN (10.4 ng/g) and musk xylene (MX) (9.5 ng/g). Concentrations of the other substances were, in most cases, below the quantification limit (2.0-3.0 ng/g). Women with a high use of perfume during pregnancy had elevated milk concentrations of HHCB, and elevated concentrations of AHTN were observed among women reporting use of perfumed laundry detergent. This strongly suggests that perfumed products are important sources of musk exposure both among the mothers and the nursed infants. Concentrations of AHTN and MX declined significantly between 1996 and 2003, suggesting a decline in the industrial use of the compounds in consumer products, or alterations in the consumer use pattern of perfumed products. No temporal trend in HHCB concentrations was seen. The lack of toxicity data makes it difficult to generalize about the safety of musk exposure of breast-fed infants.     

Behavior of the polycyclic musks HHCB and AHTN in lakes, two potential anthropogenic markers for domestic wastewater in surface waters

The synthetic polycyclic musks HHCB and AHTN are potential chemical markers for domestic wastewater contamination of surface waters. Understanding their environmental behavior is important to evaluate their suitability as markers. This study focuses on the quantification of the processes that lead to an elimination in lakes. Rate constants for all relevant processes were estimated based on laboratory studies and models previously described. In lake Zurich, during winter time, both compounds are eliminated primarily by outflowing water and due to losses to the atmosphere. In summer, direct photolysis represents the predominant elimination process for AHTN in the epilimnion of lake Zurich (quantum yield, 0.12), whereas for HHCB, photochemical degradation is still negligible. HHCB and AHTN were then measured in effluents of Swiss wastewater treatment plants (WWTPs), in remote and anthropogenically influenced Swiss surface waters, and in Mediterranean seawater using an analytical procedure based on SPE and GC-MS-SIM with D6-HHCB as internal standard (LODs for natural waters, 2 and 1 ng/L, respectively). In winter, concentrations of HHCB and AHTN in lakes (<2-47 and <1-18 ng/L, respectively) correlated with the anthropogenic burden by domestic wastewater (ratio population per water throughflow), demonstrating the suitability of these compounds as quantitative, source-specific markers. In summer, however, no such correlations were observed. Vertical concentration profiles in lake Zurich indicated significant losses in the epilimnion during summer, mainly for AHTN, and could be rationalized with a lake modeling program (MASASlight), considering measured, average loads from WWTP effluents (0.80 +/- 0.22 and 0.32 +/- 0.11 mg person(-1) d(-1) for HHCB and AHTN, respectively) and the estimated rate constants for elimination processes.     

In vitro and in vivo antiestrogenic effects of polycyclic musks in zebrafish

The polycyclic musks 6-acetyl-1,1,2,4,4,7-hexamethyltetraline (AHTN) and 1,2,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-gamma-2-benzopyran (HHCB) are used as fragrance ingredients in perfumes, soaps, and household cleaning products. They are known to be ubiquitously present in the aquatic environment, and because of their lipophilic nature, they tend to bioaccumulate in aquatic biota. In surface waters, concentrations between 1 ng/L and 5 microg/L have been found, depending mainly on the proportion of sewage effluents in the water. In fish, under normal environmental conditions, concentrations in the microgram per kilogram fresh weight (fw) range are found. In a previous study we showed that AHTN and HHCB exert mainly antiestrogenic effects on the human estrogen receptor alpha (ERalpha) and ERbeta in an in vitro reporter gene assay. In the current study, we assessed the in vitro antiestrogenic effects of both musks on zebrafish ERs. Antagonism was observed on zfERbeta, and more pronounced on the newly cloned zfERgamma. Using a transgenic zebrafish assay, we studied antiestrogenicity of the musks in vivo. Dose-dependent antagonistic effects were observed at concentrations of 0.1 and 1 microM AHTN and HHCB. GC-MS analysis showed that the musks bioaccumulated in the fish, with internal concentrations (15-150 mg/kg fw) which were roughly 600 times higher than the nominal test doses. To our knowledge, this is the first time that environmental contaminants are shown to be antiestrogenic in an in vivo fish assay that focuses solely on ER-mediated effects. This makes the transgenic zebrafish assay a promising tool for the rapid detection of both estrogenic and antiestrogenic effects of chemicals in fish.     

Occurrence of synthetic musk fragrances in marine mammals and sharks from Japanese coastal waters

In this study, the occurrence of the polycyclic musk fragrances HHCB (1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[g]-2-benzopyran) and AHTN (7-acetyl-1,1,3,4,4,6-hexamethyltetrahydeonaphthalene) in marine mammals and sharks collected from Japanese coastal waters is reported. HHCB was present in the blubbers of all finless porpoises (Neophocaena phocaenoides) analyzed (n = 8), at levels ranging from 13 to 149 ng/g on a wet weight basis. A fetus sample of finless porpoise contained a notable concentration of HHCB (26 ng/g wet wt), suggesting transplacental transfer of this compound. Among 12 tissues and organs of a finless porpoise analyzed, the highest HHCB concentration was found in blubber, followed by kidney. This indicates that HHCB accumulates in lipid-rich tissues in marine mammals, which is similar to the accumulation profiles of persistent organochlorines, such as PCBs and DDTs. In general, the residue levels of AHTN and nitro musks were low or below the detection limits in finless porpoises, implying either less usage in Japan or high metabolic capacity of these compounds in this animal. HHCB was also found in the livers of five hammerhead sharks (Sphrna lewini) from Japanese coastal waters, at concentrations ranging from 16 to 48 ng/g wet wt. Occurrence of HHCB in higher trophic organisms strongly suggests that it is less degradable in the environment and accumulates in the top predators of marine food chains. This is the first report on the accumulation of synthetic musk fragrances in marine mammals and sharks.     

Bioaccumulation, temporal trend, and geographical distribution of synthetic musks in the marine environment

Bioaccumulation of synthetic musks in a marine food chain was investigated by analyzing marine organisms at various trophic levels, including lugworm, clam, crustacean, fish, marine mammal, and bird samples collected from tidal flat and shallow water areas of the Ariake Sea, Japan. Two of the polycyclic musks, HHCB and AHTN, were the dominant compounds found in most of the samples analyzed, whereas nitro musks were not detected in any of the organisms, suggesting greater usage of polycyclic musks relative to the nitro musks in Japan. The highest concentrations of HHCB were detected in clams (258-2730 ng/g lipid wt.), whereas HHCB concentrations in mallard and black-headed gull were low, and comparable with concentrations in fish and crab. These results are in contrast to the bioaccumulation pattern of polychlorinated biphenyls; for which a positive correlation between the concentration and the trophic status of organisms was found. Such a difference in the bioaccumulation is probably due to the metabolism and elimination of HHCB in higher trophic organisms. Temporal trends in concentrations of synthetic musks were examined by analyzing tissues of marine mammals from Japanese coastal waters collected during 1977-2005. HHCB concentrations in marine mammals have shown significant increase since the early 1990s, suggesting a continuous input of this compound into the marine environment. Comparison of the time trend for HHCB with those for PCBs and PBDEs suggested that the rates of increase in HHCB concentrations were higher than the other classes of pollutants. To examine the geographical distribution of HHCB, we have analyzed tissues of fish, marine mammals, and birds collected from several locations. Synthetic musks were not detected in a sperm whale (pelagic species) from Japanese coastal water and in eggs of south polar skua from Antarctica. While the number of samples analyzed is limited, these results imply a lack of long-range transportation potential of synthetic musks in the environment.     

Synthetic musk fragrances in Lake Michigan

Synthetic musk fragrances are added to a wide variety of personal care and household products and are present in treated wastewater effluent. Here we report for the first time ambient air and water measurements of six polycyclic musks (AHTN, HHCB, ATII, ADBI, AHMI, and DPMI) and two nitro musks (musk xylene and musk ketone) in North America. The compounds were measured in the air and water of Lake Michigan and in the air of urban Milwaukee, WI. All of the compounds except DPMI were detected. HHCB and AHTN were found in the highest concentrations in all samples. Airborne concentrations of HHCB and AHTN average 4.6 and 2.9 ng/m3, respectively, in Milwaukee and 1.1 and 0.49 ng/m3 over the lake. The average water concentration of HHCB and AHTN in Lake Michigan was 4.7 and 1.0 ng/L, respectively. A lake-wide annual mass budget shows that wastewater treatment plant discharge is the major source (3470 kg/yr) of the synthetic musks while atmospheric deposition contributes less than 1%. Volatilization and outflow through the Straits of Mackinac are major loss mechanisms (2085 and 516 kg/yr for volatilization and outflow, respectively). Concentrations of HHCB are about one-half the predicted steady-state water concentrations in Lake Michigan.     

Polybrominated diphenyl ethers in marine species from the Belgian North Sea and the Western Scheldt Estuary: levels, profiles, and distribution

The Western Scheldt Estuary (SE) is subjected to a variety of suspected PBDE sources, such as a brominated flame retardant manufacturing plant, the Antwerp harbor, and the textile industry located further upstream the river. The Belgian North Sea (BNS) was included in this study to analyze the influence of the SE on the levels found in biota from the BNS locations. Benthic invertebrates, such as shrimp, crab, and starfish, benthic fish, such as goby, dab, plaice, and sole, and gadoid fish, such as bib and whiting, were sampled in the BNS (nonpolluted area) and the SE (polluted area) and analyzed to determine the concentrations and spatial variation of eight polybrominated diphenyl ethers (PBDEs 28, 47, 99, 100, 153, 154, 183, and 209). Levels found in the SE samples were up to 30 times higher than those found in BNS samples, with a gradient increasing toward Antwerp. Levels in BNS ranged from 0.02 to 1.5 ng/g ww in benthic invertebrates and goby, from 0.06 to 0.94 ng/g ww in fish muscle, and from 0.84 to 128 ng/g ww in fish liver. For the SE samples, levels ranged from 0.20 to 29.9 ng/g ww in benthic invertebrates and goby, from 0.08 to 6.9 ng/g ww in fish muscle, and from 15.0 to 984 ng/g ww in fish liver. BDE 209 could only be detected in eight liver samples from the SE and levels ranged between 3.4 and 37.2 ng/g ww. PBDE profiles of the various species at the different locations were compared. Differences in profile were attributed to different exposure and to differences in metabolism among species. Ratios between BDE 99 and 100 were found to be highly location and species dependent, which could be related to differences in metabolism. Some species, such as dab, plaice bib, and whiting, showed preferential accumulation of PBDEs in the liver. Higher brominated congeners in general showed higher affinity for liver than for muscle tissue.     

Biomagnification of perfluoroalkyl compounds in the bottlenose dolphin (Tursiops truncatus) food web

The environmental distribution and the biomagnification of a suite of perfluoroalkyl compounds (PFCs), including perfluorooctane sulfonate (PFOS) and C8 to C14 perfluorinated carboxylates (PFCAs), was investigated in the food web of the bottlenose dolphin (Tursiops truncatus). Surficial seawater and sediment samples, as well as zooplankton, fish, and bottlenose dolphin tissue samples, were collected at two U.S. locations: Sarasota Bay, FL and Charleston Harbor, SC. Wastewater treatment plant (WWTP) effluents were also collected from the Charleston area (n = 4). A solid-phase extraction was used for seawater and effluent samples and an ion-pairing method was used for sediment and biotic samples. PFCs were detected in seawater (range <1-12 ng/L), sediment (range <0.01-0.4 ng/g wet weight (ww)), and zooplankton (range 0.06-0.3 ng/g ww). The highest PFC concentrations were detected in WWTP effluents, whole fish, and dolphin plasma and tissue samples in which PFOS, C8 and C10-PFCAs predominated in most matrices. Contamination profiles varied with location suggesting different sources of PFC emissions. Biomagnification factors (BMFs) ranged from <1 to 156 at Sarasota Bay and <1 to 30 at Charleston. Trophic magnification factors (TMFs) for PFOS and C8-C11 PFCAs indicated biomagnification in this marine food web. The results indicate that using plasma and liver PFC concentrations as surrogate to whole body burden in a top marine predator overestimates the BMFs and TMFs.     

Analysis of polychlorinated biphenyls, pyrethroid insecticides and fragrances in human milk using a laminar cup liner in the GC injector

 Since 1970 the State Laboratory of Basle City has been periodically analyzing human milk from the region (the latest in 1998/99) as a bioindicator for the environmental load of organochlorine pesticides [1, 2]. The analysis of human milk is very complex including several clean-up steps and is therefore time consuming. The focus is mainly on organochlorine pesticides, polychlorinated biphenyls (PCB), and nitro-musk compounds; analytes which are easily detectable with gas chromatography and electron capture detection (ECD). Our aim was to minimize the clean-up steps for the analysis of ECD sensitive substances. Furthermore, analytes insensitive to EC detection that require MS detection, such as polycyclic musk substitutes, were of interest. With the help of a specially designed GC liner in the vaporizing injector of the gas chromatograph, the laminar cup liner, we have considerably reduced the time and effort in the sample preparation. With the described clean-up procedure we analyzed 53 human milk samples from the region of Basle for PCB, pyrethrins, and pyrethroid insecticides and fragrances (nitro-musk compounds and polycyclic musk substitutes). While PCB showed a general downward trend in mean concentrations since 1980, residues of the polycyclic musk substitutes galaxolide and tonalide were detectable in almost every sample (e.g., 73 μg/kg fat of HHCB, 74 μg/kg fat of AHTN). Pyrethrins and pyrethroid insecticides were detected only at low concentrations between 0.03 and 0.46 mg/kg fat. Received: 28 September 1999 / Revised version: 2 May 2000     

Synthetic musk fragrances in Lake Erie and Lake Ontario sediment cores

Two sediment cores collected from Lake Ontario and Lake Erie were sectioned, dated, and analyzed for five polycyclic musk fragrances and two nitro musk fragrances. The polycyclic musk fragrances were HHCB (Galaxolide), AHTN (Tonalide), ATII (Traseolide), ADBI (Celestolide), and AHMI (Phantolide). The nitro musk fragrances were musk ketone and musk xylene. Chemical analysis was performed by gas chromatography/mass spectrometry (GC/MS), and results from Lake Erie were confirmed using gas chromatography/triple-quadrupole mass spectrometry (GC/MS/MS). The chemical signals observed at the two sampling locations were different from each other primarily because of large differences in the sedimentation rates at the two sampling locations. HHCB was detected in the Lake Erie core whereas six compounds were detected in the Lake Ontario core. Using measured fragrance and 210Pb activity, the burden of synthetic musk fragrances estimated from these sediment cores is 1900 kg in Lake Erie and 18 000 kg in Lake Ontario. The input of these compounds to the lakes is increasing. The HHCB accumulation rates in Lake Erie for 1979-2003 and 1990-2003 correspond to doubling times of 16 +/- 4 and 8 +/- 2 years, respectively. The results reflect current U.S. production trends for the sum of all fragrance compounds.     

Biomagnification of perfluorinated compounds in a remote terrestrial food chain: Lichen-Caribou-wolf

The biomagnification behavior of perfluorinated carboxylates (PFCAs) and perfluorinated sulfonates (PFSAs) was studied in terrestrial food webs consisting of lichen and plants, caribou, and wolves from two remote northern areas in Canada. Six PFCAs with eight to thirteen carbons and perfluorooctane sulfonate (PFOS) were regularly detected in all species. Lowest concentrations were found for vegetation (0.02-0.26 ng/g wet weight (ww) sum (Σ) PFCAs and 0.002-0.038 ng/g ww PFOS). Wolf liver showed highest concentrations (10-18 ng/g ww ΣPFCAs and 1.4-1.7 ng/g ww PFOS) followed by caribou liver (6-10 ng/g ww ΣPFCAs and 0.7-2.2 ng/g ww PFOS). Biomagnification factors were highly tissue and substance specific. Therefore, individual whole body concentrations were calculated and used for biomagnification and trophic magnification assessment. Trophic magnification factors (TMF) were highest for PFCAs with nine to eleven carbons (TMF = 2.2-2.9) as well as PFOS (TMF = 2.3-2.6) and all but perfluorooctanoate were significantly biomagnified. The relationship of PFCA and PFSA TMFs with the chain length in the terrestrial food chain was similar to previous studies for Arctic marine mammal food web, but the absolute values of TMFs were around two times lower for this study than in the marine environment. This study demonstrates that challenges remain for applying the TMF approach to studies of biomagnification of PFCAs and PFSAs, especially for terrestrial animals.     

Polycyclic musk fragrances in fish samples from Berlin waterways, Germany.

The contamination of different fish species by polycyclic musks [Galaxolide (HHCB), Tonalide (AHTN), Celestolide (ADBI), Phantolide (AHMI), and Traesolide (ATII) within the frame work of an exposure monitoring programme are reported. A total of 341 fish samples were taken from three waterways in Berlin known to be contaminated to different extents with sewage. The mean levels of musk fragrance compounds reported on a whole weight basis in fish samples were as follows for the most common polycyclic compound, HHCB, in samples (taken from edible parts) of eel caught in waters strongly polluted with sewage levels were 1513 microg/kg (6471 microg/kg lipid) (AHTN: 726 microg/kg and from slightly polluted waters 52 microg/kg (445 microg/kg lipid) (AHTN: only one value above the detection limit). Median concentrations in fish samples were: perch 200 microg/kg (33.3 mg/kg lipid) common bream 1571 microg/kg (90.1 mg/kg lipid), roach 168 microg/kg (13.0 mg/kg lipid), pike 366 and 370 microg/kg (66.5 and 61.7 mg/kg lipid) and for pike perch 190 microg/kg (47.3 mg/kg lipid). ADBI, AHMI and ATII could be determined only in low concentrations (<10% of the total contents of polycyclics in eel). Clear concentration differences were seen between fish samples from waters contaminated at different levels within the programme of biomonitoring. This demonstrated that polycyclic musks are a very good indicator of the level of contamination of a waterway with sewage. Human exposure to these musk fragrances from consumption of contaminated fish was estimated to be low in comparison to direct dermal absorption from the use of fragrance products.     

Determination of brominated flame retardants and brominated dioxins in fish collected from three regions of Japan

The concentrations of brominated dioxins which are polybrominated dibenzo-p-dioxins/polybrominated dibenzofurans (PBDD/DFs) and mono-bromo polychlorinated dibenzo-p-dioxins/dibenzofurans, polybrominated diphenyl ethers (PBDEs) and tetrabromobisphenol A (TBBPA) were investigated in a total of 45 fish samples collected from three regions in Japan. In the brominated dioxins, 1,2,3,4,6,7,8-heptabromodibenzofuran (HpBDF) was the most abundant congener, and it was found in seven fish samples at 0.10-25.6 pg/g wet weight (ww). The highest concentration of 1,2,3,4,6,7,8-HpBDF was found in the pike eel. Regarding other congeners, 2,3,7,8-tetrabromodibenzo-p-dioxin was detected in the sea bream at 0.02 pg/g ww, and 2,3,7,8-tetrabromodibenzofuran was detected in the conger eel at 0.03 pg/g ww. 3-Bromo-2,7,8-trichlorodibenzofuran was detected in the Sardinella zunasi and the conger eel at 0.01 pg/g ww and 0.02 pg/g ww, respectively. Using toxic equivalency factors of chlorinated dioxins, we calculated the PBDD/DFs concentrations of these fish samples at 0.001-0.256 pg TEQ/g ww. PBDEs were detected in all of the fish samples. The concentrations of total PBDEs were 0.01-2.88 ng/g ww. The seerfish and the yellowtail containd PBDEs in high concentrations. The most dominant congener in most of the fish was 2,2',4,4'-tetrabromo diphenyl ether. TBBPA was detected in 29 fish samples at 0.01-0.11 ng/g ww. The mean level of TBBPA was about one-tenth or less of the total level of PBDEs. A good correlation was obtained between total PBDEs and fat content. On the other hand, no correlation was obtained between TBBPA and fat content. The daily intakes from fish were estimated to be 0.58 ng/kg body weight (bw)/day for total PBDEs, 0.03 ng/kg bw/day for TBBPA, and 0.01 pg TEQ/kg bw/day for brominated dioxins in the case assuming that the average bw of a Japanese adult person is 50 kg and that the average fish consumption is 82 g/day. For PBDEs, the provisionally calculated value was much less than the lowest observed adverse effect level value (1 mg/kg bw/day). For brominated dioxins, the daily intake was at a very low level compared with the Japanese daily intake of polychlorinated dioxins from fish. Even if the value of PBDD/DFs is added to the amount of chlorinated dioxin exposure, it was estimated that it is less than the tolerable daily intake (4 pg TEQ/kg bw/day) in Japan.     

Biological monitoring of polyfluoroalkyl substances: A review

Polyfluoroalkyl substances (PFSs) are used in industrial and commercial products and can degrade to persistent perfluorocarboxylates (PFCAs) and perfluoroalkyl sulfonates (PFSAs). Temporal trend studies using human, fish, bird, and marine mammal samples indicate that exposure to PFSs has increased significantly over the past 15-25 years. This review summarizes the biological monitoring of PFCAs, PFSAs, and related PFSs in wildlife and humans, compares concentrations and contamination profiles among species and locations, evaluatesthe bioaccumulation/biomagnification in the environment, discusses possible sources, and identifies knowledge gaps. PFSs can reach elevated concentrations in humans and wildlife inhabiting industrialized areas of North America, Europe, and Asia (2-30,000 ng/ mL or ng/g of wet weight (ww)). PFSs have also been detected in organisms from the Arctic and mid-ocean islands (< or = 3000 ng/g ww). In humans, PFSAs and PFCAs have been shown to vary among ethnic groups and PFCA/PFSA profiles differ from those in wildlife with high proportions of perfluorooctanoic acid and perfluorooctane sulfonate. The pattern of contamination in wildlife varied among species and locations suggesting multiple emission sources. Food web analyses have shown that PFCAs and PFSAs can bioaccumulate and biomagnify in marine and freshwater ecosystems. Knowledge gaps with respect to the transport, accumulation, biodegradation, temporal/spatial trends and PFS precursors have been identified. Continuous monitoring with key sentinel species and standardization of analytical methods are recommended.     

Current-use flame retardants in the eggs of herring gulls (Larus argentatus) from the Laurentian Great Lakes

Of the 13, current-use, non-polybrominated diphenyl ether (PBDE) flame retardants (FRs) monitored, hexabromobenzene (HBB), pentabromoethylbenzene (PBEB), pentabromotoluene (PBT), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) and alpha- and gamma-isomers of hexabromocyclododecane (HBCD), and the syn- and anti-isomers of the chlorinated Dechlorane Plus (DP) were quantified in egg pools of herring gulls (Larus argentatus) collected in 2004 from six sites in all five of the Laurentian Great Lakes of North America. alpha-HBCD concentrations ranged from 2.1 to 20 ng/g (wet weight (ww)). Other "new" FR levels ranged from 0.004 to 1.4 ng/g ww and were much lower than those of the major BDE congeners that are in technical mixtures (namely BDE-47, -99, -100), where sigma3PBDE ranged from 186 to 498 ng/g ww. Nineteen hepta-BDEs (sigma(hepta) = 4.9-11 ng/g ww), octa-BDEs (alpha(octa) = 2.6-9.1 ng/g ww), and nona-BDEs (sigma(nona) = 0.12-5.6 ng/g ww) were detectible at all six colonies, while BDE-209 was low but quantifiable (< 0.1-0.21 ng/g ww) at two colonies. sigma-DP (syn- and anti-isomers) concentrations in eggs from all sites ranged from 1.5 to 4.5 ng/g ww. Our findings indicate that mother herring gulls are exposed to several, current-use flame retardants via their diet, and in ovo transfer occurred to their eggs. Given the aquatic diet of herring gull, this suggests that there are non-PBDE BFRs present in the gull-associated aquatic food web of the Great Lakes.     

Biotransformation of the polycyclic musks HHCB and AHTN and metabolite formation by fungi occurring in freshwater environments

Micropollutants found in aquatic environments have increasingly raised concerns with respect to their uncertain environmental fate and potentially adverse effects on human health and the environment. The biodegradability of two major representatives of the polycyclic musk fragrances, Galaxolide (HHCB) and Tonalide (AHTN), and the formation of biotransformation metabolites, were investigated with Myrioconium sp. strain UHH 1-13-18-4 and Clavariopsis aquatica, two mitosporic fungi derived from freshwater environments. A particular focus was to assess the effects of extracellular oxidoreductases such as laccases, which are produced by the investigated fungi under certain conditions, on HHCB and AHTN. The fungi converted HHCB and AHTN into various products via initial hydroxylation at different carbon positions. Further metabolism resulted in the subsequent formation of diketone, peroxide, and O-methylated derivatives. Isolated laccases of the investigated fungi were able to oxidize HHCB and AHTN and catalyzed the formation of the metabolite HHCB-lactone from HHCB. At particular environmental situations also specified within the present study, biotransformations catalyzed by fungi occurring in freshwater environments may be considered when addressing the fate of polycyclic musks in freshwater systems and potential biological effects of their degradation metabolites.