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1.
It has been hypothesized that a principal route of human exposure to polybrominated diphenyl ethers (PBDEs), used as flame retardants, is through fish consumption. Between 1999 and 2005 PBDE-47, -99, -100, -153, and -154 were analyzed in 3797 biological samples of 33 species of the Hudson River, New York. Approximately 98.4% of the samples contained PBDEs between 0.5 and 37 169 ng g(-1) lipid, with a median concentration of 772 ng g(-1) lipid. Yearly median sigmaPBDE concentrations fluctuated. Samples from river miles 112 and 153 contained higher sigmaPBDEs than those from other locations of the river. The 7-year median sigmaPBDE concentrations were the highest in large carnivorous fishes and the lowest in insects. The median abundance of congener PBDE-47 decreased from 80% to 63% with decreasing levels of sigmaPBDEs in the samples, while an increase from 2% to 23% was observed for PBDE-99. The median abundance of other congeners did not change with concentrations of sigmaPBDEs. Positive-, negative-, and no-correlation between sigmaPBDE concentrations and fish weight were observed for different species and for the same species from different locations of the river. The sources of PBDE contamination, diet, metabolic activity, and sediment chemistry might affect the levels of PBDEs in a fish.  相似文献   

2.
Brominated flame retardants in sediment cores from Lakes Michigan and Erie   总被引:5,自引:0,他引:5  
The history of polybrominated diphenyl ethers (PBDEs) and the major polybrominated biphenyl congener (BB-153) was studied in dated sediment cores taken from Lakes Michigan and Erie. The surficial concentration of total PBDE (65 [corrected] ng/g dry weight) in Lake Michigan was about 1.6 [corrected] times higher than that in Lake Erie (40 ng/g) and about 5 times higher than that [corrected] in Lake Superior (approximately 12 ng/g). The concentrations of total PBDEs in these sediments have increased rapidly, with doubling times of 5-10 years, reflecting the increasing market demand for these flame retardants over the last 30 years. BDE-209 was found to be the predominant congener in both sediment cores, making up approximately 95% [corrected] of the total PBDE load. The inventories of total PBDEs in Lakes Michigan and Erie were both [corrected] 40 ng/cm2 [corrected] The total burdens of these compounds in the sediment of Lakes Michigan and Erie were 23 [corrected] and 10 metric tons, respectively. We estimate [corrected] the total burden of these compounds in all of the Great Lakes is on the order of 100 [corrected] tons. In both lakes, BB-153 was found to increase rapidly during the 1970s and to peak around 1980.  相似文献   

3.
To explore the geographical distribution and temporal trends of polybrominated diphenyl ethers (PBDEs) in the Great Lakes, lake trout from Lakes Superior, Michigan, Huron, and Ontario and walleye from Lake Erie, collected during the period of 1980-2000, were analyzed. The concentrations of fifteen PBDE congeners and one polybrominated biphenyl (PBB-153) were determined in each fish sample. Lake trout from Lakes Michigan and Ontario had the highest sigmaPBDE concentrations during the years investigated. The sigmaPBDE concentrations in fishes from the five lakes increased exponentially with time, doubling every 3-4 years. The relative proportion of BDEs-47, -99, and -100 compared to BDEs-153 and -154 increased significantly as a function of time. Over the period 1980-2000, the concentrations of PBB-153, which was a component of a flame retardant banned in the 1970s, generally remained the same in these Great Lakes fishes, except for lake trout from Lake Huron, where the PBB-153 concentrations decreased significantly, but slowly.  相似文献   

4.
Few data are available on brominated flame retardants (BFRs) in terrestrial mammalian wildlife. Moreover, the use of hair in nondestructive monitoring of BFRs in mammals or humans has not been investigated. In the present study, concentrations of polybrominated diphenyl ethers (PBDEs) and brominated biphenyl 153 (BB 153) were analyzed in tissues of the European hedgehog Erinaceus europaeus. Road kills and carcasses from wildlife rescue centers were used to investigate relationships between concentrations of BFRs in hair and internal tissues, BFR tissue distribution (hair, liver, kidney, muscle, and adipose tissue), and PBDE congener tissue pattern dissimilarities. Liver concentrations of PBDEs and BB 153 were in the ranges 1-1178 and 0-2.5 ng/g of liver wet weight, respectively. PBDEs were predominant in adipose tissue and liver, while accumulation of BB 153 was tissue independent. The less persistent compound BDE 99 was more dominant in hair than in internal tissues. We observed positive relationships between BFR levels in hair and internal tissues for sum PBDEs and BDE 47 (0.37 < r < 0.78). The present study demonstrated that hair is a suitable indicator of PBDE exposure in terrestrial mammals which can be used in nondestructive monitoring schemes.  相似文献   

5.
Brominated flame retardants in tree bark from North America   总被引:2,自引:0,他引:2  
Brominated flame retardants were measured in 87 tree bark samples from 29 locations in North America. The concentrations of total polybrominated diphenyl ethers (PBDEs) ranged from 2.3 to 5700 ng/g lipid weight, with the highest concentrations found near or in Arkansas. A simple radial dilution model nicely describes the distribution of total PBDE concentrations in these samples and indicates the likely sources ofthese chemicals are emissions from the two brominated flame retardant manufacturing facilities, operated by Great Lakes Chemicals and Albemarle, located in southern Arkansas. The congener profiles of PBDEs are similar for all the tree bark samples and can be described by a mixture of the congener profiles of the penta- and deca-BDE commercial products combined in a ratio of 1:2. Two unusual BFRs, 1,2-bis(2,4,6-tribromophenoxy)ethane and decabromodiphenyl ethane, were also detected in tree bark samples collected in Arkansas, suggesting the two manufacturing facilities are the sources of these compounds as well. A polybrominated biphenyl congener (BB-153) was present in most tree bark samples at low levels relative to the PBDEs.  相似文献   

6.
A time trend between 1986 and 2003 was found for brominated flame retardants in peregrine falcon eggs from South Greenland, with significantly increasing concentrations of the polybrominated diphenyl ethers (PBDEs) 99, 100, 153, 154, and 209. For BDE-99 and -100, the concentration increased approximately 10% per year. The concentrations of PBDEs were among the highest detected in wildlife so far and ranged from 300 to 12,900 ng/g lipid weight (lw) for sigmaPBDE. While tetrabromobisphenol A (TBBPA) was below the limit of detection in all eggs, hexabromocyclododecane (HBCD), dimethyl-TBBPA, and brominated biphenyl BB-153 were detected in a majority of eggs, with median concentrations of 2.4, 230, and 550 ng/g lw, respectively. Analyses of eggs of the same bird showed no significant intra-clutch variation for PBDEs, BB-153, and HBCD but larger variations for dimethyl-TBBPA. Inter-clutch variations with increasing time trends exist for the BDEs 99, 100, 153, 154, and 209, while a decreasing contamination with the BDEs 183, 49, 47, 66 and 153 was indicated in a subset of eggs.  相似文献   

7.
Several brominated flame retardants (BFRs) were analyzed in peregrine falcon eggs collected in 1987-1999, including the constituents of the technical polybrominated diphenyl ether (PBDE) products Penta (BDE-47, -99, -100, -153, -154), Octa (BDE-183), and Deca (BDE-209), hexabrominated biphenyl (BB-153), and hexabromocyclododecane (HBCD). The eggs represented females from three different breeding populations, northern Sweden, southwestern Sweden, and a captive breeding population. All BFRs analyzed for were found, including BDE-183 and -209, and concentrations were much higher in wild falcons (geometric mean sigmaPBDE, BB-153, and HBCD for northern/southern populations of 2200/2700, 82/77, and 150/250 ng/g lw, respectively) than in captive falcons (39, 8 ng/g lw, and not detected, respectively). This is the first time, to our knowledge, that BDE-183 and -209 have been quantified in high trophic level wildlife.  相似文献   

8.
Congener-specific accumulation and prey to predator transfer of 22 polybrominated diphenyl ethers (PBDEs) were assessed in polar cod, ringed seal, polar bear, and beluga whale. Although the concentrations found were relatively low, these results show that PBDEs have reached the Arctic. PBDE congeners 47, 99, and 100 were dominant in all species studied. The pattern in ringed seal was somewhat simpler than in polar cod, with PBDE 47 accounting for more than 90% of the total PBDEs. In contrast, beluga whales, feeding on prey similar to that of ringed seals, showed higher PBDE levels and a more complex PBDE pattern than ringed seals. In contrast, polar bears contained only PBDE 47 in relatively small amounts. These differences in levels and patterns are likely due to species-specific differences in PBDE metabolism and accumulation. The metabolic index suggested that PBDEs 47 and 99 accumulate to the same magnitude as PCB 153 (PCB = polychlorinated biphenyl) in ringed seals and beluga whales. In contrast to beluga whales, ringed seals can metabolize PBDE 100 to some extent. Polar bears are seemingly capable of metabolizing virtually all PBDEs and are therefore unsuitable as indicators for PBDE contamination in the environment.  相似文献   

9.
The polybrominated diphenyl ethers (PBDEs) are widely used as flame retardants in plastics of soft furnishings, TV sets and computers, and insulation in the indoor environment. The penta-BDEs--now banned in most parts of Europe but still used in North America--are additive flame retardants that may be released to the indoor environment via volatilization or as dusts. In this study, to investigate general population PBDE exposure, air was sampled in 74 randomly selected homes in Ottawa, Canada and at seven outdoor sites during the winter of 2002--3, using polyurethane foam (PUF) disk passive air samplers. The passive sampling rate (2.5 m3 day(-1)) was determined through a pilot study employing active and passive samplers side-by-side at selected indoor locations. Indoor air concentrations of PBDEs were log-normally distributed with a geometric mean of 120 pg m(-3) and a median of 100 pg m(-3), approximately 50 times higher than the range of outdoor air concentrations (<0.1-4.4 pg m(-3)). The maximum daily human exposure via the inhalation pathway based on median PBDE levels found in this survey was estimated to be 1.9 ng day(-1) (female) and 2.0 ng day(-1) (male), representing 4.1% (f) and 4.4% (m) of overall daily intake.  相似文献   

10.
Temporal, spatial, and interspecific trends in polybrominated diphenyl ether (PBDE) flame retardants were determined in eggs of marine and freshwater bird species from the province of British Columbia, Canada. Temporal trends in the Fraser River estuary, 1983-2002, were examined by analysis of eggs of great blue herons (Ardea herodias) and from the Strait of Georgia marine ecosystem, 1979-2002, in eggs of double-crested cormorants (Phalacrocorax auritus). Results were compared to those from eggs of the osprey (Pandion haliaetus) taken along the lower Fraser River and along the Columbia River near Castlegar, British Columbia, and of a pelagic seabird, the Leach's storm-petrel (Oceanodroma leucorhoa), collected at a colony on the Queen Charlotte Islands. Mean concentration of sigmaPBDE, 455 microg/kg w.w., were highest in heron eggs collected in 2002 from the Fraser estuary. Concentrations in eggs of cormorants and ospreys taken from sites of varying urban influence tended to be about half that value. Leach's storm petrel eggs had only trace amounts of sigmaPBDE (3.38 microg/kg), despite having similar concentrations of PCBs and organochlorine pesticides to the other species. PBDEs increased exponentially with a doubling time of 5.7 years in eggs of both herons and cormorants. Over this period of increasing PBDEs, major chlorinated hydrocarbons, such as PCBs and DDE, were stable or decreased. The PBDE pattern was relatively consistent in most years and sites, with BDEs 47 > 100 > 99 > 153 > 154 > 28 > 183. This was interpreted as evidence of technical pentaBDE formulations as primary sources of the contamination, with the octaBDE formulations as secondary. Higher resolution analysis of a subsample of the eggs revealed the presence of up to nine other congeners, including BDE209 (range: 0.9-1.8 microg/kg), indicating exposure and uptake of decaBDE sourced congeners in North American foodchains. At some locations, concentrations of pentabrominated congeners and mixtures in fish are approaching levels potentially toxic to fish-eating birds, based on rodent studies and calculations of dietary intake from fish data.  相似文献   

11.
In P.R. China, electronic waste (e-waste) from across the world is dismantled and discarded. Concentrations of polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) were measured in serum from residents of an e-waste dismantling region (Guiyu, South China), where 80% of families work in e-waste recycling, and compared to a matching cohort from a nearby region where the fishing industry dominates (Haojiang). Serum concentrations of PBDEs and OCPs, but not PCBs, were significantly different in the two regions: the median sigmaPBDE concentration was 3 times higher in Guiyu than Haojiang, whereas the opposite was true for dichloro-diphenyl-trichloroethane (DDT). PBDEs typically accounted for 46% of the total organohalogen chemicals in samples from Guiyu, but 8.7% in Haojiang. The median BDE-209 concentration in Guiyu was 50-200 times higher than previously reported in occupationally exposed populations. The highest BDE-209 concentration was 3100 ng/g lipid, the highest yet reported in humans. Serum PBDE concentrations did not correlate with PCBs or OCPs, whereas PCBs and OCPs showed positive correlations, suggesting that sources of PBDEs to humans are different from PCBs and OCPs. The levels of PBDEs in individuals from Haojiang are possibly related to the recycling activity at Guiyu, through atmospheric transport.  相似文献   

12.
Polybrominated diphenyl ethers in house dust and clothes dryer lint   总被引:2,自引:0,他引:2  
Few studies have measured the flame retardants polybrominated diphenyl ethers (PBDEs) in the indoor environment. Here, we report measurements of PBDEs in house dust samples collected from the Washington, D.C. metropolitan area in the United States. Dust samples were analyzed for 22 individual PBDE congeners and our results found PBDEs present in every sample. Concentrations of total PBDEs ranged from 780 ng/g dry mass to 30 100 ng/g dry mass. The dominant congeners observed in the dust samples were congeners associated with the pentaBDE and decaBDE commercial mixtures. Ancillary data were collected on the homes and examined for any correlations with total PBDE concentrations. No correlations were observed with year of house construction, type of flooring (i.e., hardwood vs carpet) or the number of television sets or personal computers in the home. However, a significant inverse correlation (p < 0.05) was observed between the area of the home and the contribution of BDE 209 to the total PBDE concentration in dust. Using estimates of inadvertent dust ingestion (0.02-0.2 g/day) by young children (ages 1-4), we estimate ingestion of total PBDEs to range from 120 to 6000 ng/day. Clothes dryer lint was also sampled and analyzed for PBDEs from five of the homes and were present in all five samples ranging from 480 to 3080 ng/g dry mass. This study demonstrates that PBDEs are prevalent at relatively high concentrations within homes where people, and particularly young children, may be susceptible to exposure.  相似文献   

13.
The objective of this study was to determine the concentrations and compositions of polybrominated biphenyls (PBBs), polybrominated dibenzo-p-dioxins (PBDDs), and polybrominated dibenzofurans (PBDFs) as contaminants in the commercial polybrominated diphenyl ether (PBDE) mixtures DE-71, DE-79, and DE-83 and to ascertain the lot-to-lot variations in the proportions of these contaminants. Commercial PBDE mixtures tested in the present study contained both PBBs and PBDFs, as impurities, at concentrations in the range of several tens to several thousands of nanograms per gram. Concentrations of total PBDFs were greater than those of total PBBs in DE-79 and DE-83 mixtures. PBDDs were not detected at levels above the limit of detection. Profiles of PBB and PBDF congeners varied with the degree of bromination of the commercial PBDE mixtures (i.e., more highly brominated mixtures of PBDEs contained heavily brominated homologues of PBBs and PBDFs). On the basis of the production/ usage of commercial PBDE mixtures in 2001, potential global annual emissions of PBBs and PBDFs were calculated to be 40 and 2300 kg, respectively. Results of our study suggestthat PBDFs can also be formed during the production of commercial PBDE mixtures, in addition to their formation during pyrolysis of brominated flame retardants.  相似文献   

14.
Despite the growing public interest in polybrominated diphenyl ethers (PBDEs), there are relatively few studies in the published literature which characterize and quantify human intake of these compounds. In this study, PBDE concentrations were measured in southern Mississippi catfish to determine background levels, daily intake, and risk associated with the consumption of these chemicals from a primary food source for residents in this region of the United States. A total of 33 wild catfish samples were collected from five sites, and 28 farm-raised catfish samples were purchased, all of which were from locations in southern Mississippi. All samples were analyzed for 43 PBDEs (mono- through deca-congeners) using high-resolution gas chromatography-mass spectrometry. Both PBDE concentrations (sigmaPBDE ranged from 0.3 to 23.3 ng/g wet weight) and congener profiles varied by fish type and location; however, BDE congeners 47, 99, 100, 153, and 154 were the dominant contributors in all samples. The estimated daily intake of PBDEs associated with consumption of the catfish ranged from 0.03 to 1.80 ng/kg-day. Evaluation of the cancer risk for BDE 209 and the noncancer hazard for BDE congeners 47, 99, 153, and 209 indicated that health risks/hazards due to fish consumption in adults are substantially lower than risk levels generally considered to be at the U.S. EPA minimum concern level.  相似文献   

15.
Polybrominated diphenyl ethers (PBDEs) are a class of flame retardants historically used in textiles, furniture, and electronic products. Recent studies have documented widespread PBDE exposure to humans, with higher levels measured in children than adults. We analyzed 10 tri- to hepta-BDE congener levels in blood collected from 7-year old Mexican-American children living in an agriculture community in California (n = 272). The most frequently detected PBDE congeners in child serum were BDE-47, -99, -100, and -153, all of which were measured in >99% of the children. We used multiple linear regression models to examine associations between child total PBDE levels (ng/g lipid) and determinants of exposure. Factors positively associated with higher PBDE levels in the children were total PBDE levels in maternal serum during pregnancy, duration of exclusive breastfeeding, and having no safe places to play in their neighborhood. Child BMI was inversely associated with serum PBDE levels (regression p-values <0.05). Our findings confirm that exposure to the penta-BDE mixture is ongoing, and that Mexican-American children living in California may be experiencing higher PBDE exposure from their environment compared to children sampled from the general U.S. population. Additional research is needed to assess the health impacts of these exposures.  相似文献   

16.
In recent years, polybrominated diphenyl ethers (PBDEs) have been detected at increasing levels in the environment due to their widespread use as flame retardants. PBDEs can affect thyroid hormone homeostasis and the cholinergic neurotransmitter system. In this study, several PBDE congeners were detected in whole brain samples and neuronal cells of herring gulls (Larus argentatus). A herring gull neuronal cell culture method was used to determine the effects of PBDEs on cytotoxicity and mRNA expression. Real-time RT-PCR assays were developed for genes associated with the thyroid hormone pathway (thyroid hormone receptors [TR alpha and beta], transthyretin [TTR]), and the cholinergic system (neuronal nicotinic acetylcholine receptor alpha-7 [nAChR alpha-7]). Administration of T3 resulted in a significant up-regulation of the two TRs and a significant down-regulation of TTR. TTR was also down-regulated by the commercial penta-BDE mixture, DE-71. In contrast, neither DE-71, nor BDE-47, -99, or -100 altered the mRNA levels of the TRs or nAChR alpha-7. The in vitro approach was a relevant model system for assessing the effects of PBDEs on cytotoxicity and mRNA expression. Herring gull neuronal cells were responsive to both T3 and PBDEs although, receptors associated with two predicted mechanisms of PBDE action were not effective molecular biomarkers of exposure.  相似文献   

17.
Polybrominated diphenyl ethers (PBDEs) were determined in adipose tissue of adult and subadult female polar bears sampled between 1999 and 2002 from sub-populations in Arctic Canada, eastern Greenland, and Svalbard, and in males and females collected from 1994 to 2002 in northwestern Alaska. Only 4 congeners (BDE47, 99, 100, and 153) were consistently identified in all samples. BDE47 was the major PBDE congener representing from 65% to 82% of the sum (sigma) PBDEs. Age was not a significant covariate for individual PBDEs or sigmaPBDE. Higher proportions of BDE 99, 100, and 153 were generally found in samples from the Canadian Arctic than from Svalbard or the Bering-Chukchi Sea area of Alaska. Geometric mean sigmaPBDE concentrations were highest for female polar bear fat samples collected from Svalbard (50 ng/g lipid weight (lw)) and East Greenland (70 ng/g lw). Significantly lower sigmaPBDE concentrations were found in fat of bears from Canada and Alaska (means ranging from 7.6 to 22 ng/g lw).  相似文献   

18.
The present study is primarily designed to examine the role played by dietary sources on polybrominated diphenyl ethers (PBDE) congener profiles in waterbirds collected in an e-waste recycling region in South China. Some emerging halogenated flame retardants (HFRs), such as dechlorane plus (DP), 2,3,4,5,6-pentabromoethyl benzene (PBEB), pentabromotoluene (PBT), and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), were also quantified. Stable isotopes (δ(15)N and δ(13)C) were analyzed to assess the trophic levels and dietary sources of the birds. PBDEs were found to be the predominant HFRs, followed by DP, PBT, PBEB, and BTBPE. The birds in which BDE209 was predominant have differential δ(13)C and δ(15)N signatures compared with other birds, suggesting that dietary source is one of the important factors in determining the PBDE congener profile in birds. The levels of ΣPBDEs, PBEB, and PBT were significantly correlated with the trophic level (δ(15)N) for avian species which are located in a food chain, indicating the biomagnification potential of these compounds. No correlation was found between DP concentrations and trophic level of the birds. There is a significantly negative correlation between the fraction of anti-DP and δ(15)N, suggesting that the metabolic capability of DP in birds increases with the trophic level of the birds.  相似文献   

19.
Novel classes and congeners of contaminant residues that are structurally analogous to polybrominated diphenyl ether (PBDE) flame retardants were assessed in the plasma of seven benthic- and six pelagic-feeding fish species from the highly contaminated Detroit River corridor, namely, hydroxylated-PBDEs (OH-PBDEs), methoxylated-PBDEs (MeO-PBDEs), and the antimicrobial OH-trichlorodiphenyl ether, triclosan, and its methylated (MeO) triclosan analogue. In all samples sigmaPBDE concentrations were comprised mainly of BDE47, BDE99, and BDE100 (>85%) and ranged from 155 pg/g wet weight (ww) to 21 069 pg/g ww. Of the 14 OH-PBDE congeners assessed, as many as 10 congeners were identified, although profiles were generally dominated by 6-OH-BDE47 with lesser amounts of 2'-OH-BDE68, 4'-OH-BDE49, and 4-OH-BDE42. sigmaOH-PBDE concentrations ranged from 2.7 to 198 pg/g ww, with sigmaPBDE to sigmaOH-PBDE concentration ratios ranging from 0.0005 to 0.02. OH-PBDEs are likely derived in these freshwater species as metabolites of precursor PBDEs and are subsequently retained in the blood, for example, 6-OH-BDE47, 4'-OH-BDE49, and 4-OH-BDE42 could be derived from BDE47. Portions of concentrations of the OH-PBDEs may also be of alternate origins and are accumulated and retained in these fish. In all samples, the 14 MeO-PBDEs monitored were below detection (<0.01 pg/g ww). Anthropogenic triclosan concentrations ranged from 750 to >10 000 pg/g ww and is clearly a bioaccumulative halogenated phenolic compound in these fish. MeO-triclosan concentrations were considerably lower. In addition to emerging classes of brominated contaminant such as PBDEs, whether of metabolic or anthropogenic origin, fish collected from the Detroit River are exposed to a complex profile of PBDE-like organohalogens.  相似文献   

20.
Air samples from automobile cabins were collected and analyzed for polybrominated diphenyl ethers (PBDEs), polybrominated dibenzofurans (PBDFs), and polybrominated dibenzo-p-dioxins (PBDDs). The concentration of total PBDEs (sigmaPBDE; sum of 19 congeners) varied from 0.4 to 2644 pg m(-3), with a median of 201 pg m(-3), while BDE 47, 99, and 209 collectively accounted for 70 +/- 30% of sigmaPBDE concentrations. Multiple linear regression analysis revealed that sigmaPBDE concentration was significantly influenced by vehicle's age and interior temperature. More specifically, sigmaPBDE decreased over time and increased with the rise of temperature. The daily inhalation intake of PBDEs during commuting was estimated to range from 0.5 to 2909 pg day(-1) (median 221 pg day(-1)) and contributed 29% of the overall daily exposure to PBDEs via inhalation. When excluding BDE 209, a lower contribution was calculated for this source (18%), but this was still comparable with residential exposure (22%). The levels of PBDD/Fs were generally below the limits of detection and only in one case were hepta-BDFs positively detected at a concentration of 61 pg m(-3). This study demonstrates that car interiors, especially when new, contain high levels of airborne PBDEs and represent a potential route of human exposure via inhalation.  相似文献   

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