Dechlorane plus levels in sediment of the lower Great Lakes

A recently discovered chlorinated flame retardant, Dechlorane Plus (DP), was reported in air and a sediment core within the North American Great Lakes region. To further reveal the fate of DP in the Great Lakes, 40 surficial sediments from Lakes Erie and Ontario and two additional cores were analyzed using newly available analytical grade DP isomer solutions. The maximum total concentration in Lake Ontario was over 60-fold higher than Lake Erie, 586 ng/g and 8.62 ng/g, respectively. Additionally, analysis of archived suspended sediments collected from the Niagara River (1980-2002) showed a declining total DP concentration of 89 ng/g to 7.0 ng/g, suggesting a possible decrease in production orthe reduction of free DP released into the environment during manufacturing. The average syn-DP fractional abundance (f(syn)) in our study was less than the commercial DP composition indicating a stereoselective enrichment of anti-DP in the environment Mean fyn profiles were uniquely similar to both Lake Ontario and the Niagara River in comparison to Lake Erie. During the course of our analysis we noticed an increasing f(syn) value in the calibration standard which became exacerbated as the liner got dirtier and suggested the prospect of DP degradation. Followup studies indicated these compounds were dechlorinated DP species produced on the injection liner. Using a clean injection liner, these degradates were also detected in sediments from the Niagara River and Lake Ontario;tentatively identified as [-Cl+H] and [-2Cl+2H] by high resolution mass spectrometry. The observed similarity of f(syn) profiles between Lake Ontario and Niagara River and the detection of the degradates only in their locations, suggest to us that the river is a major source to Lake Ontario's DP burden. To our knowledge, this is the first report of DP degradates in the environment.     

Dechlorane plus in the atmosphere and precipitation near the Great Lakes

Air (vapor and particle) and precipitation samples were collected at five sites (two urban, one rural, and two remote) on the shores of the Great Lakes from January 1, 2005 to December 31, 2009 as a part of the Integrated Atmospheric Deposition Network (IADN). The concentrations of the syn and anti isomers of Dechlorane Plus (DP), a highly chlorinated flame retardant, were measured in these samples. The highest concentrations of these compounds were generally observed at the rural site at Sturgeon Point, New York, which is located near DP's manufacturing facility in Niagara Falls, New York, and at the urban site at Cleveland, Ohio. A multiple linear regression model was applied to the concentrations of these compounds in the vapor phase, particle phase, precipitation, and for the three phases combined. This regression resulted in an overall (three phases combined) doubling time for the anti-DP isomer of 9.5 ± 3.6 years, but for the syn- and total DP (syn + anti) concentrations, the overall regression was not statistically significant. These results suggest that there has been no significant change in the atmospheric concentrations of these compounds over the 2005-2009 time period. The effect of distance from the source in Niagara Falls was highly significant; for example, doubling the distance from Niagara Falls decreased the DP concentrations by about 30%. The effect of the number of people living and working within a 25-km radius of the sampling site (population density) was also highly significant but small; for example if this population doubled or halved, then the atmospheric DP concentrations would increase or decrease by only a few percent.     

Dechlorane plus and other flame retardants in a sediment core from Lake Ontario

Our previous research on atmospheric samples suggested that Lake Ontario might receive significant amounts of Dechlorane Plus (DP), a highly chlorinated flame retardant, from the atmosphere and from inputs from DP's manufacturing facility in Niagara Falls, New York. To confirm this suspicion, a sediment core from the central basin of Lake Ontario was analyzed for the two isomers of DP, for polybrominated diphenyl ethers (PBDEs), and for 1,2-bis-(2,4,6-tribromophenoxy)ethane (TBE). The results showed that the concentration of DP in sediment increased rapidly starting in the mid-1970s and reached its peak concentration (310 ng g(-1) dry weight) in the mid-1990s. The peak flux and total inventory of DP were estimated to be 9.3 ng cm(-2) yr(-1) and 120 ng cm(-2), respectively. These values suggest that the total burden of DP in Lake Ontario is approximately 20 tons and that the maximum load rate was approximately 2 tons per year. The highest concentrations of PBDEs and TBE were found in the surficial sediment, with average concentrations of 2.8, 14, and 6.7 ng g(-1) d.w. for PBDE(3-7) (tri-through hepta-BDEs), BDE-209, and TBE, respectively. The surface fluxes were 0.08, 0.43, and 0.20 ng cm(-2) yr(-1), and the inventories were 0.87, 3.9, and 1.8 ng cm(-2) for PBDE3-7, BDE-209, and TBE, respectively. The concentration of DP in Lake Ontario sediment exceeds that of the brominated flame retardants combined.     

Dechlorane plus and other flame retardants in tree bark from the northeastern United States

Previous work has shown that certain parts of the Great Lakes region are polluted with Dechlorane Plus (DP), a highly chlorinated flame retardant that was used as a replacement for Dechlorane/Mirex. It was suspected that a source of DP to the environment might be its manufacturing facility located in the city of Niagara Falls, New York. To confirm this source location and to determine DP's spatial distribution, 26 tree bark samples were collected in triplicate from the northeastern United States, and the concentrations of DP and several brominated flame retardants (BFRs) were measured. Most concentrations of DP in tree bark were found to be much higher than those of the BFRs. The highest DP concentrations were >100 ng g(-1) bark in the city of Niagara Falls, dropping rapidly with distance from the potential source. A simple one-dimensional, Gaussian diffusion model was used to explain the spatial distribution of DP and to locate the source. The calculated source location was <7 km away from the DP manufacturing plant in Niagara Falls, New York.     

Emerging brominated flame retardants in the sediment of the Great Lakes

The concentrations of 13 currently used brominated flame retardants (BFRs) were analyzed in 16 sediment cores collected from the North American Great Lakes. Among them, 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), decabromodiphenyl ethane (DBDPE), hexabromocyclododecane (HBCD), 1,2-dibromo-4-(1,2-dibromoethyl)cyclohexane (TBECH), and hexachlorocyclopentadienyl dibromocyclooctane (HCDBCO) were more frequently detected than others. In general, these emerging BFRs have much lower concentrations than polybromodiphenyl ethers (PBDEs) and dechloranes. Inventories of the five BFRs named above, given on a logarithm basis, were found to decrease linearly with the increasing latitude of the sampling locations, but with weaker statistics than those previously reported for the dechloranes. Logarithm of surface fluxes, on the other hand, was found to be a better parameter in correlating with the longitude. With regard to time trends, the exponential increases in concentrations of these BFRs, particularly DBDPE and BTBPE, in recent years are particularly disturbing. The sediment concentration of DBDPE doubles every 3-5 years in Lake Michigan, and approximately every 7 years in Lake Ontario. The corresponding doubling times for BTBPE are about 5 and 7 years in Lakes Ontario and Michigan, respectively, although declines or leveling off were observed in the top sediment layers in Lake Ontario. In contrast to PCBs, PBDEs, and most dechloranes, the correlations between the surface concentration of emerging BFRs and the latitude or longitude of the sampling sites were not strengthened by normalization of the concentration based on the organic matter content of the sediment.     

Dechloranes 602, 603, 604, Dechlorane Plus, and Chlordene Plus, a newly detected analogue, in tributary sediments of the Laurentian Great Lakes

A chlorinated compound (Chlordene Plus, CP), structurally related to Dechloranes (Dec) 602, 603, 604, and Dechlorane Plus (DP), was identified, and concentrations and spatial trends of Dec 602, 603, 604, CP, and DP in tributary sediments of the Laurentian Great Lakes are reported. The dechloranes were widely detected with their concentrations varying considerably across the Great Lakes basin. Spatial trends of Dec 602, 604, and DP in Canadian tributary sediments were similar to that of BDE 209, which suggested these flame retardant chemicals in tributaries were associated with industrial and urban areas. The highest concentrations of Dec 602, 604, and DP observed in tributaries of the Niagara River confirmed that past or ongoing manufacturing of these compounds at plants along the river were important sources to Lake Ontario. Dec 603 was detected in technical products of aldrin and dieldrin, and its spatial trend was consistent with historic pesticide usage. Similarly, CP was detected in technical products of chlordene and chlordane, and it was found in higher concentrations in sediments near urban areas, possibly related to past chlordane use in home termite control.     

Dechlorane plus and related compounds in the environment: a review

Dechlorane Plus (DP) is a high production volume, chlorinated flame retardant. Despite its long production history, it was only recently found in the environment. The first "sightings" of DP were in the North American Great Lakes, but subsequent work has indicated that DP is a global contaminant. For example, DP has recently been detected along a pole-to-pole transect of the Atlantic Ocean. Although it was initially thought that DP was produced only in North America, another DP production plant has recently been identified in China. During the course of characterizing DP in the environment, other "DP-like" compounds were identified. These DP analogs, some created from impurities contained in the starting materials during DP's synthesis, have also been detected globally. Screening-level modeling data are in general agreement with available environmental measurements, suggesting that DP and it analogs may be persistent, bioaccumulative, and subject to long-range transport and that these chemicals may be candidates for Annex D evaluation under the United Nations Stockholm Convention on Persistent Organic Pollutants. However, more research is required to better quantify the emissions, exposures, and toxicological effects of DP and its analogs in the environment. In particular, there is a need to obtain more monitoring, bioaccumulation, degradation rate, and toxicity information.     

新型涤纶阻燃剂在机车阻燃面料的应用及探讨

阐述了汽车或机车装饰面料对阻燃效果的要求,采用新型涤纶阻燃剂,设计了浸轧-涂层和浸轧-水洗-涂层阻燃整理工艺,测试并比较了两种工艺整理后试样与进口阻燃面料的阻燃效果,将试样分别置于常温水中浸渍24 h、自然晾干后的阻燃效果,以及阻燃整理后面料的色牢度及pH值情况。得出两种工艺整理后的布样基本达到进口布样的阻燃要求,色牢度和布面pH值相近。     

新型氮-磷阻燃剂制备及其对棉织物的阻燃性能

为同步实现纺织品高分子材料高效、低毒的阻燃性能,充分利用氮-磷之间的协同效应,以六氯环三磷腈(HCPP)和季戊四醇磷酸酯(PEPA)为原料,制备了一类新型氮-磷无卤阻燃剂(HCPPA),其对棉织物的阻燃性能通过氧指数仪和垂直燃烧仪进行测试。结果表明:当阻燃剂添加量为28%时,HCPPA的极限氧指数高达35%,阴燃时间为0.3 s,经HCPPA处理的棉织物水洗15次后极限氧指数仍然高达32.5%,显示出优异的阻燃性能和良好的耐水洗性;与六苯氧基环三磷腈(HPCTP)和季戊四醇磷酸酯(PEPA)相比,HCPPA具有更优异的阻燃性能,有望在纺织、塑料和涂料等产品的阻燃工业中具有更好的应用前景。     

Temporal trends and spatial distributions of brominated flame retardants in archived fishes from the Great Lakes

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.     

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.     

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.     

Microbial O-methylation of the flame retardant tetrabromobisphenol-A

We demonstrated the O-methylation of tetrabromobisphenol-A (TBBPA) [4,4'-isopropylidenebis (2,6-dibromophenol)] to its mono- and dimethyl ether derivatives by microorganisms present in different sediments. A most probable number assay of a marsh sediment suggested that up to 10% of the total aerobic heterotrophs may be capable of O-methylation. Although TBBPA dimethyl ether is not produced in industry, it has been detected in terrestrial and aquatic sediments. Our study supports the hypothesis that TBBPA dimethyl ether is a product of microbial O-methylation. The O-methylation of TBBPA, as well as its analog, tetrachlorobisphenol-A (TCBPA), was also demonstrated in cultures of two chlorophenol-metabolizing bacteria, Mycobacterium fortuitum CG-2 and Mycobacterium chlorophenolicum PCP-1. These strains also mediated the O-methylation of 2,6-dibromophenol and 2,6-dichlorophenol, analogs of TBBPA and TCBPA, to their corresponding anisoles, but 2,6-fluorophenol was not transformed. Due to the addition of hydrophobic methyl groups, O-methylated derivatives are more lipophilic, increasing the probability of bioaccumulation in the food chain. Future research regarding the toxicological effects of the O-methylated derivatives of TBBPA is recommended and will further elucidate potential risks to environmental and human health.     

棉织物用磷-氮系阻燃剂的阻燃工艺探讨

以磷-氮系阻燃剂为工作液研究棉织物阻燃工艺,对棉织物耐久阻燃工艺流程、工艺条件、阻燃效果等进行了介绍。根据阻燃协同效应的理论,采用郑州大学化学系研制的无毒、低烟环保、水溶性极好的Fr～21磷-tK（P-N）系新型阻燃剂进行处理,具有优良的阻燃效果,并且不损伤织物的强力和手感。     

阻燃纤维素气凝胶研究进展

为提高纤维素气凝胶的阻燃性,拓宽其应用领域,首先介绍了纤维素气凝胶的分类及其制备方法;然后综述了当前应用较为广泛的无机阻燃剂、有机阻燃剂和有机/无机复合阻燃剂等阻燃改性纤维素气凝胶的研究进展,并对比分析了各类阻燃剂的优缺点.其中,有机/无机复合阻燃剂兼具无机和有机阻燃剂的优点,表现出高效的阻燃效率,但也存在与纤维素基体...