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1.
ABSTRACT

Diesel exhaust (DE) characteristic of pre-1988 engines is classified as a “probable” human carcinogen (Group 2A) by the International Agency for Research on Cancer (IARC), and the U.S. Environmental Protection Agency has classified DE as “likely to be carcinogenic to humans.” These classifications were based on the large body of health effect studies conducted on DE over the past 30 or so years. However, increasingly stringent U.S. emissions standards (1988–2010) for particulate matter (PM) and nitrogen oxides (NOx) in diesel exhaust have helped stimulate major technological advances in diesel engine technology and diesel fuel/lubricant composition, resulting in the emergence of what has been termed New Technology Diesel Exhaust, or NTDE. NTDE is defined as DE from post-2006 and older retrofit diesel engines that incorporate a variety of technological advancements, including electronic controls, ultra-low-sulfur diesel fuel, oxidation catalysts, and wall-flow diesel particulate filters (DPFs). As discussed in a prior review (T. W. Hesterberg et al.; Environ. Sci. Technol. 2008, 42, 6437-6445), numerous emissions characterization studies have demonstrated marked differences in regulated and unregulated emissions between NTDE and “traditional diesel exhaust” (TDE) from pre-1988 diesel engines. Now there exist even more data demonstrating significant chemical and physical distinctions between the diesel exhaust particulate (DEP) in NTDE versus DEP from pre-2007 diesel technology, and its greater resemblance to particulate emissions from compressed natural gas (CNG) or gasoline engines. Furthermore, preliminary toxicological data suggest that the changes to the physical and chemical composition of NTDE lead to differences in biological responses between NTDE versus TDE exposure. Ongoing studies are expected to address some of the remaining data gaps in the understanding of possible NTDE health effects, but there is now sufficient evidence to conclude that health effects studies of pre-2007 DE likely have little relevance in assessing the potential health risks of NTDE exposures.

IMPLICATIONS Based on the distinct physical and chemical properties of New Technology Diesel Exhaust (NTDE), it has become clear that findings from the health effects studies conducted on traditional DE (TDE) over the last 30 years have little relevance to NTDE, which is more similar to the exhaust from compressed natural gas (CNG) or gasoline engine emissions than to traditional TDE. Once sufficient health effects data are available for NTDE, it will thus be necessary to conduct new hazard and risk assessments for NTDE that are independent of the DE toxicological database acquired on emissions from pre–2007 diesel technology.  相似文献   

2.
Beta blockers are widely used pharmaceuticals that have been detected in the environment. Interactions between beta blockers and dissolved organic matter (DOM) may mutually alter their environmental behaviors. To assess this potential, propranolol (PRO) was used as a model beta blocker to quantify the complexation with DOM from different sources using the fluorescence quenching titration method. The sources of studied DOM samples were identified by excitation–emission matrix spectroscopy (EEMs) combined with fluorescence regional integration analysis. The results show that PRO intrinsic fluorescence was statically quenched by DOM addition. The resulting binding constants (log K oc) ranged from 3.90 to 5.20, with the surface-water-filtered DOM samples claiming the lower log K oc and HA having the highest log K oc. Log K oc is negatively correlated with the fluorescence index, biological index, and the percent fluorescence response (P i,n) of protein-like region (P I,n) and the P i,n of microbial byproduct-like region (P II,n) of DOM EEMs, while it is correlated positively with humification index and the P i,n of UVC humic-like region (P III,n). These results indicate that DOM samples from allochthonous materials rich in aromatic and humic-like components would strongly bind PRO in aquatic systems, and autochthonous DOM containing high protein-like components would bind PRO more weakly.  相似文献   

3.
上海市机动车尾气VOCs组成及其化学反应活性   总被引:9,自引:0,他引:9  
采用钢罐采样-气相色谱/质谱法,采集并分析了上海市主要交通干道和隧道废气样品中挥发性有机物(VOCs)的污染水平。分析结果表明,交通干道和隧道废气样品的总挥发性有机污染物(TVOC)质量浓度分别为(227.1±40.9)、(2209.9±1228.0)μg/m3;隧道废气样品中的TVOC浓度是交通干道平均浓度的4.3~15.2倍;交通干道废气样品中VOCs主要组分与隧道废气样品中VOCs主要组分非常类似,说明交通干道废气样品中VOCs主要来源于机动车尾气排放。交通干道废气样品中TVOC的.OH消耗速率为(17.21±4.49)s-1,延安东路隧道和打浦路隧道废气样品中TVOC的.OH消耗速率分别为(300.37±120.78)、(138.09±25.30)s-1,烯烃对TVOC的.OH消耗速率贡献最大,其对废气化学反应活性贡献率在70%以上。交通干道和隧道废气样品中关键活性组分是C2~C5的烯烃组分,这些组分也是机动车尾气中的特征污染物,因此可以判断机动车尾气是上海市大气化学反应活性的最大贡献者。  相似文献   

4.
The observed high-level burdens of organohalogens among the residents of the Faroe Islands, needs to be explained. Long-finned pilot whale (Globicephala melas) blubber and meat are known sources of environmental exposure. The present study focus on the organohalogen contamination of the fulmar (Fulmarus glacialis). The compounds quantified in fulmar muscle, fat, and egg are PCBs, DDTs, hexachlorobenzene (HCB), and polybrominated diphenyl ethers (PBDEs). The dominating pollutants are the 4,4'-DDT metabolite 4,4'-DDE and the two PCB congeners, CB-153 and CB-180, which are present in geometric mean concentrations of 7100, 4700 and 2500 ng/g lipid weight (l.w.), respectively, in adult fulmar muscle. 4,4'-DDT and HCB concentrations are approximately 250 ng/gl.w., each. Concentrations in the eggs are about 50% of the fulmar muscle levels, due to differences in lipid amounts, 4% in muscle and 10% in the eggs, the exposure contribution on a fresh weight basis is almost the same. As a result, both the egg and the adult fulmar muscle may lead to a significant exposure risk, if consumed by humans. BDE-153, the most abundant PBDE congener in fulmar muscle, with a geometric mean concentration of 6.5 ng/gl.w., is much lower than the individual PCB congeners and 4,4'-DDE concentrations. In the adult fulmar muscle, the relative PBDE congener pattern is different from that previously observed in biota, with BDE-153 and BDE-154 as the dominating congeners, rather than BDE-47. In contrast, BDE-47 is the most abundant congener in juvenile muscle and subcutaneous fat. The summation operatorPBDE concentrations are almost the same in egg, muscle (adult and juvenile) and subcutaneous fat (juvenile). For the polybrominated biphenyl (BB-153) the concentrations are considerably higher in the adult bird and egg than in the juvenile bird; this is also seen for the PCB and 4,4'-DDE concentrations. PCB concentrations found in fulmar egg and muscle are in the same range as seen in the pilot whale, i.e. 590-5700 ng/gl.w. for CB-153. Hence humans are also exposed to PCBs at a reasonable degree via intake of fulmar and/or fulmar egg and not only via pilot whale blubber.  相似文献   

5.
In this study, contamination levels were determined for polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and perfluorinated alkylated substances (PFASs) in traditional Greenland seafood items, such as raw and smoked fish fillet (salmon and halibut), whale and seal meat and narwhal mattak (skin and blubber). The daily intake of PCBs, PBDEs and PFASs through traditional seafood items in Greenland was assessed. Based on the presented levels of contaminants, in combination with earlier food intake studies, suggests that the daily exposure was below the tolerable daily intake threshold for all compounds. BDE-47 was the only PBDE-congener detected in all food items, except in smoked halibut. The levels of BDE-47 varied from < LOD in smoked halibut up to 18 ng/g lw in narwhal mattak and 21 ng/g lw in whale beef. ∑PCB were lowest in smoked halibut (37 ng/g lw) and highest in narwhal mattak with 1,146 ng/g lw. Perfluorooctane sulfonate (PFOS) was the most common of the PFASs. However, ΣPFASs were below detection limits in most fish fillet samples, and varied from 2.9 ng/g ww in whale beef to 13.5 ng/g ww in seal beef. The present study shows that the exclusion from the diet of local food items such as intestines and blubber have a strong positive effect for the reduction of POPs levels in food, without a reducing the health benefits of traditional food intake considerably.  相似文献   

6.
Data on distribution, concentration and trends of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) is scarce in biota from the sub-Arctic region of the Atlantic. The present study is an investigation on PBDE and HBCD concentrations in eggs from seven marine bird species from Iceland, i.e. common eider (Somateria mollissima), arctic tern (Sterna paradisaea), guillemot (Uria aalge), fulmar (Fulmarus glacialis), lesser black-backed gull (Larus fuscus), great black-backed gull (Larus marinus) and great skua (Stercorarius skua). Concentrations of sum PBDEs ranged from 44 ng g−1 fat in eider eggs to 2400 ng g−1 fat in great skua eggs. The contribution of different PBDE congeners to the sum concentration differed between species. Concentration of HBCDs (sum of α−,β and γ−HBCD) ranged from 1.3 ng g−1 fat in arctic tern eggs to 41 ng g−1 fat in great black-backed gull. PCA on PBDE and HBCD shows different trends between the two BFR groups, further indicating different sources/usage. Investigations on any potential health or population effects of environmental pollutants on the great skua are advised since both the PBDE and HBCD concentrations are high.  相似文献   

7.
The present study addresses the key issue of linking the chemical speciation to the uptake of priority pollutants Cd(II) and Pb(II) in the wastewater treatment plant effluents, with emphasis on the role of the colloidal organic matter (EfOM). Binding of Cd(II) and Pb(II) by EfOM was examined by an ion exchange technique and flow field-flow fractionation coupled to inductively coupled plasma mass spectrometry in parallel to bioassays with green microalga Chlorella kesslerii in ultrafiltrate (<1 kDa) and colloidal isolates (1 kDa to 0.45 μm). The uptake of Cd by C. kesslerii was consistent with the speciation analysis and measured free metal ion concentrations, while Pb uptake was much greater than that expected from the speciation measurement. Better understanding of the differences in the effects of the EfOM on Cd(II) and Pb(II) uptake required to take into account the size dependence of metal binding by EfOM.  相似文献   

8.
A major wintertime episode occurred 13–17 February 1983 in northeastern NJ. The spatial extent was defined by the meteorological conditions and the levels of indicator pollutants such as CoH's, SO2 and CO. Data from the Airborne Toxic Elements and Organic Species (ATEOS) sites (Newark, Elizabeth, Camden and Ringwood) were examined to determine if any were located in the affected area. The chemical composition of the Inhalable Particulate Matter (IPM), d50 = 15 μm, for both inorganic and organic species are described and differences from mean composition analyzed. Comparable data were heretofore unavailable for any winter episode occurring in the NY-NJ metropolitan area since 1971. Using information available from the 1953 and 1966 metropolitan area episodes, the magnitude of the February 1983 episode is classified, and clear-cut differences are noted.  相似文献   

9.
Selected water quality parameters and spectroscopic characteristics of dissolved organic matter (DOM) were examined during two different seasons for an artificial coastal lake (Shiwha Lake in South Korea), which are affected by seawater exchange due to the operation of a tidal power plant and external organic loadings from the upstream catchments. The coastal lake exhibited much lower concentrations of organic matter and nutrients than the upstream sources. The spectroscopic properties of the lake DOM were easily distinguished from those of the catchment sources as revealed by a lower absorption coefficient, lower degree of humification, and higher spectral slopes. The observed DOM properties suggest that the lake DOM may be dominated by smaller molecular size and less condensed structures. For the lake and the upper streams, higher absorption coefficients and fluorescence peak intensities but lower spectral slopes and humification index were found for the premonsoon versus the monsoon season. However, such seasonal differences were less pronounced for the industrial channels in the upper catchments. Three distinctive fluorophore groups including microbial humic-like, tryptophan-like, and terrestrial humic-like fluorescence were decomposed from the fluorescence excitation-emission matrix (EEM) of the DOM samples by parallel factor analysis (PARAFAC) modeling. The microbial humic-like component was the most abundant for the industrial channels, suggesting that the component may be associated with anthropogenic organic pollution. The terrestrial humic-like component was predominant for the upper streams, and its relative abundance was higher for the rainy season. Our principal component analysis (PCA) results demonstrated that exchange of seawater and seasonally variable input of allochthonous DOM plays important roles in determining the characteristics of DOM in the lake.  相似文献   

10.
Vetter W  Turek C  Marsh G  Gaus C 《Chemosphere》2008,73(4):580-586
Marine mammals from Queensland, Australia, are bioaccumulating elevated concentrations of a range of polybrominated natural products. In this study, we detected three new polybrominated dimethoxybiphenyls (PBDMBs) in the blubber of selected marine mammal samples which were identified as 2,6'-dimethoxy-3,3',5-tribromobiphenyl (2,6'-diMeO-BB 36), 2,2'-dimethoxy-3,3'-dibromobiphenyl (2,2'-diMeO-BB 36), and 6,6'-dimethoxy-3,3'-dibromobiphenyl (6,6'-diMeO-BB 11). These three PBDMBs are structurally related to the known natural product 2,2'-dimethoxy-3,3',5,5'-tetrabromobiphenyl (2,2'-diMeO-BB 80). In the first part of this study, 2,2'-diMeO-BB 80 was photochemically debrominated under UV irradiation. This resulted in seven of eight possible mono- to triBDMBs as debromination products. In the second part of this study, the structure of all PBDMBs debromination products was investigated. This was supported by synthesis of two diBDMB and one triBDMB via bromination and subsequent methylation of 2,2'-biphenyldiol. Structures of the remaining PBDMBs were tentatively assigned by considering the retention times, mass spectra and amounts formed during UV irradiation of 2,2'-diMeO-BB 80 . In the third part of this study, blubber of marine mammals from Australia was analysed for PBDMBs using gas chromatography in combination with electron ionization mass spectrometry (GC/EI-MS) in the selected ion monitoring mode. In these samples, 2,2'-diMeO-BB 80 was found at concentrations of 200-1800ngg(-1) lipid weight (lw). The latter represents the highest concentration reported for this compound in environmental samples. 6,6'-diMeO BB 11, 2,2'-diMeO BB 36, and 2,6'-diMeO BB 36 were present at approximately 7ngg(-1) lipids, or 0.43-1.5% of diMeO-BB 80. No further PBDMBs were detected in the samples. The di- and triBDMBs identified in marine mammal blubber have not been reported as natural products. They may represent either new natural products or transformation products of 2,2'-diMeO-BB 80.  相似文献   

11.
Environmental Science and Pollution Research - Colored dissolved organic matter (CDOM) is the main constituent of dissolved organic matter (DOM), also a key indicator of water quality conditions....  相似文献   

12.
Wintering oystercatchers (Haematopus ostralegus), charadriid shorebirds that chiefly feed on intertidal bivalves, suffered mass mortality in The Netherlands during severe frosts in 1986 and 1987. PCBs were analysed in liver and (partially) brain lipids of 96 birds to examine the influence of age (three categories), sex and wintering area (the Oosterschelde estuary versus the westernmost Wadden Sea) on levels, and the risk of intoxication due to starvation. Victims had lost nearly 40% of their normal winter weight. PCB-structures were similar in all age/sex categories, and in both areas. Sex did not affect total PCB-concentrations. First-winter Wadden birds had lower levels than subadults and adults, but an age-difference was absent in the Oosterschelde birds. Some juvenile outliers possibly originated from polluted breeding areas. Individual variation was considerable in most categories. Relevant ecological factors are discussed. Although a dam has considerably reduced the direct transport of PCBs into the Oosterschelde since 1969, contamination of local birds was hardly lower than in Wadden winterers. Influx of riverine PCBs into the Oosterschelde from coastal water may have been underrated. Starvation increased liver concentrations by a factor of 35; factors for the brain were 56 for juveniles and approximately 120 for older birds. Considering published lethal levels for other species, it is doubtful if PCBs contributed to this winter mortality.  相似文献   

13.
Pioneer plant species were observed growing on mined areas despite unfavourable conditions such as extreme pH, high salinity and phytotoxic levels of several elements. This study evaluated the contribution of pioneer species to the accumulation of soil organic matter (SOM). We collected 51 samples from 17 non-vegetated, natural and pioneer-vegetated sites in five highly saline mined areas in the Sierra de Cartagena (Spain). The composition of SOM was determined using total C, N and S elemental anlayzer, pyrolysis and solid state (13)C NMR spectroscopy. Results showed that pioneer species like Lygeum spartum had contributed approximately 11 kg SOM kg(-1) soil into the Balsa Rosa sites since 1991; it will take approximately 120 years of continuous growth for this plant to increase the SOM level comparable to natural site. In the Portman Bay area, Sarconia ramosissima and Phragmites australis can contribute SOM equivalent to present day SOM in natural sites in the next 30 years. Low quality SOM (C/N>20) deposited by pioneer plants was dominated by lignin-derived organic compounds such as phenols, guaiacols, syringols and aromatics while polyssacharides and alkyls were the major components in high quality SOM (C/N<20). The addition of SOM to mine wastes is similar to early stages of soil formation and with time, we expect the formation of well-developed Ah horizon on the surface of mine wastes. The presence of P. australis on several sites makes it a very good candidate for successful revegetation of hostile conditions found in many mined sites.  相似文献   

14.
在日处理200t进口流化床垃圾焚烧炉上,进行烟气喷水降温加上喷消石灰粉末脱除尾气中的酸性气体HCl和SO2的试验研究,HCl和SO2浓度由布袋除尘器出口的在线气体分析仪测得,结果表明HCl和SO2的去除率在Ca/Cl摩尔比等于9时分别为80%和20%,说明该法消石灰利用率较低,宜改为半干法脱除HCl和SO2酸性气体,以便降低吸收剂用量,提高运行的经济性.  相似文献   

15.
The risks to Indo-Pacific Humpback Dolphins and Finless Porpoises associated with polychlorinated biphenyls (PCBs) were assessed. Stomach contents from twelve stranded Humpback Dolphins and sixteen stranded Finless Porpoises were collected. Concentrations of total and isomer-specific PCBs in the stomach contents were determined using dual-column gas chromatography equipped with electron capture detectors (GC-ECD). Risks due to the PCBs were assessed in three scenarios, based on total PCBs (summation of 41 PCB congeners), total toxicity equivalency (TEQs) and PCB 118, using the toxicity reference values (TRVs) as the threshold effects benchmarks. The calculated risk quotients (RQs) showed that risks due to PCBs were generally low or negligible. Specifically, RQs from total TEQs and total PCBs for Finless Porpoises are below one, suggesting that PCBs should be a low risk for the Finless Porpoise in Hong Kong waters. However, the Humpback Dolphin has RQs larger than 1 for total TEQs and total PCBs when the 95th percentile data were used in the evaluation. This indicates that further investigation may be needed to examine more closely the potential impact of toxic contaminants in the habitat of the Humpback Dolphin.  相似文献   

16.
In 1996 forty-nine eels were caught from different locations along the rivers Oder (Hohenwutzen and Schwedt) and from 11 locations along the Havel river. They were analysed for PCDDs/PCDFs and the coplanar PCBs (PCB 77, PCB 126, PCB 169). Their contribution to 2,3,7,8-TCDD equivalents were estimated. In case of PCDDs/PCDFs these amounted between 1.8 and 15.2 pg/g fat (mean 6.1 pg/g; median 5.2 pg/g), in case of coplanar PCBs between 2.4 and 170.5 pg/g fat (mean 47.7 pg/g; median 36.1 pg/g). Lakes which are associated with but not directly located at the main stream of the river Havel contributed much less to contamination of the eels than the river segments situated in the more urbanised or industrialised sites along the main river.  相似文献   

17.
He MC  Sun Y  Li XR  Yang ZF 《Chemosphere》2006,65(3):365-374
Samples of water, suspended particulate matter (SPM) and sediment were collected from mid- and down-stream of the Yellow River. The distribution and concentration of 10 nitroaromatic compounds and polychlorinated biphenyls (PCBs) were extensively studied. The total concentration of 10 nitrobenzenes (SigmaNBs) varied from 0.269 to 9.052 microg l(-1) in water, from 2.916 to 164.4 microg kg(-1) dry weight in SPM, and from 0.954 to 14.72 microg kg(-1) dry weight in sediment. PCBs associated with the sediments, measured as the summed responses of Aroclor 1242, 1248, 1254, 1260 (in comparison to those of a standard 1:1:1:1 mixture), were found to be in the range of non-detectable to 5.98 microg kg(-1). In the samples collected, various PCB congeners showed similar distribution characteristics with congeners containing 3-5 chlorine atoms accounting for more than 96.4% of total PCB. In most of the samples, PCB concentrations occurred in the order: TetraCB > TriCB > PentaCB. Levels of SigmaNBs in the Yellow River were relatively low in comparison with values reported from other river and marine systems, and PCB levels were comparatively low. Relative to the PCBs, SigmaNBs showed significantly more difference among the various stations, presumably due to the influence of different pollution sources. No obvious correlation was observed between the pollutant concentrations and either the TOC or the grain size of the sediments.  相似文献   

18.
Persistent organochlorines, such as polychlorinated biphenyls including coplanar congeners and DDT compounds were measured in the liver of different species of mollusc cephalopods: broadtail squid (Illex coindetii), horned octopus (Eledone moschata) and spider octopus (Octopus salutii) collected in two different areas of the Adriatic Sea (central and southern Adriatic Sea). The concentration of PCBs exceeded DDT ones in horned octopus (PCBs: 617.0 ngg(-1) lipid weight, DDTs: 188.0 ngg(-1) lipid weight) and in spider octopus (PCBs: 590.0 ngg(-1) lipid weight, DDTs: 293.0 ngg(-1) lipid weight), while in broadtail squid PCB load (748.0 ngg(-1) lipid weight) was similar to those of DDTs (514.5 ngg(-1) lipid weight). No significant difference in PCB levels was observed among species, while DDT concentrations were higher in broadtail squid than in horned octopus and spider octopus. DDTs composition showed slight differences in relation to species, thought p,p'-DDE was the predominant compound in all cephalopod species (broadtail squid: 88.1%, horned octopus 94.1%, spider octopus: 97.5%). PCB isomer profiles were similar among species being hexachlorinated isomers the most abundant, followed by penta- and heptachlorobiphenyls, while tri- and tetrachlorobiphenyls made up a small percentage of the total PCB residues. Regarding coplanar congeners, non-ortho PCBs were below the detection limit in all samples and the 2,3,7,8-TCDD toxic equivalent (TEQ) concentrations were very low. The influence of biological and ecological factors (size/weight and location) on the bioaccumulation of organochlorine compounds has been discussed.  相似文献   

19.
Azmi MA  Naqvi SN  Azmi MA  Aslam M 《Chemosphere》2006,64(10):1739-1744
Persons from 14 different fruit and vegetable farm stations from Gadap (rural area), Karachi-Pakistan were examined for the presence of pesticide (cypermethrin, deltamethrin, polytrin-C, diazinon, monocrotophos, DDT and DDE) residues in their blood samples. The present study is concerned with effects of residue on the enzyme levels (GPT, GOT and ALP) as well as the health hazards of pesticide exposed persons. There is a significant increased in the enzyme levels at different stations. Exposed persons complained about liver and kidney dysfunctions and RTI. It may be concluded that exposure of multiple pesticides for prolonged period has affected the normal functioning of different organ systems and possibly produced characteristics clinical effects such as hepatitis, dyspnea and burning sensation in urine.  相似文献   

20.
Bottom-feeding fish such as flounder and killifish have been widely used in monitoring hepatic monooxygenase induction in polluted water bodies. While channel catfish are often utilized in tissue monitoring of fresh and estuarine water bodies, few data are available on their use in environmental monitoring of hepatic monooxygenase activity. In this project, the presence of CYP1A protein was verified in channel catfish through recognition by Mab 1-12-3, an antibody which recognizes the CYP1A homologue in a variety of teleost species. CYP1A protein levels and 7-ethoxyresorufin-o-deethylase (EROD) activity in laboratory control and benzo-a-pyrene (BaP)-challenged channel catfish were compared to those in feral channel catfish from Back River, an urban estuarine tributary to Chesapeake Bay. Though more variable, mean CYP1A protein levels in the field-collected fish were similar to those of the BaP-induced laboratory fish. However, EROD activity of the Back River fish was less than one half that observed in the BaP-induced laboratory fish. When normalized to CYP1A protein levels, EROD activity was slightly lower in the Back River fish than either the laboratory control or BaP-treated fish. This finding may indicate possible inhibition or inactivation of the CYP1A protein in the feral fish.  相似文献   

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