首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
The concentrations, distribution, possible sources, and potential risk of polycyclic aromatic hydrocarbons (PAHs) in surface soils were studied in Kunming, which is situated in a lake basin of the Yunnan-Guizhou plateau. 15 PAHs were analyzed in 40 surface soil samples (0–5 cm layer) collected from six types of land uses in the Kunming urban area. Meanwhile, the potential sources of PAHs in surface soils of Kunming were investigated by PAH composition ratios, isomer ratios, and principal component analysis (PCA). The total concentrations of 15 PAHs ranged from 101.64 to 6,208.25 ng/g (dry weight basis). The concentrations in different land uses increased in an order as: green space (541.43 ng/g) < education area (756.49 ng/g) < business area (810.17 ng/g) < residential area (1,034.36 ng/g) < industrial area (1,166.79 ng/g) < roadside greens (2,146.76 ng/g). The results of sources identification suggested that PAHs in surface soils of the Kunming urban area were greatly affected by combustion activities which came mainly from coal combustion and vehicular traffic. In addition, the toxic equivalency factors (TEFs) were used to estimate benzo[a]pyrene-equivalent concentration in surface soils of Kunming, and the risk level of PAHs in Kunming's urban surface soils was low as a whole.  相似文献   

2.
Hormozgan Province plays a vital role in fishery, petroleum, and industrial activities in southern Iran. However, no comprehensive studies on organic pollution have been performed. PCBs and PAHs were analyzed in surface sediments from areas receiving industrial (nine sites), river (one site), and urban (two sites) effluents. The sediment samples were collected in March and September 2010 (in dry and wet seasons) at the highest tidal time. The overall pollution level of PCBs ranged from 2.5 ± 0.8 to 462.0 ± 206.7 ng/g dry weight. CB153 congener dominated in most of the sediment samples. Congener profiles of PCBs showed close similarity with formulations of commercial products such as Aroclor 1260 and 1254 g. A wide range of 55.3 to 1231.6 ng/g dry weight was detected for ∑PAHs. Results of PCA and PCA-MLR tests confirmed both petrogenic and pyrogenic origins for PAH pollution. The higher means of ∑PAHs and ∑PCBs in industrial and urban wastewaters were found near the shore, evidencing the role of these wastewaters in the PAH and PCB contamination in Hormozgan sediment. The concentrations of PAHs and PCBs in detected hotspots exceed the U.S. NOAA sediment quality guidelines.  相似文献   

3.
Road-deposited sediment and roadside soil in the urban area of the city of Tijuana were collected and analyzed for 16 polycyclic aromatic hydrocarbons (PAHs). The ΣPAH concentration for road-deposited sediment (RDS) ranged between 460 and 2027 µg/kg with an average of 933 µg/kg. The ΣPAH concentration in roadside soil was lower than in RDS, with a range between 54 and 1863 µg/kg and a mean value of 308 µg/kg. The diagnostic ratios showed that the PAHs originated mostly from pyrogenic sources such as gasoline and diesel combustion. The results show that PAH concentration in RDS and roadside soils is low when compared with other published studies. The low PAH levels found in this study are possibly related to differences in climate, urban features, and anthropogenic activities conducted in the studied areas. The toxicity equivalent concentrations (TEQ) of PAH calculated were also low in comparison with other studies. This is probably due to the lower concentration of total PAHs and the highly toxic high-molecular-weight PAHs.  相似文献   

4.
This study was done to determine the concentration of PAHs in urban soil of Delhi (India). Surface top soil (up to 10 cm depth) samples were collected from four different sampling sites including industrial, roadside, residential, and agricultural areas of Delhi and 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs) were evaluated. Total PAH concentrations at industrial, roadside, residential, and agricultural sites were 11.46 ± 8.39, 6.96 ± 4.82, 2.12 ± 1.12, and 1.55 ± 1.07 mg/kg (dry weight), respectively, with 3–7 times greater concentrations in industrial and roadside soils than that in residential and agricultural soils. The PAH pattern was dominated by 4- and 5-ring PAHs (contributing >50% to the total PAHs) at industrial and roadside sites with greater concentration of fluoranthene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]anthracene, benzo[ghi]perylene, and pyrene, whereas, residential and agricultural sites showed a predominance of low molecular weight 2- and 3-ring PAHs (fluoranthene, acenaphthene, naphthalene, chrysene, and anthracene). Isomeric pair ratios suggested biomass combustion and fossil fuel emissions as the main sources of PAHs. The toxic equivalency factors (TEFs) showed that carcinogenic potency (benzo[a]pyrene-equivalent concentration (B[a]Peq) of PAH load in industrial and roadside soils was ~10 and ~6 times greater than the agricultural soil.  相似文献   

5.
Polycyclic aromatic hydrocarbons (PAHs) in the surface urban soils of Shenyang in Northeastern China were investigated. The total concentration of the PAHs ranged from 0.09 to 8.35 mg kg?1, with an average value of 1.51 ± 1.64 mg kg?1. 3–5-ring PAHs accounted for 90% of total PAHs. The functional areas, such as the industrial regions (4.95 mg kg?1) and main roads (1.56 mg kg?1), as well as the administrative divisions, including the districts of Shenhe (1.49 mg kg?1), Heping (2.08 mg kg?1), and Tiexi (2.14 mg kg?1), were heavily polluted by PAHs. The diagnostic ratios and principal component analysis (PCA) for PAHs indicate that the pollutants probably originated primarily from coal combustion and petroleum sources. The Nemerow composite index, used to assess environmental quality, shows that the soil samples were heavily polluted with PAHs, and although 52.8% of the soil sampling sites were safe, 47.2% of the soil sampling sites registered different grades of PAH pollution. The PAH contamination in Shenyang emphasizes the need for controlling fossil fuel combustion and traffic exhaust.  相似文献   

6.
Abstract

This study was conducted to examine the impact of vehicular traffic on the contamination status of urban traffic sites in Beijing with respect to polycyclic aromatic hydrocarbons (PAHs). The soil and Pinus pinea needle samples were collected at 12 sites on Three Ring Road in Beijing, China, from July 2009 to March 2010. Total PAH concentrations at traffic sites ranged from 113.86 to 2226.24 ng g?1 with an average value of 658.71 ± 742.41 ng g?1 in soil samples and 112.03 to 2016.80ng g?1 with an average value of 680.29 ± 485.61 ng g?1 in needle samples. The PAH pattern was dominated by two- and three-ring PAHs (contributing >80% to the total PAHs) at all the 12 traffic sites. Seasonal variations of PAHs compounds indicated the PAHs concentrations in autumn and winter were higher than those in spring and summer due to temperature effects. This work indicates that the low ring PAHs were the major profile at the roadside of a busy street with heavy traffic in Beijing.  相似文献   

7.
Concentrations and profiles of polycyclic aromatic hydrocarbons (PAHs) were determined in selected popular brands of canned fish (mackerel, sardine, and tuna) consumed in Nigeria with a view to providing information on the health risk associated with consumption of these products. The concentrations of PAHs were measured by gas chromatography equipped with flame ionization detection (GC-FID) after dichloromethane/hexane extraction and clean-up. The concentrations of Σ16 PAHs in these brands of canned fish varied from 174.6 to 350.8 μg/kg, 187.4 to 592.5 μg/kg, and 204 to 264.6 μg/kg for mackerel, sardine, and tuna, respectively. Benzo(a)pyrene was detected in 48% of the investigated brands at concentrations higher than the maximum tolerable limit of 5 μg/kg. The daily intake of PAHs from the consumption of any brand of these canned fish ranged from not detected (nd) to 54.3 ng BaP/kg bw/day, nd to 56.4 ng PAH2/kg bw/day, nd to 86.4 ng PAH4/kg bw/day, and nd to 153.7 ng PAH8/kg bw/day. The estimated margin of exposure (MOE) values (BaP-MOE, PAH2-MOE, PAH4-MOE, and PAH8-MOE) in a significant proportion of the brands was less than 10,000, which indicates a potential health risk for the consumers of these brands of canned fish.  相似文献   

8.
Polycyclic aromatic hydrocarbons (PAHs) are of global concern due to their ubiquitous presence, toxicity, and carcinogenicity. No data on PAHs in soils from South Africa have been published, even though it has the largest economy and industrial base in Africa. During this initial assessment, the levels of PAHs were determined in soils and sediments collected from central South Africa, specifically targeting industrial, residential, and agricultural areas. Analysis was performed by gas chromatography/mass spectrometry (GC/MS). The total concentration of PAHs (Σt-PAH) ranged between 44 and 39,000 ng/g, dw and the concentration of carcinogenic PAHs (Σc-PAH) ranged between 19 and 19,000 ng/g, dw. Pyrogenic processes were the most likely sources, with minimal petrogenic contributions. PAH levels were in the same range as levels reported from other countries, and the majority of the sites did not exceed Canadian environmental quality guidelines. Based on assumptions for dermal contact and ingestion of PAH-contaminated soil, we provisionally calculated only a small increase in cancer risk, but additional PAH inhalation could add considerably to this risk. Our data indicates a need for more analysis in industrial and residential areas, and should include air.  相似文献   

9.
Coking is one of the most important emission sources of polycyclic aromatic hydrocarbons (PAHs) in China. Investigation of the contamination, distribution, and sources of PAHs in agricultural soils around Rong Xin coking plant, China, was conducted, and the potential human health risks were addressed. The total concentration of the 16 PAHs (∑16PAHs) on the United States Environmental Protection Agency priority list had a range from 1774 to 4621 µg/kg (mean 3016 µg/kg). Meanwhile, seven carcinogenic PAHs (∑PAH7c) owned the total concentrations of 684–2105 µg/kg, and they had the benzo[a]pyrene equivalent (BaPeq) concentrations at 139.616–1672.850 µg/kg. All soil samples were dominated by PAHs with two to four rings. Data analyses for the potential sources of PAHs showed that the PAHs in soils were principally from pyrogenic sources. Ecological risk assessment of soil PAHs showed that the BaPeq concentrations of ∑PAH7c accounted for 99% of the total ∑16PAHs, being a major carcinogenic contributors of ∑16PAHs. Higher levels of PAHs and higher total BaPeq concentrations in this study indicate a potential carcinogenic risk for humans. Therefore, long-term exposure to coking plants may increase the PAH concentrations in the environment and further raise a potential risk to human health.  相似文献   

10.
Polycyclic aromatic hydrocarbons (PAHs) have become a major type of persistent organic pollutant (POPs) in the world. To well understand the occurrence, spatial distribution and source apportionment of 16 PAHs in different media in Beijing, a comprehensive study was conducted based on 337 obtained and subsequently selected samples in four specific media, including soil, road dust, surface water and atmosphere covering sampling time spanning from 2005 to 2014. Mean concentrations of Σ16 PAHs in soils (878.5 μg/kg) decreased from inner city to exterior areas with different land uses decreased in the order of industrial estate (2510 μg/kg)>educational area (1331 μg/kg)>Park (783 μg/kg)>cultivated (650 μg/kg)>roadside (583 μg/kg)>residential (568 μg/kg)>green area (478 μg/kg)>forest area (125 μg/kg). Meanwhile, PAHs concentrations in branch roads were slightly higher than trunk roads and mainly concentrated in urban areas (1136 μg/kg). Affected by industrial and residential areas, PAHs concentrations in downstream surface rivers were much higher than upstream surface rivers (475 ng/L). Due to strong mobility, PAHs concentrations in atmosphere were not equally distributed around the study area (157.59 ng/m3). The result of source apportionment determined by diagnostic ratios method indicated PAHs in multiple media in Beijing are mainly from coal and biomass combustion.  相似文献   

11.
This study was conducted to investigate the occurrence, distribution, and source of 16 polycyclic aromatic hydrocarbons (PAHs) in the Hanjiang River Basin and the Danjiangkou (DJK) Reservoir. The concentrations of total PAHs in surface water, sediments, and bank soils ranged from 9.42 to 137.94 ng/l, 86.23 to 2514.93 ng/g, and 133.17 to 671.93 ng/g dry weight, respectively. The composition pattern of PAHs showed that 3-ring PAHs were dominated in all of the samples, while the proportion of high molecular weight PAHs (5- to 6-ring PAHs) in sediments and bank soil samples was almost three times higher than water. The source apportionment analysis showed that most of the PAHs in water were derived from sources of petroleum and combustion, while combustion was the predominant source of PAHs in sediments and bank soils. The methods based on toxic equivalency factors, risk quotient, and incremental lifetime cancer risk were used to assess the ecosystem risk and potential health risk of PAHs. The risk assessments showed that PAHs in the DJK Reservoir were out of potential health risk, but the ecological risk for majority of 16 PAHs was in the moderate level.  相似文献   

12.
Sixteen USEPA priority polycyclic aromatic hydrocarbons (PAHs) were analyzed by gas chromatography–mass spectrometry. Twenty samples were collected from the surface sediments of Haizhou Bay in this survey. This research aimed to identify the PAHs' contamination level, composition pattern, pollution sources, and assess the ecological risk of PAHs. The results showed that the sum of PAH concentrations ranged from 116.6 ng g?1 to 2414.9 ng g?1 (mean: 662.42 ng g?1), which is higher than the reported values for different wetlands worldwide. Three- and four-ring PAHs (accounts for more than 70% of the total PAH content) were predominant in the wetland sediment. The PAHs source distribution in the surface sediments were determined using diagnostic ratio and PCA/MLR. Consequently, multiple PAHs sources were found. Of the total PAH, 79.25% was derived from vehicular emission, 20.75% from coal combustion. The effect range low/effect range median (ERL/ERM) values indicated a low toxicity risk level. However, the fluoranthene concentrations exceeded the ERL level, and even the ERM level, in some stations. The mean effects range–median quotient (M-ERM-Q) suggests a low ecological risk for the PAHs in the sediments.  相似文献   

13.
Polycyclic aromatic hydrocarbons (PAHs) are typically persistent organic pollutants with hypertoxicity and widespreading, attracting increasing attention in recent years. Six paddy land sites soils irrigated from different rivers in the Nansi Lake area of Shandong Province, China, were studied to analyze and assess the source and risk of PAHs.Analysis revealed total PAHs (TPAHs) concentrations in topsoil ranging from 57.49 to 2046.47 μg kg?1, meanwhile, Weishan County (WS) was highly contaminated primarily from coal combustion based on the Nemerow composite index and geochemical indices.Canonical correspondence analysis (CCA) suggested that bacterial species were affected by pH, TPAHs, and soil organic matter (SOM), while covariables analysis confirmed that most effects of PAHs on bacterial diversity were attributed to the PAHs effect alone rather than the combined effects of PAHs and soil properties. The average daily human exposure (ADE) in children was approximately 2 times higher than that in adults, and the exposure paths values followed a decreasing order, oral intake > skin contact > inhalation. Furthermore, the WS site and another rice test field (TF) presented potential cancer risks and required further investigation. Therefore, the study has important theoretical significance for the control of PAHs pollution in this field, providing a scientific basis for health assessment.  相似文献   

14.
南亚热带典型地区农业土壤中多环芳烃和有机氯农药研究   总被引:3,自引:0,他引:3  
郝蓉  宋艳暾  万洪富  彭少麟 《生态学报》2007,27(5):2021-2029
参考美国EPA标准方法对南亚热带潮汕地区农业土壤中持久性有机污染物多环芳烃(PAHs)和有机氯农药(OCPs)进行分析,并对其分布和来源进行研究,最后探讨了不同种植方式下污染物的污染特征。结果表明:该区农业土壤中PAHs含量范围从22.1ng/g到1256.9ng/g,与其它地区的污染程度和一些土壤环境质量标准相比,该区处于中等污染水平。高温裂解是土壤PAHs的主要来源。OCPs在被禁止20a后在土壤中仍有残留,残留水平从4.6ng/g到1021.5ng/g,其中HCHs和DDTs的残留未超过国家土壤环境质量标准。早期使用残留是其主要污染源,但新近仍有DDT和硫丹的输入。PAHs和OCPs的污染主要集中在土壤表层和亚表层,且随着深度的加深,污染逐渐减少,但40cm以下,污染变化很小。菜地土壤PAHs污染水平低于稻田土壤,而OCPs污染水平高于稻田土壤。  相似文献   

15.
To investigate the occurrences of polychlorinated biphenyls (PCBs) in suburban vegetable soils of Changchun area, Northeast China, 106 urban vegetable soil samples were collected from Changchun City, Nongan County, Dehui City, Yushu City, Jiutai City, Shuangyang District. We analyzed the concentrations, compositions and sources of 7 PCBs in top soils of Changchun area, and evaluated the non-carcinogenic and carcinogenic risk of PCBs pollution to exposed population. The total concentrations of 7 PCBs ranged from 1.31 to 148 ng/g dry weight (dw) with a mean value of 42.0 ng/g and dominated by Hepta-CBs and Penta-CBs. Principal component analysis (PCA) revealed that PCB pollution in soils of Changchun area mainly related to transportation, vehicle emissions, paints and other industries. Human health risk assessment showed that the cumulative non-carcinogenic and the cumulative carcinogenic risk in children and adults in the industrial land and residential land were acceptable, considering only 7 PCBs homologues were analyzed in this study, the actual risk could be higher.  相似文献   

16.
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants of the environment. But is their microbial degradation equally wide in distribution? We estimated the PAH degradation capacity of 13 soils ranging from pristine locations (total PAHs ≈ 0.1 mg kg?1) to heavily polluted industrial sites (total PAHs ≈ 400 mg kg?1). The size of the pyrene- and phenanthrene-degrading bacterial populations was determined by most probable number (MPN) enumeration. Densities of phenanthrene degraders reflected previous PAH exposure, whereas pyrene degraders were detected only in the most polluted soils. The potentials for phenanthrene and pyrene degradation were measured as the mineralization of 14C-labeled spikes. The time to 10% mineralization of added 14C phenanthrene and 14C pyrene was inversely correlated with the PAH content of the soils. Substantial 14C phenanthrene mineralization in all soils tested, including seven unpolluted soils, demonstrated that phenanthrene is not a suitable model compound for predicting PAH degradation in soils. 14C pyrene was mineralized by all Danish soil samples tested, regardless of whether they were from contaminated sites or not, suggesting that in industrialized areas the background level of pyrene is sufficient to maintain pyrene degradation traits in the gene pool of soil microorganisms. In contrast, two pristine forest soils from northern Norway and Ghana mineralized little 14C pyrene within the 140-day test period. Mineralization of phenanthrene and pyrene by all Danish soils suggests that soil microbial communities of inhabited areas possess a sufficiently high PAH degradation capacity to question the value of bioaugmentation with specific PAH degraders for bioremediation.  相似文献   

17.
The characterizations of residue levels and sources of organochlorine pesticides (OCPs) in soils are necessary to evaluate the potential pollution and risks of OCPs to the ecosystems and human health. A total of 51 surface soil samples were collected from peri-urban vegetable fields of Changchun and 13 OCPs were analyzed to learn the composition, spatial distribution and sources. The concentrations were in the ranges of 0.94–107.8 ng g?1 for DDTs, 0.89–98.3 ng g?1 for HCHs, 0.22–18.20 ng g?1 for Chlordanes, nd–4.49 ng g?1 for aldrin and nd–9.66 ng g?1 for dieldrin, respectively. The total OCPs concentrations ranged from 2.44 to 177.1 ng g?1 and the higher residues were mainly distributed in northeast and southwest sites, as well as sites along the Yitong River. According to the concentrations and detection frequencies, DDTs and HCHs were the most dominant compounds. Compositional analysis and principal component analysis suggested that DDT, HCH and chlordane in most soil samples derived from historical application except the slight fresh introduction at some locations. There exist a variety of OCPs residues in peri-urban vegetable soils of Changchun, but it is still safe and suitable for agricultural production for the most part, and some specific locations with high OCPs residues ought to be a cause for concern.  相似文献   

18.
Although reservoirs in China are of great significance, very few studies on risk assessment have been reported for reservoirs. This study investigated distribution characteristics, cancer and ecological risks, and source diagnosis of 16 priority polycyclic aromatic hydrocarbons (PAHs) in sediments from Shitou Koumen Reservoir in Jilin Province, China. A total of 12 sediment samples were collected from the reservoir in August (wet season) 2014. Total PAH concentrations in sediment samples ranged from 1294.51 ng/g to 2755.35 ng/g with a mean concentration of 1757.54 ng/g. For individual PAHs, average concentration of Nap was the highest, 800.56 ng/g, while Acy, Fla, BkF, and DahA were undetected in sediment samples. Light PAHs (2–3 rings) accounting for 74.21% was a dominant PAH compositional pattern. Pearson correlation analysis was carried out; results showed that total PAHs was strongly correlated with the highly enriched sedimentary PAHs, and pH was a major factor in controlling PAH distribution. Lifetime cancer risk was employed to assess cancer risk; results indicated that the fish-culturing area was exposed to cancer risk. The molecular diagnostic ratios of isomeric PAHs were applied to identify possible PAH sources; primary PAH sources were identified as oil-related activities, burning agricultural wastes, vehicular emissions, and industrial discharges.  相似文献   

19.
To investigate the contamination level, distribution, possible source, and human exposure risk of polycyclic aromatic hydrocarbons (PAHs) in the urban traffic environment, 15 PAHs were measured in 34 road dust samples (particle size < 25 μm) collected from three grades of roads and park paths in Xinxiang, China. ΣPAHs concentrations ranged from 311 to 21200 ng g?1, with a mean of 5890 ng g?1 and decreased in the following order: main roads (7650 ng g?1) > collector streets (7410 ng g?1) > bypasses (2970 ng g?1) > park paths (1570 ng g?1), indicating that significant positive correlation existed between PAH contamination and traffic density. PAHs in all samples were dominantly composed of 4-ring PAHs, accounting for 44.8% of the total. Pyrene, fluoranthene, and chrysene were the predominant individual components and accounted for 14.7% (1.2–19.2%), 12.9% (3.3–20.3%), and 11.0% (2.5–18.6%) of ΣPAHs, respectively. The specific isomer ratios indicated that traffic emission was the dominant source of PAHs in road dust. The incremental lifetime cancer risk values showed that cancer risk from exposure to road dust–borne PAHs was acceptable for local residents in Xinxiang.  相似文献   

20.
Soil and sediment samples from New Orleans have been collected and analyzed for contamination by 16 polycyclic aromatic hydrocarbons (PAHs) and 8 trace metals. Total PAH contents were found to vary from 40 μ g/kg to 40,000 μ g/kg, and concentrations of total metals varied in the range of 80 mg/kg and 7600 mg/kg. Source analysis of PAHs using diagnostic concentration ratios such as phenanthrene/anthracene and fluoranthene/ pyrene indicated that PAHs found at elevated concentrations in New Orleans soils and sediments were of pyrolytic origins. Spearman rank bivariate correlation analysis revealed significant correlations between soil PAHs and metals (r = 0.80, p < 0.0001) and between sediment PAHs and metals (r = 0.62, p < 0.05), suggesting common pollution sources for the two groups of environmental pollutants. Strong correlations were also found between Pb and Zn in soils (r = 0.93, p < 0.0001) as well as in sediments (r = 0.65, p < 0.05).  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号