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1.
使用中流量采样器采集温州城区2015年4个季节的大气PM_(2.5)样品,利用气相色谱(GC)—质谱(MS)联用仪对PM_(2.5)样品中16种优先控制的多环芳烃(PAHs)进行分析,研究PM_(2.5)中PAHs的污染特征及其可能来源。结果显示,PM_(2.5)中总PAHs质量浓度为5.12~81.59ng/m~3,且表现为冬季秋季春季夏季,季节性变化特征明显。比值法和主成分分析显示,温州城区大气PM_(2.5)中PAHs的主要污染源是燃煤、机动车尾气以及生物质燃烧。总PAHs日均毒性当量浓度为0.44~11.28ng TEFs/m~3,平均值为3.44ng TEFs/m~3。成人和儿童的终生超额致癌风险(ILCR)年均值分别为7.11×10~(-7)、4.98×10~(-7),表明温州城区PM_(2.5)中PAHs对人体健康影响水平较低,在可接受范围内。  相似文献   

2.
在乌鲁木齐市南、北设置2个采样点,从2011年3-12月采集可吸入颗粒物(PM2.5、PM2.5-10)样品,分析了美国环境保护署优控的13种多环芳烃(PAHs)的浓度,采用比值法、主成分分析法和多元线性回归法对乌鲁木齐市大气PM2.5、PM2.5-10中PAHs的来源进行了分析。结果表明,科学院站PM2.5中13种PAHs的总质量浓度平均值为247.2ng/m3,变动范围为1.14~2 113.33ng/m3;新大站PAHs的总质量浓度平均值为240.84ng/m3,变动范围为4.96~1 359.41ng/m3。而科学院站PM2.5-10中13种PAHs的总质量浓度平均值为57.78ng/m3,变动范围为1.18~519.87ng/m3;新大站的总质量浓度平均值为49.18ng/m3,变动范围为1.38~412.52ng/m3。比值法分析结果表明,所采集样品的2/3来自煤和生物质的燃烧排放;主成分分析法和多元线性回归分析法结果表明,采暖期汽油和煤源对PM2.5中总PAHs的贡献率为46%,而非采暖期混合源的贡献率高达85%。采暖期汽油和柴油源对PM2.5-10中总PAHs的贡献率为66%,而非采暖期混合源的贡献率为78%。  相似文献   

3.
利用PUF被动采样器于2008年8月—2009年7月采集了西安大气样品,研究了大气气相中多环芳烃(PAHs)的含量和季节分布特征。结果表明,西安大气气相中16种美国EPA优控的PAHs(Σ16PAHs)质量浓度为10.9-489.6 ng/m3(平均为143.4 ng/m3),四季具有明显的季节差异,依次为夏季(62.5 ng/m3)〈春季(80.1 ng/m3)〈秋季(175.8 ng/m3)〈冬季(255.2 ng/m3)。气相中PAHs主要以3-4环为主,占总量的86.5%-94.1%。利用主成分分析法判断四季气相中PAHs的污染来源类型,主要为燃煤和机动车尾气及生物质燃烧的复合源。  相似文献   

4.
2012年3-8月对北京西三环地区大气颗粒物进行分级采样,利用气相色谱(GC)/质谱(MS)联用仪对颗粒物中多环芳烃(PAHs)含量进行测定.结果表明,检出的16种PAHs总质量浓度(∑16PAHs)平均为46.73ng/m3;苯并[a]蒽(BaA)等6种单体浓度与∑16PAHs呈良好线性关系;PAHs粒径分布特征表明,其更易富集在细颗粒物上;不同环数PAHs分布特征为:3环>4环>5环>6环>2环,随着颗粒粒径减小,高环数PAHs含量增加.温度、湿度和紫外线(UV)指数与∑16PAHs呈负相关.通过特征化合物比值分析法对PAHs进行源解析发现,采样期间PAHs主要来源为燃烧源,交通源影响微弱.  相似文献   

5.
在武汉市工业区和交通区展开了PM_(2.5)样品采集,研究了PM_(2.5)中二元羧酸的化学组成、污染水平及来源。二元羧酸在工业区为103.1~2 219.2ng/m~3,年平均值为958.4ng/m~3;在交通区为66.9~2 176.8ng/m~3,年平均值为749.7ng/m~3。丙二酸/丁二酸(C_3/C_4,质量比,下同)表明,武汉市二元羧酸主要来自机动车尾气排放;己二酸/壬二酸(C_6/C_9)表明,二元羧酸的人为源贡献大于自然源。正定矩阵因子分解(PMF)模型解析结果显示,工业区中二次源占13.7%,建筑扬尘占23.1%,机动车尾气排放占37.0%,生物质燃烧占26.2%;交通区中二次源占8.9%,建筑扬尘占24.9%,机动车尾气排放占51.8%,生物质燃烧占14.4%。潜在源区贡献因子(PSCF)分析得出,武汉市夏季二元羧酸主要受到南部季风的影响,冬季主要受到西部冷空气的影响。  相似文献   

6.
采用稀释通道采样系统对北京市部分污染源排放的PM_(2.5)进行了采集,用气相色谱-质谱-质谱法分析了PM_(2.5)中24种多环芳烃(PAHs)的浓度,获得典型排放源PM_(2.5)中PAHs成分谱。结果表明,不同种类污染源排放的PAHs的组分浓度差异比较大,形成的百分浓度轮廓图有各自的特征。生物质燃烧和化石燃烧排放的PM_(2.5)中PAHs含量高于其他污染源;燃煤电厂和供暖/工业锅炉排放的PM_(2.5)中低环数的PAHs比例较高,而生物质燃烧和餐饮源则是高环数的污染物比例较高。燃烧温度高,燃烧较充分,采用布袋除尘方式的污染源排放的PAHs含量要低于其他污染源。  相似文献   

7.
在广西省河池市的金城江、南丹、大厂和车河4个采样点采集了环境空气PM_(10)样品,分析了25种金属元素,重点解析了19种重金属的污染特征,并运用主成分分析对其来源进行了讨论。结果表明:(1)河池市4个采样点的环境空气PM_(10)24h平均质量浓度均未超过《环境空气质量标准》(GB 3095—2012)一级标准(50μg/m~3);(2)19种重金属总质量浓度平均值为1 378.7~2 796.8ng/m~3,占PM_(10)的质量分数为3.73%~7.35%;(3)Zn、Pb、Fe 3种重金属在4个采样点的浓度均值均较高,是河池市环境空气PM_(10)中的主要重金属,占重金属总质量的74%~89%;(4)河池市环境空气PM_(10)中重金属主要有地壳源、铅锌冶炼源和其他工业源3个来源。  相似文献   

8.
为研究西南岩溶地区城市近郊型地下河沉积物中多环芳烃(PAHs)的污染特征及来源,选择南宁市清水泉地下河进行分析,沿地下河流动方向共采集8个表层沉积物样品,并检测16种PAHs的含量。结果表明,地下河表层沉积物中总PAHs为257.7~609.5ng/g(基于表层沉积物干质量计算),整体浓度处于中等污染水平;从PAHs组成来看,16种PAHs均被检出,且含量表现为4环PAHs5~6环PAHs2~3环PAHs;空间分布规律呈下游中游上游的趋势,且2~3环PAHs占比先增大后降低,而4~6环PAHs占比变化则相反;不同区域的PAHs来源各不相同,上游地区PAHs为燃烧来源,中游地区PAHs为石油来源,下游地区为混合来源,燃烧来源、石油来源与混合来源对PAHs的贡献率分别为28.4%、16.5%和55.1%。  相似文献   

9.
基于2014—2016年广州PM_(2.5)浓度逐时观测数据,研究了广州PM_(2.5)污染变化特征及其与气象因子的关系,确定了影响广州大气能见度的PM_(2.5)浓度阈值。结果表明:(1)2014—2016年广州PM_(2.5)质量浓度平均为32.7μg/m3,广州1月PM_(2.5)污染最重,轻度、中度、重度污染频率合计达20.16%;(2)PM_(2.5)浓度与风速、降水、气温、能见度呈负相关,与相对湿度、气压呈正相关;(3)广州地区在南风的条件下PM_(2.5)浓度最低,风速小于2m/s的偏北风下易出现污染;(4)PM_(2.5)浓度与相对湿度共同影响广州能见度的变化,随着相对湿度的增加,PM_(2.5)浓度的敏感阈值不断减小,通常当PM_(2.5)高于37.3μg/m3时,控制PM_(2.5)对改善城市能见度成效相对缓慢,而当PM_(2.5)浓度低于此阈值时,降低PM_(2.5)将显著提高大气能见度。  相似文献   

10.
为探讨石家庄秋季PM_(2.5)中低分子量有机酸组成特征与来源,于2017年9—10月对石家庄PM_(2.5)进行采样并测定了3种低分子量有机酸(甲酸、乙酸、草酸)浓度,还测定了水溶性无机离子(Cl~-、NO_3~-、SO_4~(2-)、K~+、Na~+、Ca~(2+)、Mg~(2+)、NH_4~+)辅助讨论有机酸来源。结果发现,石家庄秋季PM_(2.5)中草酸浓度高于甲酸和乙酸,而甲酸和乙酸浓度接近,甲酸、乙酸和草酸的质量浓度分别为20~240、50~280、60~1 130ng/m~3。石家庄秋季PM_(2.5)中低分子量有机酸受自然源和人为源的混合影响,以人为源占主导,其中甲酸和乙酸的同源性较高。甲酸的可能来源为工业燃煤、交通汽车尾气排放、生物质燃烧、土壤和扬尘。乙酸的可能来源为工业燃煤、交通汽车尾气排放、生物质燃烧、生活污水、土壤和扬尘。草酸的可能来源为交通汽车尾气排放、大气氧化反应、生物质燃烧、土壤和扬尘、生活污水。  相似文献   

11.
Pesticides in rainfall in Europe   总被引:1,自引:0,他引:1  
Papers and published reports investigating the presence of pesticides in rainfall in Europe were reviewed. Approximately half of the compounds that were analysed for were detected. For those detected, most concentrations were below about 100 ng/l, but larger concentrations, up to a few thousand nanograms per litre, were detected occasionally at most monitoring sites. The most frequently detected compounds were lindane (gamma-HCH) and its isomer (alpha-HCH), which were detected on 90-100% of sampling occasions at most of the sites where they were monitored. For compounds developed more recently, detection was usually limited to the spraying season. A classification of pesticides according to their deposition pattern is proposed.  相似文献   

12.
The aim of the study was to estimate copper (Cu) accumulation efficiency in whole-fruiting bodies of 18 edible and non-edible wild growing mushrooms collected from 27 places in the Wielkopolska Voivodeship. Mushrooms were collected each time from the same places to estimate the diversity in Cu accumulation between tested mushroom species within 3 consecutive years of study (2011–2013). The study results revealed various accumulation of Cu in the whole-tested mushroom fruiting bodies. The highest mean accumulation of Cu was observed in Macrolepiota procera (119.4 ± 20.0 mg kg?1 dm), while the lowest was in Suillus luteus and Russula fellea fruiting bodies (16.1 ± 3.0 and 18.8 ± 4.6 mg kg?1 dm, respectively). Significant differences in Cu accumulation between mushroom species collected in 2011 and in the two following years (2012 and 2013) were observed. The results indicated that sporadic consumption of these mushrooms was not related to excessive intake of Cu for the human body (no toxic influence on health).  相似文献   

13.
Mercury (Hg) is a highly toxic environmental contaminant and man-made emissions account for between a quarter and a third of total atmospheric levels. Point discharges, particularly coal-burning power stations, are major sources of atmospheric Hg and can result in marked spatial variation in mercury deposition and subsequent uptake by biota. The aims of this study were to quantify the extent to which major point and diffuse sources of atmospheric Hg emissions affected accumulation of Hg by biota throughout Galicia and Asturias, two of the major regions in northwest Spain. We did this by relating renal Hg concentrations in locally reared cattle (n=284) to the proximity of animals to point and diffuse sources of Hg emissions. Mercury residues in calf kidneys ranged between non-detected and 89.4 g/kg wet weight. Point discharges from coal-fired power plants in Galicia had the most dominant impact on Hg accumulation by calves in Galicia, affecting animals throughout the region and explaining some two-thirds of the variation in renal residues between animals located directly downwind from the plants. The effects of more diffuse emission sources on Hg accumulation in calves were not distinguishable in Galicia but were detected in cattle from neighbouring Asturias. The impact of both point and diffuse sources in elevating environmental levels of bioavailable Hg and subsequent accumulation by cattle extended to approximately 140-200 km downwind from source.  相似文献   

14.
Mercury in fish in Swedish lakes   总被引:5,自引:0,他引:5  
The aim of this work has been to try to obtain a picture of the past, present and future mercury situation in fish in Swedish lakes, to make an estimate of the number of lakes threatened by 'blacklisting', and to see if the data can be used to reveal anything about the impact of liming on the Hg content in pike. The register contains a broad set of data from 1456 lakes. The main results are as follows. Trend analyses indicate that the Hg content in 1-kg pike seems to increase with time. This is interesting since there has been a significant decrease in mercury emissions from Swedish industries during the last two decades. High Hg contents in 1-kg pike appear in a very characteristic pattern, linked to specific sources of Hg emission. The data indicate that old Swedish 'sins' are still causing a lot of problems. The factors governing the leakage of Hg from soils to water ought to be a very important topic for further studies. The Hg content in pike shows the highest correlation with the following parameters: Hg in surficial sediments, pH, distance from point source and water hardness, lake water alkalinity and conductivity, water retention time, size of drainage area and lake surface. A formula which provides the best possible degree of explanation (r2 = 0.78) has been derived. At present there are about 250 lakes 'blacklisted' in Sweden due to high Hg content in fish. Our data show that there are at least 9400 lakes that ought to be 'blacklisted' today. A successful liming operation will alter the chemical conditions in lakes and also decrease the Hg content in fish.  相似文献   

15.
A trend analysis of the sulphate concentration in Europe in the summer half-year was performed. Data from various measuring networks were analysed, but only stations with quality assured sampling methods and a record of more than 10 years were included in the study. 1978 served as the reference year for the trend, because in that year most stations started operation. The relatively dense network in Belgium provided the most valuable data, as evidenced by the fact that two sites at a distance of only 10 km apart correlated better than 95% over a month. The two sites also show a correlation of better than 90% over a season with two other stations at distances of 45 and 95 km. The relative decrease in summer-sulphate at the four stations in Belgium, as analysed by linear regression, was 3.3% per year which corresponds to an absolute decrease of 0.42 μgm−3 per year. In the Netherlands the average yearly decrease in summer-sulphate at two stations was 3.5% (−0.34 μgm−3). In other countries stations were further apart or only a single site wits in use, which limits the representativeness of the data. In northwestern Germany, a region with several monitoring stations, a yearly averaged decrease of 3.0% occurred. The lower absolute decrease (0.25 μgm−3) per year compared to that in the two neighbouring countries reflects the lower summer-time sulphate concentrations. In the remainder of Germany the average decrease was 1.6%. In South-Scandinavia the yearly relative decrease at two sites was 2.6% (0.13 μgm−3 absolute). There was no significant trend in the U.K. Al the Polish station the levels increased, it decreased at the Hungarian and Austrian station and remained constant at the Czechoslovakian site. Reasons for omission of the data from France from the trend analysis are discussed.  相似文献   

16.
We investigated the occurrence, source and exposure time of lead poisoning in whooper swans (Cygnus cygnus cygnus) and Bewick's swans (Cygnus columbianus bewickii) in Japan during the winters of 1984-1987. Concentrations of lead in various tissues and physiological evidence of lead shot in some birds indicated that lead shotgun pellets were the source of lead, and exposure occurred after the birds arrived in Japan. Mortality probably occurred within 30 days after exposure to, and retention of, lead shot in the gizzard.  相似文献   

17.
Residues of five pesticides in surface water were surveyed during 2001 and 2003 in the Traiguen river basin in Southern Chile. Simazine, hexazinone, 2,4-D, picloram herbicides and carbendazim fungicide were selected through a pesticide risk classification index. Six sampling stations along the river were set up based on agricultural and forestry land use. The water sampling was carried out before and after the pesticide application periods and in correspondence to some rain events. Pesticides were analyzed by HPLC with DAD detection in a multiresidue analysis. During 2001, in the first sampling campaign (March), the highest concentrations of pesticides were 3.0 microg l(-1) for simazine and hexazinone and 1.8 microg l(-1) for carbendazim. In the second sampling (September), the highest concentration were 9.7 microg l(-1) for 2,4-D, 0.3 microg l(-1) for picloram and 0.4 microg l(-1) for carbendazim. In the last sampling period (December), samples indicated contamination with carbendazim fungicide at levels of up to 1.2 microg l(-1). In sampling carried out on May 2003, no pesticides were detected. In October 2003, the highest concentrations of pesticides were 4.5 microg l(-1) for carbendazim and 2.9 microg l(-1) for 2,4-D. Data are discussed in function of land use and application periods of the products, showing a clear seasonal pattern pollution in the Traiguen river. Risk assessment for these pesticides was calculated by using a risk quotient (RQ = PNEC/PEC). For picloram the calculated RQ < was 0, which indicates that no adverse effects may occur due to the exposure to this herbicide in the Traiguen river basin. For 2,4-D, simazine, hexazinone, carbendazim RQ > 1, meaning that adverse effects could occur and it is necessary to reduce pesticide exposure in surface waters. It is recommended to continue with a pesticide monitoring program and the implementation of ecotoxicological testing with local and standardized species in order to consider the probability of effects occurrence, with less uncertainty. Thus, it will be more feasible to make some recommendations to regulatory agencies regarding the pesticide use.  相似文献   

18.
二(口/恶)(口/英)是世界公认的强致癌物质,对人体健康危害极大.近年来,大气中二(口/恶)(口/英)的研究已成为各国环境化学家研究的热点.本文总结了近年来国际上有关大气中二(口/恶)(口/英)研究的进展情况,以及所取得的主要研究成果,并在此基础上指出了我国目前研究中存在的问题及以后所应开展的工作.  相似文献   

19.
20.
Toxic metals are bioaccumulated by insectivorous mammals but few studies (none from Britain) have quantified residues in bats. We measured renal mercury (Hg), lead (Pb) and cadmium (Cd) concentrations in bats from south-west England to determine how they varied with species, sex, age, and over time, and if they were likely to cause adverse effects. Residues were generally highest in whiskered bats (Myotis mystacinus). Compared with other species, pipistrelle (Pipistrellus spp) and Natterer's bats (Myotis nattereri) had significantly lower kidney Hg and Pb concentrations, respectively. Renal Hg increased over time in pipistrelles but the contributory sources are unknown. Kidney Pb did not decrease over time despite concurrent declines in atmospheric Pb. Overall, median renal metal concentrations were similar to those in bats from mainland Europe and 6- to 10-fold below those associated with clinical effect, although 5% of pipistrelles had kidney Pb residues diagnostic of acute lead poisoning.  相似文献   

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