西安市2013年PM_(2.5)浓度变化分析研究

全面分析2013年西安市13个国控环境空气质量自动监测子站PM2.5监测数据。结果表明:2013年西安市环境空气中PM2.5年均值为105μg/m3,超过《环境空气质量标准》(GB 3095—2012)二级要求(35μg/m3)200.0%,污染较严重;西安市各子站PM2.5月均值总体呈两边高、中间低的"V"型趋势,全市及各子站PM2.5月均值分别为44~206、32~275μg/m3;采暖期(上半年采暖期为1—3月,下半年采暖期为11—12月)、非采暖期(4—10月)PM2.5平均值分别为156、70μg/m3;上、下半年采暖期PM2.5平均值分别为178、124μg/m3;西安市气象风力以微风为主,雨天集中在5—9月,期间PM2.5月均值小于80μg/m3。     

东莞市大气PM_(10)、PM_(2.5)、PM_1中多环芳烃/正构烷烃的污染特征和来源解析

2011年8月—2012年7月间于东莞市生活区(NC)点和工业区(ZT)点采集大气PM10/PM2.5/PM1样品,并检测分析了颗粒物上的多环芳烃(PAHs)和正构烷烃。粒径分布结果显示,PAHs和正构烷烃均主要富集在PM1上,而正构烷烃富集程度更高。PAHs环数分析结果显示,PM1中主导PAHs为6环,PM1~2.5和PM2.5~10中则为4环。利用特定比值法分析PAHs来源,结果表明,生活区NC点大气颗粒物中PAHs主要来自汽油车尾气、天然气燃烧、燃煤源和烹饪源,而工业区ZT点则主要来自柴油车尾气、燃煤和木材燃烧。通过主峰碳数、碳优势指数、植物蜡贡献率等方法分析正构烷烃来源,结果表明,化石燃料燃烧是东莞市大气颗粒物中正构烷烃的主要贡献源,其次是高等植物蜡排放,贡献率约为10.9%~28.9%。化石燃料燃烧源贡献率对PM1的贡献率明显较PM1~2.5和PM2.5~10高。     

长春大气细颗粒物中多环芳烃的季节变化及健康风险评价

为研究长春大气细颗粒物(PM_2.5)中多环芳烃(PAHs)的季节变化及健康风险评价,于2020年9月至2021年4月采集大气PM_2.5样品,测定PM_2.5中16种优先控制PAHs的浓度。结果表明,除二苯并(a, h)蒽外,其他15种PAHs均有检出,总质量浓度在0～198.00 ng/m³,平均值为67.80 ng/m³,呈冬季(平均值71.90 ng/m³)>春季(平均值70.50 ng/m³)>秋季(平均值55.20 ng/m³)的特征,PAHs的苯并(a)芘毒性当量季节变化明显,冬季(平均值4.40 ng/m³)显著高于秋季(平均值1.26 ng/m³)和春季(平均值0.38 ng/m³)。成人和儿童在冬季的平均终生致癌风险(ILCR)值分别为2.15×10^-5、2.43×10^-5,显著...     

温州城区大气PM_(2.5)中多环芳烃的污染特征与来源解析

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。     

西安大气气相中的多环芳烃

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。     

贵州贫困农村室内PM10污染水平及影响因素分析

为调查贵州贫困农村室内空气污染水平,对织金和六枝农户室内可吸入颗粒物(PM10)进行了系统采样,分析了PM10污染水平,探讨了其影响因素。结果表明:采暖期PM10的平均值为640.5μg/m3,最高质量浓度达到7 739.9μg/m3;非采暖期PM10的平均值为459.9μg/m3,最高质量浓度达到3 515.1μg/m3,与《室内空气质量标准》(GB/T 18883—2002)相比,研究区PM10的超标率为71%～92%,超标倍数最高达50.60倍。经调查可知,贵州贫困农村室内PM10污染水平与燃料类型、炉灶类型、室内通风情况等密切相关,以拌泥煤、纯煤、蜂窝煤和简易敞口灶为主,且室内通风较差。     

鞍山市城区夏季PM_(2.5)中多环芳烃组成特征及来源解析

通过采集鞍山市城市PM_(2.5)样品,使用气相色谱—质谱联用仪分析PM_(2.5)样品中的多环芳烃(PAHs)含量,并进行PAHs组成特征及来源研究。结果表明,鞍山市6个采样点13种PAHs质量浓度总和为10.54~14.26ng/m3,平均为12.08ng/m3,苯并[a]芘日均浓度均未超过《环境空气质量标准》(GB 3095—2012)日均浓度限值;低分子量PAHs比例较低,5、6环PAHs呈相对优势分布,表明交通污染源对鞍山市PM_(2.5)中的PAHs贡献较大;利用比值法和主成分分析(PCA)法对PAHs来源进行解析,两种方法均表明,PAHs污染主要来自柴油、煤炭燃烧源和焦炉源,污染类型为煤烟和交通复合型。     

南昌市夏季PM_(2.5)中多环芳烃来源解析

在南昌市设立了5个不同功能区采样点,分别为居民区、工业区、商业区、交通干线区以及郊区,于2008年夏季进行PM2.5采样,对样品进行测定和分析后,通过因子分析法判断PM2.5中多环芳烃(PAHs)的主要污染源,再利用多元线性回归法确定各主要污染源对PAHs的贡献率。结果表明,南昌市夏季PM2.5中PAHs的主要污染源为车辆排放源、高温加热源、燃煤污染源,它们对PAHs的贡献率分别为37.9%、28.2%和22.0%;要控制南昌市夏季PM2.5中的PAHs,主要是要对机动车尾气排放量进行控制,并加强机动车尾气治理工作。     

不对称街谷内PM_(2.5)浓度垂直分布特征及成因

当前细颗粒物PM2.5已成为城市环境的主要污染物,研究城市不对称街谷内PM2.5浓度的垂直分布特征,对居民日常生活与健康出行有现实意义。实验选取2013年3个不同阶段对高度在1~35 m范围的街谷进行PM2.5浓度监测,同时引用街谷内流场模型与浓度场模型,对PM2.5浓度垂直分布特征及成因进行探究。结果表明,不对称街谷受大气对流、风速、风向影响,街谷内细颗粒物存在不均匀分布特点,在较高侧随着壁面高度的增加PM2.5浓度大体呈"S"型曲线变化。同时在同一阶段监测的4天中街谷内PM2.5浓度分布特征大体一致,而阶段之间差异明显;街谷内PM2.5浓度垂直分布的最高浓度差出现在阶段1,高达75μg/m3,阶段2与阶段3浓度差相对减弱,仅在20~30μg/m3之间。通过阶段2与阶段3对比可知,北京冬季供暖燃煤对大气细颗粒物的贡献较大,导致颗粒物浓度偏高;而非采暖期气温回升,大气对流作用较强,有助于大气颗粒物扩散,因而街谷内PM2.5污染程度相对较低。     

PM_(2.5)手工标准方法与自动监测法比对分析

选取金华、衢州、温州、丽水、宁波、杭州6个城市开展PM2.5手工标准方法和自动监测法比对实验,并用相关性和相对偏差两个指标对比对结果进行分析和评价。结果表明:(1)2013年6个采样城市采集的PM2.5手工和自动监测值均具有较好的相关性(相关系数均在0.95以上),截距均在-0.010~0.010mg/m3,但斜率相差较大(衢州和丽水在0.90以上;金华、温州和杭州在0.85~0.90;宁波在0.80以下)。(2)2013年6个城市采集的PM2.5手工和自动监测值的相对偏差为-34.2%~36.5%;PM2.5手工和自动监测值相对偏差在±15%范围内的数据占总数据量的82.6%;负偏差数据占总数据量的80.0%。(3)PM2.5手工标准方法和自动监测法的比对差异与地域、季节和PM2.5浓度等条件有关。总体上,不同地区PM2.5手工与自动监测值相对偏差绝对值(︱RD︱)年平均值为衢州丽水金华宁波温州杭州;春季PM2.5手工与自动监测值︱RD︱平均值高于夏季,秋季高于冬季;各采样城市PM2.5手工和自动监测值︱RD︱平均值在高质量浓度(PM2.5手工监测值(ρ1)0.150mg/m3)下最小,中质量浓度(0.050≤ρ1≤0.150mg/m3)下最大,低质量浓度(ρ10.050mg/m3)下介于两者之间。     

Differences in Cu content in selected mushroom species growing in the same unpolluted areas in Poland

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).     

Trends in summer sulphate in Europe

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.     

Pesticides in rainfall in Europe

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.     

大气中二（口/恶）（口/英）研究进展

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.     

Residues of organochlorine pesticides in fishes in Sudan

Abstract

Cotton‐producing areas of the Centrol Sudan, bordered by the Blue and the White Nile, have been subjected to repeated applications of pesticides. This region is irrigated by a series of canals, the Gezira canals, which hold large amounts of fresh water. Lake Nubia at the Sudan‐Egypt border is another important fresh water reservoir and fisheries ground. Fish from both the Gezira and Lake Nubia showed elevated concentrations of pesticides, suggesting that continued pesticides application would endanger the equatic fauna of this region and the proposed fresh water fishery.     

Mercury in fish in Swedish lakes

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.     

Multi-Decadal Changes in Snow Characteristics in Sub-Arctic Sweden

A unique long term, 49-year record (divided into three time periods 1961–1976, 1977–1992, and 1993–2009) of snow profile stratigraphy from the Swedish sub Arctic, was analyzed with a focus on changes in snow characteristics. The data set contained grain size, snow layer hardness, grain compactness, and snow layer dryness, observed every second week during the winter season. The results showed an increase in very hard snow layers, with harder snow in early winter and more moist snow during spring. There was a striking increase in the number of observations with very hard snow at ground level over time. More than twice as many occasions with hard snow at ground level were observed between 1993 and 2009 compared to previous years, which may have a significant effect on plants and animals. The changes in snow characteristics are most likely a result of the increasing temperatures during the start and the end of the snow season.     

Pesticide distribution in an agricultural environment in Argentina

An assessment of the off-site migration of pesticides from agricultural activity into the environment in the Neuquen River Valley was performed. The aim of this study was to evaluate the distribution of pesticides in several compartments of a small agricultural sub-catchment. Soil, surface water, shallow groundwater and drift deposition were analyzed for pesticide residues. Results showed the presence of some pesticide residues in soil, surface water and shallow groundwater compartments. The highest detection frequencies in water (surface and subsurface) were found for azinphos-methyl and chlorpyrifos (>70%). In terms of concentration, the highest levels were observed in shallow groundwater for azinphos methyl (22.5 μg/L) and carbaryl (45.7 μg/L). In the soil, even before the application period had started, accumulation of residues was present. These residues increased during the period studied. Spray drift during pesticide application was found to be a significant pathway for the migration of pesticide residues in surface water, while leaching and preferential flows were the main transport routes contributing to subsurface contamination.     

Large-scale spatial variation in mercury concentrations in cattle in NW Spain

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.     

Bioaccumulation of decamethylcyclopentasiloxane in perch in Swedish lakes

Decamethylcyclopentasiloxane (D5), a high production volume chemical used in personal care products, enters the environment both via air and sewage treatment plant (STP) recipients. It has been found in fish, and there is concern that it may be a bioaccumulative substance. In this work D5 was analyzed in perch from six Swedish lakes that did not receive STP effluent, and in perch and sediment from six lakes that received STP effluent. In the lakes receiving the STP effluent, the D5 concentrations in sediment varied over three orders of magnitude and were correlated with the number of persons connected to the STP normalized to the surface area of the receiving body. In the lakes not receiving effluent, the D5 levels in perch were all below the LOQ, while D5 was above the LOQ in almost all perch from lakes that received effluent. The D5 concentrations in perch and sediment from the lakes receiving STP effluent were correlated. This shows that STP effluent is a much more important source of D5 to aquatic ecosystems than atmospheric deposition, and that the risk of adverse effects of D5 on aquatic life will be greatest in small recipients receiving large amounts of STP effluent. The bioaccumulation of D5 was compared to that of PCB 180 on the basis of multimedia bioaccumulation factors (mmBAFs), which describe the fraction of the contaminant present in the whole aquatic environment (i.e. water and surface sediment) that is transferred to the fish. In four of the six lakes the mmBAF of D5 was >0.3 of the mmBAF of PCB 180. Given that PCB 180 is a known highly bioaccumulative chemical, this indicates that the bioaccumulation of D5 in perch is considerable.