空气中多环芳烃的研究进展

介绍了国内对大气中气态,颗粒态ＰＡＨｓ的研究概况,室内外空气中ＰＡＨｓ污染与城市交通间的相关性,ＰＡＨｓ总量代表物,硝基ＰＡＨｓ及人体接触ＰＡＨｓ的生物指标。     

多环芳烃的光致毒效应

多环芳烃（ＰＡＨｓ）是一类常见的污染物,过去对其毒性的研究主要集中在生物体内代谢产物的毒效应上。但是近期研究表明紫外光的照射对多环芳烃的毒性具有显著影响,称为ＰＡＨｓ的光致毒效应。本文介绍了多环芳烃在紫外光照射下的急性光致毒作用,致毒作用发生机理及毒性预测的数学模型,同时探讨了ＰＡＨｓ对紫外光致癌性的影响。     

水环境多环芳烃源解析研究进展

城市化和工业化给环境带来的潜在危害引起人们对环境质量的重视。污染物来源解析研究的成果为环境管理提供了有效的工具。在查阅大量文献的基础上,综述了应用于水环境尤其是沉积物中多环芳烃源解析的主要理论方法和应用模型,并初步提出了沉积物中多环芳烃源解析方法。     

四川绵阳大气多环芳烃垂直分布特征及健康风险评价

为探究四川绵阳山区与城市大气多环芳烃(PAHs)的垂直分布特征,2021年9月16日至12月31日用大气被动采样器在观雾山6个海拔高度与绵阳电视塔5个海拔高度上开展了PAHs样品采集,并对其含量与组成进行了分析。结果表明：(1)绵阳山区与城市大气中16种PAHs的平均质量浓度分别为3.38、26.59 ng/m³。大气PAHs浓度在山区基本随海拔(682～1 680 m)升高而降低,在城市则随海拔升高先降再升又再降。(2)3环PAHs质量浓度占比最高(51.1%～73.4%),占主导地位。(3)大气中PAHs的来源主要为燃煤和交通排放。(4)绵阳大气PAHs中主要毒性物质为苯并[a]蒽。城市、山区吸入导致的超额致癌风险值分别为1.55×10^-5、2.36×10^-6,且城市为山区的6.57倍。     

乌鲁木齐市大气可吸入颗粒物中多环芳烃的污染特征及来源解析

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%。     

长跑环境中颗粒物载带多环芳烃的污染特征

2005年7月至8月监测了南开大学校内及其东、西、南三校门外长跑路段处的大气总悬浮颗粒物(TSP)中16种优控多环芳烃的污染状况。GC/MS分析结果表明,晚间长跑时段中校内外多环芳烃总量为(128.74±23.50)、(417.40±204.55)ng/m3,校外约为校内的3.24倍,PAHs含量特征显示交通污染源影响显著;多环芳烃浓度与车流量呈正相关性,且怠速车辆增多也使其浓度增大;校内上午的多环芳烃总量约为晚间1.32倍,这主要受交通污染源和风速、湿度等气象条件的共同影响。     

南昌市大气PM2.5中多环芳烃的来源解析

在南昌市布设5个采样点,分别代表工业区、居住区、交通干线区、商业区以及郊区,于2007年7～8月进行大气PM2.5的采样.根据5个采样点测得的数据,通过因子分析法判断南昌市大气PM2.5中多环芳烃的主要来源,再利用多元线性回归法确定各主要来源对多环芳烃的贡献率.结果表明,南昌市多环芳烃的主要来源为车辆排放源、高温加热源、燃煤污染源,对多环芳烃的贡献率分别为37.9%、28.2%、22.0%.     

人工湿地处理系统中多环芳烃的行为

采用Oasis HLB柱固相萃取的前处理技术,以气相色谱质谱联用仪（GC/MS）的分析方法,对我国北方永定河上游黑土洼人工湿地中多环芳烃污染的特征以及分布规律进行了研究.结果表明,该湿地系统以低环数多环芳烃污染为主,其中浓度最高的是菲和蒽,未检出高环数（5环、6环）多环芳烃.通过比较进水和出水的浓度,湿地系统总体上不能有效去除进水中的多环芳烃.但是比较不同工艺单元进出水浓度,复氧、植物根系及微生物等均影响到多环芳烃的去除效果,去除率在28%～65%之间.     

多环芳烃污染土壤生物修复的强化方法

生物降解是去除环境中多环芳烃(PAHs)的重要途径，通过采取一些强化措施，如使用表面活性剂，添加营养物质和提供共代谢底物等，可显著提高PAHs降解速度和程度，为生物修复技术的成功应用提供前提。在分析中，对近年来国内外在PAHs污染土壤生物修复强化方面的研究进展进行了综述。     

蜂窝煤燃烧烟气中多环芳烃的定量研究及粒径分布特征

通过对蜂窝煤燃烧排放的烟气中多环芳烃的定量分析,研究了17种多环芳烃在烟气颗粒相和气相中的分配以及在不同粒径颗粒物上的分布特征。结果表明：在室温下燃煤排放的多环芳烃总量以在气相中存在为主,但总体毒性则主要存在于颗粒相中;多环芳烃主要分布在亚微米级颗粒上,分子量越大的多环芳烃越趋于富集在细颗粒上,因而对健康的危害就越大。     

Accumulation and distribution of polycyclic aromatic hydrocarbons in rice (Oryza sativa)

Various tissues of rice plants were sampled from a PAH contaminated site in Tianjin, China at different growth stages of the ripening period and analyzed for PAHs. PAHs were much higher in roots than in the exposed tissues. Grains and internodes accumulated much smaller amounts of PAHs than leaves, hulls or ear axes. No specific gradient trends along roots, stem, ear axes, and grains were observed, suggesting that systematic translocation among them is unlikely. Over the ripening period, PAH concentrations were increased in rice roots and decreased in most above-ground tissues. Significant correlations between PAH and lipid contents can only be observed during full mature stage. The spectra of individual PAH compounds in rice organs including roots were similar to those in air, rather than those in soil. There was also a significant correlation between bioconcentration factor (BCF, plant over air) and octanol/air partitioning coefficient (Koa).     

Spatial and temporal distribution of polycyclic aromatic hydrocarbons (PAHs) in sediments from Daya Bay, South China

The spatial and temporal distribution of polycyclic aromatic hydrocarbons (PAHs) has been investigated in Daya Bay, China. The total concentration of the 16 USEPA priority PAHs in surface sediments ranged from 42.5 to 158.2 ng/g dry weight with a mean concentration of 126.2 ng/g. The spatial distribution of PAHs was site-specific and combustion processes were the main source of PAHs in the surface sediments. Total 16 priority PAH concentration in the cores 8 and 10 ranged from 77.4 to 305.7 ng/g and from 118.1 to 319.9 ng/g respectively. The variation of the 16 PAH concentrations in both cores followed the economic development in China very well and was also influenced by input pathways. Some of the PAHs were petrogenic in core 8 while pyrolytic source was dominant in core 10. In addition, pyrolytic PAHs in both cores were mainly from the coal and/or grass and wood combustion.     

降解菌对堆肥中多环芳烃降解作用的研究

通过在堆肥中加入经过驯化的降解菌这种土壤有机污染生物修复技术 ,对堆肥中多环芳烃的浓度变化进行监测 ,从而了解降解菌对堆肥中多环芳烃的降解作用。实验结果表明 ,降解菌的加入能明显地提高多环芳烃的降解率 ,本次实验中 ,菲、芴的去除率提高了 2 5 %左右 ,芘的去除率提高了约 4 5 %。     

LAS对土壤中多环芳烃吸附行为的影响

研究了阴离子表面活性剂十二烷基苯磺酸钠（LAS）对PAHs在士壤中吸附行为的影响。结果表明，LAS改变了PAHs在土水体系中的吸附／解吸平衡，吸附态LAS可提高土壤对PAHs的吸附，而溶解态LAS则增加了PAHs的表观溶解度，这2种作用的综合结果改变了PAHs在土水体系中的吸附系数。凶此，文中用表观吸附系数来描述PAHs在土壤-水-LAS体系中的综合吸附行为。     

LAS对土壤中多环芳烃吸附行为的影响

研究了阴离子表面活性剂十二烷基苯磺酸钠(LAS)对PAHs在土壤中吸附行为的影响.结果表明,LAS改变了PAHs在土水体系中的吸附/解吸平衡,吸附态LAS可提高土壤对PAHs的吸附,而溶解态LAS则增加了PAHs的表观溶解度,这2种作用的综合结果改变了PAHs在土水体系中的吸附系数.因此,文中用表观吸附系数来描述PAHs在土壤-水-LAS体系中的综合吸附行为.     

Distribution of polycyclic aromatic hydrocarbons in urban stormwater in Queensland, Australia

This paper reports the distribution of Polycyclic Aromatic Hydrocarbons (PAHs) in wash-off in urban stormwater in Gold Coast, Australia. Runoff samples collected from residential, industrial and commercial sites were separated into a dissolved fraction (<0.45 μm), and three particulate fractions (0.45-75 μm, 75-150 μm and >150 μm). Patterns in the distribution of PAHs in the fractions were investigated using Principal Component Analysis. Regardless of the land use and particle size fraction characteristics, the presence of organic carbon plays a dominant role in the distribution of PAHs. The PAHs concentrations were also found to decrease with rainfall duration. Generally, the 1- and 2-year average recurrence interval rainfall events were associated with the majority of the PAHs and the wash-off was a source limiting process. In the context of stormwater quality mitigation, targeting the initial part of the rainfall event is the most effective treatment strategy. The implications of the study results for urban stormwater quality management are also discussed.     

Solubilization properties of polycyclic aromatic hydrocarbons by saponin, a plant-derived biosurfactant

The enhanced solubilization of polycyclic aromatic hydrocarbons (PAHs) by saponin, a plant-derived non-ionic biosurfactant, was investigated. The results indicated that the solubilization capabilities of saponin for PAHs were greater than some representative synthetic non-ionic surfactants and showed strong dependence on solution pH and ionic strength. The molar solubilization ratio (MSR) of saponin for phenanthrene was about 3-6 times of those of the synthetic non-ionic surfactants, and decreased by about 70% with the increase of solution pH from 4.0 to 8.0, but increased by approximately 1 times with NaCl concentration increased from 0.01 to 1.0 M. Heavy metal ions can enhance saponin solubilization for phenanthrene and the corresponding MSR values increased by about 25% with the presence of 0.01 M of Cd²⁺ or Zn²⁺. Saponin is more effective in enhancing PAHs solubilization than synthetic non-ionic surfactants and has potential application in removing organic pollutants from contaminated soils.     

Influence of physical factors on polycyclic aromatic hydrocarbons (PAHs) content in vegetable oils

The aim of this study was to test the hypothesis about physical factors causing a significant decrease of polycyclic aromatic hydrocarbon (PAH) compounds in foodstuffs. For this purpose, extraction of 16 PAHs (prioritised by EPA) from selected foodstuffs (rapeseed oil and sunflower oil) was carried out. The changes in PAH content in oils exposed to selected physical factors (UV radiation, temperature and time) were observed. Oils under study were exposed to two types of UV radiation: direct and indirect (through a glass plate). In both experiments, a reduction of 16 PAHs in oils was recorded but in the latter a PAH reduction was not as high. In another experiment, the temperature of oils was raised to 40, 100 and 200°C. As a result, the content of PAHs has decreased significantly. In both cases, exposure to UV radiation and high temperature resulted in the reduction of PAHs, it was strongly correlated with the duration of experiments. The results showed relatively low contamination of oil with PAHs. Only for rapeseed oil, the level of said contamination was substantially higher than laid down limits.     

Spatial and seasonal variations of polycyclic aromatic hydrocarbons in Haihe Plain, China

A dynamic fugacity model was developed to simulate the spatial and seasonal variations of PAHs in Haihe Plain, China. The calculated and measured concentrations exhibited good consistency in magnitude with deviations within a factor of 4 in air and 2 in soil. The spatial distributions of PAHs in air were mainly controlled by emission while the seasonal variations were dominated by emission and gas-particle partition. In soil, the spatial distributions of PAHs were controlled by the soil organic carbon content while the seasonal variations were insignificant. The severest soil contamination was observed in Shanxi and followed by the southwest of Hebei province. Transfer fluxes of total PAHs between air and soil were calculated. The spatial distribution of air-to-soil flux was closely related to the landcover while the soil-to-air flux changed with soil organic matter content. Monte Carlo simulation was done to evaluate the uncertainty of the estimated results in air.     

Distribution of polycyclic aromatic hydrocarbons in agricultural soils in South Korea

The content and type of polycyclic aromatic hydrocarbons (PAH) in soils from paddy fields and upland areas in South Korea were determined using gas chromatography linked to mass spectrometry (GC–MS). The distribution map of total PAH content was obtained as a contour plot using a geographical information system. The overall distribution of PAH was found to be closely related to the pollution sources, the size of city and the type of industry. The average content of total PAH in all samples was 236 μg kg⁻¹, and the range was from 23.3 to 2834 μg kg⁻¹. The highest concentrations were found in soils sampled near iron processing plants. The concentration of PAH decreased in the order fluoroanthene>benzo(b)fluoroanthene>pyrene. Special PAH compound ratios, such as phenanthrene/anthracene and fluoroanthene/pyrene, were calculated to evaluate the origin. The collected data suggested that the pyrogenic origins such as motor vehicle exhaust and heavy industry emission were the dominant source of PAH in Korean soils.