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1.
本文表征了三峡库区典型次级支流(梁滩河)表层沉积物中18种多环芳烃(PAHs)的浓度,并对其分布特征和污染来源进行了探讨。18种PAHs的总浓度(∑18 PAHs)范围为198.5~4349 ng/g-dw(干重),平均浓度为1441ng/g,中值为1160 ng/g。与其他地区沉积物污染情况相比,梁滩河沉积物中PAHs浓度处于中等偏低的污染程度,支流污染程显著高于干流,流经城镇的右支污染程度显著高于流经农村或人口较少的左支和主干流。大部分采样点以高环(4~6环)PAHs污染为主。PAHs源解析结果表明,梁滩河表层沉积物中PAHs污染以燃烧源为主,主要源于化石燃料和生物质的不完全燃烧。沉积物中苯并[a]芘的毒性当量因子(TEF)值为39.38~384.37 ngTEQ/g,平均值110.94 ngTEQ/g。生态风险评价的结果表明,右支流的两个采样点R3和R4点沉积物中PAHs可能存在生物负效应影响,R4点的高风险可能与附近白市驿机场污染有关。 相似文献
2.
《中国环境管理干部学院学报》2017,(4)
建立了一种在线富集-液相色谱法检测水体中多环芳烃的方法,通过优化色谱条件,可不经萃取浓缩直接上机检测水样,取样体积仅为2.5 ml。除苊烯不能用荧光检测器检测外,其余15种多环芳烃的加标回收率为70.24%(苊)~117.25%(二苯并(a,h)蒽),相对标准偏差(n=5)在1.70%()~11.21%(茚并(1,2,3-c,d)芘)之间,检出限在1.51 ng/L(苯并(k)荧蒽)~44.4 ng/L(茚并(1,2,3-c,d)芘)之间,基本满足痕量分析要求。利用该方法测定实际样品中多环芳烃的浓度为0.053 ng/L(苊)~2.751 ng/L(芴)。 相似文献
3.
杨萌 《环境保护与循环经济》2020,40(1):64-68,80
通过对大连市工业区、居民区和城市背景区3种类型区域连续7个月大气样品的采集,分析PAHs在大气中的污染特征,并对其毒性进行评价。结果显示,城市工业区大气中PAHs含量最高,其次是居民区,城市背景区最低。3种类型采样点大气中PAHs的组成相似,菲是含量最多的物质,其次是荧蒽、芴和芘。16种PAHs基于苯并[a]芘的总毒性当量浓度为:工业区5.1 ng/m^3;居民区3.6 ng/m^3;城市背景区4.6 ng/m^3。3种类型功能区大气中PAHs的TEQ值都高于我国的《空气质量标准》(GB 3095-2012)中规定的大气中苯并[a]芘的年平均浓度(1 ng/m^3)或24 h平均浓度(2.5 ng/m^3)。 相似文献
4.
为了解西溪湿地底泥质量现状,2012年9月采集保护区内不同干扰类型的底泥样本,测试了底泥中重金属和POPs中PCBs、OCPs和PAHs的含量,并对湿地底泥污染进行了生态风险初步评价。结果表明,底泥中未检出PCBs和OCPs,但检测出14种EPA优控PAHs,总PAHs的浓度范围为115.9~217.8 ng·g^-1,低于潜在生态风险的效应区间低值ERL,其中列入中国"水中优先控制污染黑名单"的7种PAHs均有检出并且其总量占∑PAHs 1/2左右(平均为50.08%);底泥中8种重金属含量平均值低于《土壤环境质量标准》(GB 15618—1995)的二级标准,但Hg、Zn、Pb、Ni含量在多个位点已超过一级标准;分别采用土壤背景值和国家一级标准为参比值对湿地底泥中重金属进行单因子污染风险指数评价,发现分别有7种和4种元素的污染指数大于1;综合分析不同干扰类型的底泥质量,发现底泥疏浚能有效降低有机质含量、全氮和PAHs含量,但对全磷、重金属含量则无明显效果,封闭水体的干塘措施能显著减少污泥量和有机物含量。研究结果表明,西溪湿地底泥中高环PAHs和重金属污染水平可能对西溪湿地生物具有潜在的生物毒性作用及不利的生态影响效应,其疏浚底泥农用则无生态风险。 相似文献
5.
应用高效液相色谱-串联质谱(HPLC-MS/MS)联用的技术,建立了水体中磺胺类抗生素的检测方法。选用电喷雾离子源(ESI),在正离子模式下对目标化合物进行选择性反应检测(SRM)扫描。采用固相萃取法对样品进行前处理,通过HLB小柱对样品进行富集和净化。液相色谱选用C18柱,以甲醇和0.1%甲酸作为流动相对样品进行梯度洗脱分离。方法的回收率为53.6%~96.2%。方法的最低检出限除磺胺噻唑(STZ)为0.3 ng/L外,其余均为0.1 ng/L,本方法的RSD为4.7%~9.3%,该方法适用于水体中磺胺类抗生素的残留检测。 相似文献
6.
采用快速溶剂萃取、固相萃取小柱净化、气相色谱-质谱法测定土壤中16种多环芳烃的分析方法,同时比较了内标法与外标法两种定量方法。结果表明,进样口温度为310℃时,多环芳烃响应值最大。外标法中16种PAHs在10~500μg/L浓度范围内线性良好,相关系数均大于0.995,测定方法检出限为1.46~6.90μg/kg;内标法,相对响应因子相对标准偏差(RSD)小于20%,16种PAHs的方法检出限为0.10~0.32μg/kg,两种定量方法测定标准样品结果均在标准质控范围,符合质量控制要求。同时,经t检验,部分项目有显著性差异。由于外标法受干扰因素较大,因此建议使用内标法定量,该方法重现性和稳定性较好,适用于土壤中PAHs的准确测定。 相似文献
7.
低温捕集/热解吸气相色谱法分析废气中挥发性硫化物 总被引:1,自引:0,他引:1
采用低温捕集/热解吸/火焰光度检测填充柱气相色谱法可分析废气中挥发性硫化物。标准气浓度为2.80g/L~38.10g/L时,硫化氢、甲硫醇、乙硫醇、甲硫醚和二甲二硫的平均回收率及相对标准偏差分别为92.1%~106.8%及0.5%~6.0%,采样体积为1.0L时,上述挥发性硫化物的最低检出浓度为0.08ng/L~0.65ng/L。该分析测定了炼油厂某些污染源和催化燃烧脱硫中试装置废气中挥发性硫化物组成,验证了方法的适用性。 相似文献
8.
采用垂直流人工湿地模拟装置对新疆油田外排含盐稠油废水进行了处理。实验表明:对于进水CODCr为402~406mg/L,盐度5701~5712mg/L,石油类40.62mg/L的含盐稠油废水,该系统的出水指标为CODCr35~38mg/L,盐度1535~1542mg/L,湿地系统对CODCr和盐分的去除率达到91%和73%;当水力停留时间为11d以上,出水石油类<5mg/L,处理后出水CODCr、石油类达到《污水综合排放标准》(GB8978-1996)的一级标准。 相似文献
9.
采用液相萃取-HPLC-PDA-FLD法对北京市西南郊2016年2月~2017年1月采集的每个月的降水进行测定,对其每个月的PAHs含量变化、结构特征进行分析,对降水中的PAHs的来源进行解析.结果显示:北京市西南郊降水中PAHs呈现出冬季高,春秋低,夏季极少的规律.降水中PAHs的结构主要以3、4环为主.通过比值法分... 相似文献
10.
为探讨大气降尘中多环芳烃的污染水平和来源的解析,于2008年冬、春、夏、秋四个季节采集了北京昌平地区大气降尘样品,采用超声抽提方法,使用GC/MS测定了样品中PAHs的含量。结果表明,冬、春、夏、秋四个季节样品中多环芳烃总量分别为18.6μg/g、17.3μg/g、15.1μg/g和11.0μg/g,单体化合物均值分别为1.04μg/g、0.96μg/g、0.84μg/g和0.61μg/g。与其他城市监测结果比较可知:昌平地区大气降尘中PAHs含量相对较低。使用多种方法对降尘中的PAHs来源进行解析,结果表明:化石燃料燃烧在不同季节中的贡献相对稳定,燃煤在冬季为多环芳烃主要来源之一,在其他季节贡献相对较低。 相似文献
11.
The survey of polycyclic aromatic hydrocarbons (PAHs) and their relation to potential pollution sources were investigated
in suspended particulate matter (SPM), surface waters, and sediments from Elelenwo Creek, southern Nigeria. Total PAH concentrations
varied from 2,021.35 to 3,926.84 μg/kg dry weights in SPM and from 4,238.00 to 5,490.84 μg/kg dry weights in sediments. Furthermore,
concentration levels of PAHs varied from 720.46 to 857.65 μg/l in the surface waters, which indicates that the aquatic ecosystem
is polluted by PAHs. The 2, 3-ring PAHs were not dominant in SPM (34.73%), surface water (40.09%), and sediments (22.43%).
While anthracene was more abundant, of the 2, 3-ring PAHs in SPM, the most abundant in the surface waters and sediments were
fluorene and acenaphthylene. Four origin indices or concentration ratios of PAH isomer pairs were used to evaluate the suitability
of these compounds as tracers to distinguish between the contamination arising from different sources. A critical appraisal
of the PAH indices, therefore, suggested that biomass combustion is the major PAH source in the environmental matrices. Relative
PAH patterns in the environmental matrices were also evaluated using principal component analysis, and were found to correlate
with the PAH patterns of the different potential contamination sources. 相似文献
12.
Thirty-three air samples were collected by high-volume samplers from May 2007 to June 2008 in the coastal area of southwest Taiwan and analyzed for total suspended particulates (TSP) and polycyclic aromatic hydrocarbons (PAHs). Concentrations of TSP and total PAHs ranged from 40.4 to 251 μg m(-3) and 1.86-56.4 ng m(-3), respectively. Except for joss paper burning during the religious celebration of Ghost Month, which resulted in the highest concentration of PAHs in the summer of 2007, a seasonal variation in total PAH concentration was observed over this study period, with the highest concentrations in winter and the lowest in summer. Because of the geographical and climatic characteristics of the sampling site, monsoon activities modulate the seasonal variations of PAHs. Diagnostic ratios showed that PAHs in the atmosphere of the Kaohsiung coastal area arose predominantly from vehicle emissions (mainly from diesel exhaust), joss paper burning, and coal/wood combustion. The results of hierarchical cluster analysis (HCA) and principal component analysis (PCA) indicated that the sampling days could be divided into three groups and that the major source identification of PAHs was the same as the identification by diagnostic ratios. In addition, the results of HCA and PCA suggest that the samples collected with a prevailing northerly or northeasterly wind direction contain both local emissions and those from neighboring sources. On the other hand, the cases related to westerly or northwesterly winds indicated that local emission was the major source for the sampling site. 相似文献
13.
SPE-HPLC/MS联用法测定地表水中的PFOA及PFOS含量 总被引:29,自引:0,他引:29
本文建立了固相萃取与高效液相色谱/质谱(HPLC/MS)联用的方法来测定地表水中全氟辛酸(PFOA)及全氟辛烷基磺酸(PFOS)的含量。此方法中PFOA在水样中的线性范围为40ng/L到500ng/L,线性相关系数0.9986,PFOS在水样中的线性范围为5n异/L到500ng/L,线性相关系数0.9905。此方法中全氟辛酸及全氟辛烷基磺酸的平均回收率分另13为83.91%和86.63%。水样中全氟辛酸和全氟辛炕基磺酸的检出限均为0.5ng/L。方法准确、可靠,分析结果令人满意。采用此方法测定了上海部分地区地表水中全氟辛酸及全氟辛烷基磺酸的含量。实验结果表明,上海地区长江入海口处徐六泾段全氟辛酸的平均浓度是46.88ng/L,全氟辛烷基磺酸未检出;黄浦江段全氟辛酸及全氟辛烷基磺酸的平均浓度分别是1594.83ng/L(前处理后需稀释10倍以确保在方法线性范围内)和20.46ng/L。可见长江及黄浦江流域的全氟辛酸及全氟辛烷基磺酸的控制与治理亟待提上议程。 相似文献
14.
Application of Eichhornia crassipes and Pistia stratiotes for treatment of urban sewage in Israel 总被引:1,自引:0,他引:1
The effectiveness of sewage purification by aquatic plants, such as water hyacinth (Eichhornia crassipes) and water lettuce (Pistia stratiotes), was tested on laboratory and pilot scales. Cascade and semi-continuous pilot experiments verified that the plants are capable of decreasing all tested indicators of water quality to levels that permit the use of the purified water for irrigation of tree crops. This applies to biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), and turbidity. The laboratory-scale tests confirm the capacity of the plants to reach and hold reasonably low levels of BOD (5-7 mg L(-1)) and COD (40-50 mg L(-1)) and very low levels of TSS (3-5 mg L(-1)) and turbidity (1-2 NTU). In the experimental pilot setup, with circulation, COD decreased from 460 to 100 mg L(-1) after 2.5-4 days of treatment, while 6-7 days were required to this end without circulation. This doubled the active pond area and provided a two-level hydraulic loading (8 and 12 L min(-1)) with circulation that proved to be effective during the summer as well as the winter season. The outflow concentrations were 50-85 mg L(-1) of COD and 4-6 mg L(-1) of BOD. The results show that the use of this free water surface flow system (FWS) and its low maintenance system for treatment of urban and agricultural sewage is a viable option. 相似文献
15.
16.
Environmental assessment of mercury dispersion, transformation and bioavailability in the Lake Victoria Goldfields, Tanzania 总被引:2,自引:0,他引:2
Environmental dispersion and transformation of mercury discharged from gold mining operations has been investigated in field and laboratory studies in order to provide better understanding of the degree of mercury (Hg) pollution and bioavailability in the Lake Victoria goldfields (LVGF) ecosystems. This paper reviews results already published elsewhere and presents additional data on Hg dynamics in the LVGF. Studies conducted at the Mugusu and Rwamagaza artisanal mines indicated different degrees of Hg contamination and dispersion in environmental matrices. Mercury concentration in contaminated river sediments near the Mugusu mine varied from 6.0 to 0.5 mg/kg on a dry weight basis. The highest Hg contamination levels (165-232 mg/kg) were associated with mine tailings at the Rwamagaza mine. Mercury concentrations in fish representing different dietary habits on the southwestern shore of Lake Victoria at the Nungwe Bay were very low (2-35 microg/kg) and thought to represent background levels. These and other results suggested that the use of Hg in gold extraction in the LVGF has not caused high Hg levels in lake fish. The study of Hg in lichens showed Parmelia lichen to be an effective bioindicator for atmospheric Hg contamination due to Hg emissions from gold-amalgam firing and purification operations. The Hg levels in the lichens around the Mugusu mine ranged from 3.1 to 0.1 microg/g; the highest levels were recorded in the lichens sampled close to gold-amalgam processing sites. The regional background level in the Parmelia lichen was 0.05-0.10 microg/g, with a mean level of 0.07 microg/g. Studies of Hg transformation in the mine tailings revealed unexpectedly high methylmercury (MeHg) levels in the tailings (629-710 ng/g), which indicated that oxidation and methylation of metallic Hg in the tailings occurred at significant levels under tropical conditions. Re-equilibration of the tailings with freshwater (FW) indicated the MeHg was firmly bound in the tailings and therefore very little MeHg was released to the water column (0.2-1.5 ng/L). The methylation of Hg in tropical loamy clay soil contaminated with HgCl(2) (5 mg Hg/kg) yielded MeHg concentrations of 11 and 14 ng/g when inundated with seawater and FW, respectively, for 4 weeks. Little MeHg was transferred from the soil to the equilibrated water (< or = 0.4 ng/L). Atmospheric exposure of the soil pre-inundated with FW resulted in net degradation of MeHg during the 1st week of exposure, followed by net production and accumulation of MeHg in the soil (up to 15.5 ng/g) during atmospheric desiccation. Mercury uptake by fish from the Hg(0)-contaminated aquatic sediment-tailings system in the aquarium experiment was found to be low, suggesting the low availability of MeHg for bioaccumulation in the system. These and other results provide useful insights into Hg transformation, mobility and bioavailability in tropical aquatic systems affected by Hg pollution from gold mining operations. 相似文献
17.
在实验室及中试条件下研究了臭氧-活性炭技术对石油微污染地下水的处理效果。通过石油类和高锰酸盐指数两个指标,考察了臭氧投加量、pH值、过滤速率等操作参数对污染物的去除效果。结果表明:臭氧投加量和活性炭过滤速率是最主要的影响因素,pH值对处理效果影响不显著。中试条件下适宜的臭氧投加量应为8mg/L左右,最佳过滤速率在10m/h附近。采用臭氧氧化与活性炭过滤组合工艺,当进水石油类浓度在1.5mg/L以下时,出水石油类低于0.3mg/L,高锰酸盐指数低于3.0mg/L。 相似文献