象山港海水和沉积物中多环芳烃分布特征和来源研究

本文研究了象山港多环芳烃（PAHs）在沉积物-海水中的分布特征,于2017年1月对港口9个采样点的沉积物和海水中16种优先控制PAHs进行分析,采用同分异构比值法和逸度方法进行来源分析和扩散行为研究。沉积物中PAHs范围为17.51×10–9～84.41×10–9,主要为高环PAHs,处于轻度污染等级。沉积物中多环芳烃主要来自高温燃烧源。表层水体、中层水体和底层水体中PAHs范围分别为41.78～105.72 ng/L、41.51～106.34 ng/L和9.18～145.17 ng/L,主要由低环PAHs组成。表层水体中PAHs主要来源于石油泄漏和石油燃烧。利用逸度系数判断PAHs扩散行为,萘（Nap）、苊（Ace）和芴（Flo）由沉积物向海水释放;苊烯（Acy）、菲（Phe）、蒽（Ant）和芘（Pyr）在沉积物和海水中处于动态平衡;荧蒽（Flu）、苯并[a]蒽（BaA）、?（Chr）和苯并[b]荧蒽（BbF）主要从海水向沉积物扩散并富集。     

某油泥堆放场地中多环芳烃的污染及其垂向分布特征

通过采集某油田油泥堆放场地及其周边24个表层土壤样品和2个剖面土壤样品,采用超声波萃取-气相色谱/氢火焰离子化检测分析方法,对美国环境保护局(USEPA)优控的16种多环芳烃(PAHs)进行定量分析.结果表明:该研究区域的PAHs污染已较为严重,污染场地内16种PAHs的检出率为100%,w(PAHs)平均值为7 770.7 ng/g;周边土壤的16种多环芳烃的检出率为58.3%～100%,二苯并［a,h］蒽及茚并［1,2,3-cd］芘的检出率相对较低,w(PAHs)平均值为2 038.8 ng/g.研究区域内主要污染物为萘、苊、二氢苊、芴、菲、蒽、荧蒽、、芘、苯并［a］蒽和苯并［a］芘.从母体PAHs与污染物来源的关系和单组分比值可以看出,污染场地内及周边土壤的污染源是石油源和燃烧源的混合源.w(PAHs)在土壤剖面中的峰值出现在40～60及20～40 cm处,不同组分的PAHs在土壤剖面中的迁移能力表现为2～3环PAHs＞4环PAHs＞5～6环PAHs.      

典型石油化工污染场地多环芳烃土壤指导限值的获取与风险评价

尝试利用英国的污染土地暴露评价模型(CLEA模型)获取了典型石油化工污染场地中几种多环芳烃(PAHs)的土壤指导限值(SGVs),并用所得到的土壤指导限值对该场地的污染物风险进行了评价.结果表明,研究区域内萘、蒽、苯并［a］芘、苊、芴、芘的土壤指导限值分别为3.57×103,6.12×107,0.874,6.81×104,6.24×104和5.84×106　ng/g.特定场地表层土壤中萘、蒽、苊、芴、芘的实测浓度(MECs)大于其相应土壤指导限值的概率均趋于0,而苯并［a］芘的为0.225.这几种PAHs的风险从大到小依次为:苯并［a］芘萘>苊>芴>芘>蒽,说明该场地的优先控制污染物为苯并［a］芘.      

白洋淀表层沉积物中多环芳烃的含量、分布、来源及生态风险评价

研究了白洋淀表层沉积物中US EPA 16种优先控制的多环芳烃(PAHs)的分布特征和污染来源,其w(PAHs)为101.3～1 494.8 ng/g (平均值为353.0 ng/g),与国内其他的湖泊和河流相比,整体处于中等污染水平. 安州采样点沉积物中w(PAHs)最高,污染最严重;其次为小田庄、烧车淀、王家寨;污染较轻的采样点为枣林庄、光淀、圈头和端村. 在16种多环芳烃单体中,菲、荧蒽、芘、苯并［b］荧蒽所占比例较大. w(荧蒽)/w(芘)和w(菲)/w(蒽)2个比值显示, 白洋淀沉积物中多环芳烃的含量和分布受石化材料燃料、煤炭及薪柴燃烧影响较大. 风险评价表明,安州采样点表层沉积物对生物存在潜在危害,而其他采样点沉积物潜在风险处于较低水平.      

珠江三角洲地区大气气溶胶中有机污染物背景研究

选择肇庆市鼎湖山自然保护区为珠江三角洲大气气溶胶有机污染评价的区域性环境背景．研究结果表明,珠江三角洲地区大气气溶胶中优控多环芳烃背景值萘、苊、二氢苊、芴、菲、蒽、荧蒽、芘、苯并（a）蒽、、苯并（b）荧蒽、苯并（k）荧蒽、苯并（a）芘、茚并（1,2,3-cd）芘、二苯并（a,h）蒽、苯并（ghi）分别为n.d.、n.d.、tr.、0.14、tr.、0．39、0.53、0.19、1.05、1.82、1.41、0.02、2.29、0.53和2．44ng/m³,总量为10.80ng/m³,其来源主要为高等植物排放.     

广州灰霾期间颗粒态PAHs的污染特征及来源

采集广州五山和荔湾（2002-03-12～2003-06-31）PM₁₀样品,并对冬、夏两季灰霾和非灰霾期间大气颗粒物中的PAHs进行分析. 广州市灰霾期间PAHs污染程度严重,特别是冬季灰霾期. 广州市夏季灰霾期间菲、蒽、荧蒽、芘、苯并［a］蒽、、茚并［1,2,3-cd］芘、二苯并［ah］蒽和苯并［ghi］比非灰霾期间相对浓度高,而冬季灰霾期间苯并［a］荧蒽、苯并［e］芘、苯并［a］芘、、茚并［1,2,3-cd］芘、二苯并［ah］蒽和苯并［ghi］比非灰霾期间的相对浓度高. 夏季非灰霾、夏季灰霾、冬季非灰霾和冬季灰霾期间的BEQ值分别为3.5、 3.35、 1.43和13.0 ng·m^-3,与国内外各大城市相比,广州市夏季非灰霾、冬季非灰霾和夏季灰霾期间的BEQ值（平均值为2.76 ng·m^-3）在国内处于较低水平,与国外城市基本相当. 冬季灰霾期间的BEQ值在国内城市中处于较高水平,说明广州冬季灰霾对人体健康的威胁比较严重. 此外,诊断参数法研究还表明夏季PAHs主要为汽油车和柴油车的混合排放,冬季PAHs的主要来源于柴油车排放和燃煤;冬季非灰霾期间PAHs一部分来自于本地排放,另一部分可能来自北方的长距离传输.     

台州湾围塘养殖水体中多环芳烃的浓度及来源

采集台州湾6个代表性点位的围塘养殖水体表层水,分析其中15种多环芳烃(PAHs)的含量,探讨其可能的来源.结果表明,水体中总PAHs平均含量为8 309.4 ng·L-1,变化范围为5 868.7～1 5156.1 ng·L-1,PAHs的组成以2-3环为主.荧蒽/(荧蒽 芘)和茚并[1,2,3-cd]芘/(茚并[1,2,3-cd]芘 苯并[g,h,i])苝比值表明,台州湾围塘养殖水体中的多环芳烃主要来自于化石燃料的燃烧.     

广佛公路机动车排放有机污染物监测与研究

对广佛公路两侧气溶胶中有机污染物进行监测调查，发现气溶胶中具有较高含量的芴、菲、蒽、荧蒽、芘、苯并［ａ］蒽、ｑｕ、苯并［ｂ］荧蒽、苯并［ｋ］荧蒽、苯并［ａ］芘、芘并［１、２、３－ｃｄ］芘、二苯并［ａ、ｈ］蒽、苯并［ｇ、ｈ、ｉ］等。通过ＴＳＰ研究认为，主干道的机动车排放和扬尘是气溶胶的主要来源，多环芳烃从机动车排放出后在迁移扩散过程中有因质量数差异而发生分离效应。通过对比可知，该区域测点多环芳烃有机     

中国主要河流中多环芳烃生态风险的初步评价

以现有的中国主要河流中多环芳烃(PAHs)的浓度数据为基础,通过定义1个危害商,利用商值法筛选出菲、蒽、荧蒽、芘、苯并[a] 蒽、 和苯并[a]芘7种对水生生态具有潜在风险的PAHs.以河流水相中PAHs浓度数据为依据,结合毒性数据库中PAHs水相浓度对水生生物的毒性数据,用概率风险评价法分析了这7种PAHs对水生生物的生态风险.结果表明,7种筛选出的PAHs风险大小依次为：蒽>芘>苯并[a]蒽>荧蒽>苯并[a]芘>菲> .     

辽河表层沉积物多环芳烃分布、来源及生态风险评价

检测了辽河表层沉积物中16种多环芳烃的含量,含量范围为184～2260ng／g,平均值为514ng／g,与世界其他河流、河口和海岸带相比,多环芳烃污染水平相对偏低。特征化合物荧蒽／（荧蒽＋芘）与茚并[1,2,3-c,d]芘／（茚并[1,2,3-c,d]芘＋苯并[g,h,i]苝）的比值表明辽河沉积物中的多环芳烃主要来源于燃烧产物。生态风险评价表明,辽河沉积物可能存在着对生物的潜在危害,区域多环芳烃的生态风险处于较低水平。     

Effects of two sludge application on fractionation and phytotoxicity of zinc and copper in the soil

The potential harm of heavy metals is a primary concern in application of sludge to the agricultural land. A pot experiment was conducted to evaluate the effect of two sludges on fractionation of Zn and Cu in soil and their phytotoxicity to pakchoi. The loamy soil was mixed with 0%, 20%, 40%, 60% and 80% (by weight) of digested sewage sludge (SS) and composted sludge (SC). The additions of both sludges caused a significant raise in all fractions, resulting in that exchangeable (EXCH) and organic bound (OM) became predominance of Zn and organic bound Cu occupied the largest portion. There was more available amount of Zn and Cu in SS treatments than SC treatments. During the pot experiment, the concentration of Zn in EXCH, carbonate (CAR) and OM and Cu in EXCH and OM fractions decreased in all treatments, so their bioavailability reduced. Germination rate and plant biomass decreased when the addition rate was high and the best yield appeared in 20% mixtures at the harvest of pakchoi. The two sludges increased tissue contents of Zn and Cu especially in the SS treatments. Zn in pakchoi was not only in relationship to ΔEXCH and ΔCAR forms but also in ΔOM forms in the sludge-soil mixtures. Tissue content of Cu in pakchoi grown on SC-soils could not be predicted by ΔEXCH. These correlation rates between Zn and Cu accumulation in pakchoi and variation of different fractions increased with time, which might indicate that sludges represented stronger impacts on the plant in long-term land application.     

Intraspecific differences in effects of co-contamination of cadmium and

A hydroponic experiment was carried out to study intraspecific differences in the effects of different concentrations of cadmium (Cd)(0-10 mg/L) and arsenate (As(V)) (0-8 mg/L) on the growth parameters and accumulation of Cd and As in six wheat varieties Jing-9428, Duokang-1, Jingdong-11, Jing-411, Jingdong-8 and Zhongmai-8. The endpoints of wheat seedlings, including seed germination,biomass, root length and shoot height, decreased with increasing the Cd and As concentrations. Significant differences in seed germination, biomass, root length, shoot height and the accumulation of Cd and As were observed between the treatments and among the varieties (p ＜ 0.05). The lethal dosage 50% were about 20, 80, 60, 60, 80 and 20 mg As/L for Jing-9428, Duokang-1, Jingdong-11,Jing-411, Jingdong-8 and Zhongmai-8, respectively, and the corresponding values for Cd were about 30, 80, 20, 40, 60 and 10 mg Cd/L, respectively. Among the six varieties, Duokang-1 was found to be the most resistant to Cd and As toxicity, and Zhongmai-8 was the most sensitive to Cd and As co-contamination. The resistance of the six varieties was found dependant on the seedling uptake of Cd and As. Duokang-1 was the most suitable for cultivation in Cd and As co-contaminated soils.     

Toxic effects of acetochlor, methamidophos and their combination on nifH gene in soil

Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis （DGGE） and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity （both in gene richness and diversity index values） and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor （50 mg/kg） recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos （150 mg/kg） caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos （250 mg/kg） produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes （bands） responded differently to the impact of agrochemicals： four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.     

EDTA-enhanced phytoremediation of lead contaminated soil by Bidens maximowicziana

Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils.Bidens maximowicziana is a new Pb hyperaccumulator,which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb.The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues.The Pb distribution order in the B. maximowicziana was:leaf>stem>root.The effect of amendments on phytoremediation was also studied.The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application.Compared with CK(control check),EDTA application promoted translocation of Pb to overground parts of the plant.The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg.This research demonstrated that B.maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil,especially,combination with EDTA.     

Distribution and ecological effect of mercury in Laogang landfill, Shanghai, China

Laogang landfill near Shanghai is the largest landfill in China, and receives about 10000 t of daily garbage per day, Samples of topsoil and plants were analyzed to evaluate mercury pollution from the landfill. For topsoil samples, there were significant correlations among total mercury （HgT）, combinative mercury （Hgc） and gaseous mercury （HgG）, and content of total organic carbon （TOC）, but, no significantly relationship was found between Hg content and filling time. Hg content changes in vertical profiles with time showed that the average Hgv of profiles 1992, 1996, and 2000 was similar, but their average HgG was quite different. HgT was significantly correlated with Hgc in profile 1992 and 2000, and Hgv was significantly correlated with Hg6 in profile 1996. HgG/Hgv ratio in profile samples decreased in the order of （HgG,/HgT）1992〉（HgG/HgT）1996〉〉（HgG/HgT）2000. A simple outline of Hg release in landfill could be drawn： with increasing of filling time, degradation undergoes different biodegradation, accordingly, gaseous mercury goes through small, more, and small proportion to total mercury. Distribution of Hg in plants was inhomogeneous, following the order of leaf〉root〉stem. The highest value of leaf may be associated with higher atmospheric Hg from landfill. Ligneous plants （e.g. Phyllostachys glanca, Prunus salicina and Ligustrum lucidum） are capable of enriching more Hg than herbaceous plants.     

Arsenic uptake by arbuscular mycorrhizal maize （Zea mays L.） grown in an arsenic-contaminated soil with added phosphorus

The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.     

Enzymatic oxidation of aqueous pentachlorophenol

The influence of the nonionic surfactant Tween 80 on pentachlorophenol （PCP） oxidation catalyzed by horseradish peroxidase was studied. The surfactant was tested at concentrations below and above its critical micelle concentration （CMC）. Enhancement of PCP removal was observed at sub-CMCs. The presence of Tween 80 in the reaction mixture reduced enzyme inactivation which occurred through a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in the presence or absence of Tween 80. At supra-CMCs, the surfactant caused noticeable reductions in PCP removal, presumably through micelle partitioning of PCP which precluded the hydrophobic PCP molecule from interacting with the enzyme.     

Decomposition of alachlor by ozonation and its mechanism

Decomposition and corresponding mechanism of alachlor, an endocrine disruptor in water by ozonation were investigated. Results showed that alachlor could not be completely mineralized by ozone alone. Many intermediates and final products were formed during the process, including aromatic compounds, aliphatic carboxylic acids, and inorganic ions. In evoluting these products, some of them with weak polarity were qualitatively identified by GC-MS. The information of inorganic ions suggested that the dechlorination was the first and the fastest step in the ozonation of alachlor.     

Degradation of metabolites accumulated of benzo[a]pyrene by coupling Penicillium Chrysogenum with KMnO4

Several main metabolites of benzo[a]pyrene （BaP） formed by Penicillium chrysogenum, Benzo[a]pyrene-1,6-quinone （BP 1,6- quinone）, trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene （BP 7,8-diol）, 3-hydroxybenzo[a]pyrene （3-OHBP）, were identified by high-performance liquid chromatography （HPLC）. The three metabolites were liable to be accumulated and were hardly further metabolized because of their toxicity to microorganisms. However, their further degradation was essential for the complete degradation of BaP. To enhance their degradation, two methods, degradation by coupling Penicillium chrysogenum with KMnO4 and degradation only by Penicillium chrysogenum, were compared; Meanwhile, the parameters of degradation in the superior method were optimized. The results showed that （1） the method of coupling Penicillium chrysogenum with KMnO4 was better and was the first method to be used in the degradation of BaP and its metabolites; （2） the metabolite, BP 1,6-quinone was the most liable to be accumulated in pure cultures; （3） the effect of degradation was the best when the concentration of KMnO4 in the cultures was 0.01% （w/v）, concentration of the three compounds was 5 mg/L and pH was 6.2. Based on the experimental results, a novel concept with regard to the bioremediation of BaP-contaminated environment was discussed, considering the influence on environmental toxicity of the accumulated metabolites.     

Impact of atrazine and nitrogen fertilizers on the sorption of chlorotoluron in soil and model sorbents

Sorption of chlorotoluron in ammonium sulfate, urea and atrazine multi-solutes system was investigated by batch experiments. The results showed application of nitrogen fertilizers to the soil could affect the behavior of chlorotoluron. At the same concentration of N, sorption of chlorotoluron decreased as the concentration of atrazine increased on the day 0 and 6 in soil, respectively. The sorption of chlorotoluron increased from 0 to 6 d when soils were preincubated with deionized water, ammonium sulfate and urea solution for 6 d. That indicated incubation time was one of the most important factors for the sorption of chlorotoluron in nitrogen fertilizers treatments. The individual sorption isotherms of chlorotoluron in rubbery polymer and silica were strictly linear in single solute system, but there were competition sorption between pesticides or between pesticides and nitrogen fertilizers. That indicated the sorption taken place by concurrent solid-phase dissolution mechanism and sorption on the interface of water-organic matter or water-mineral matter.