【作者】 曹芳；

【导师】 张前前；

【作者基本信息】 中国海洋大学 ， 分析化学， 2008， 硕士

【摘要】 持久性有机污染物(Persistent Organic Pollutants,POPs)由于其持久性、生物蓄积性、毒性及远距离迁移性等特点,成为国际社会广泛关注的热点。本文利用气相色谱-质谱联用(GC-MS)技术对青岛近海17个站位表层沉积物中两类持久性有机污染物,即16种USEPA优控多环芳烃(PAHs)及有机氯化物,包括13种多氯联苯(PCBs)和17种有机氯农药(OCPs)的含量及来源进行了较为系统地研究;同时,针对青岛近海石油污染严重的状况,对15个站位表层沉积物中的正构烷烃的含量分布及来源进行了探讨,研究结果表明:(1)美国环保署(USEPA)优控的16种多环芳烃(PAHs)在青岛近海表层沉积物中均有检出,多环芳烃总量范围在220.6 - 2150.8 ng/g dw,总量平均值的分布特征为:胶州湾内>东北近岸>西南近岸。PAHs来源诊断指数(∑LPAHs/∑HPAHs、Phen/Ant)及主成分分析(PCA)表明,石油来源和燃烧热解产生的PAHs对青岛近海表层沉积物中的PAHs总量都有贡献,对比Long等提出的沉积物生态风险评价标准及世界其他海域的多环芳烃污染状况,青岛近海的PAHs污染处于较低污染水平,整个调查海域为低生态风险区。(2)近海表层沉积物中多氯联苯(PCBs)及有机氯农药(OCPs)总量分别为:1.51-43.72 ng/g dw,1.96- 20.01ng/g dw.,总量平均值的分布特征均为西南近岸>胶州湾内>东北近岸,检出的主要污染物是低氯代PCBs(3-5氯原子取代)及β-HCH和p, p’-DDE。青岛胶州湾内及靠近黄岛工业区的表层沉积物中的PCBs主要来源于工业石化项目及生活污水排放,而其他近海站位的PCBs主要来源于大气沉降。PCBs污染水平属于轻度污染,不会对生物产生毒副作用,属于低风险生态区。17种有机氯农药除去七氯和七氯环氧化物之外均有检出,沉积物中的α-HCH较γ-HCH均存在较大丰度,说明没有林丹类的农药继续使用;(DDD+DDE)/DDTs比例均大于0.5,表明没有新的DDT类农药的输入和使用,整个调查区域内以以往使用过的DDT类农药残留为主,沉积环境为相对氧化的环境。有机氯农药类污染物含量对比世界其他范围的海域,处于相对较低水平,但DDTs类的农药对生物体可能造成潜在的负面影响。(3)近海表层沉积物中总正构烷烃含量范围为700.1-10094.9 ng/g dw(碳数分布范围在:C11-C33),总量平均值的分布特征为:西南近岸>东北近岸>胶州湾内,正构烷烃来源诊断指数和主成分分析表明,正构烷烃主要来源于石油污染。综上所述,本文针对青岛近海这一特定海域中的三类有机污染物进行了较为系统地研究,其结果有助于比较全面的了解青岛近海有机污染物的污染状况、空间分布特征、污染来源及污染物的最终环境归宿,可以为本海域环境污染控制与治理提供基础和依据。更多还原

【Abstract】 Due to their persistence, bioaccumulation, toxicity and long-term transference, the persistent organic pollutants (POPs) have become a hot-spot and received wide attention from the international society. In this study, we investigated two categories of the POPs: the 16 USEPA priority controlled polycyclic aromatic hydrocarbons (PAHs) and the organochlorinated compounds, including 13 Polychlorinated biphenyls (PCBs) and 17 organochlorinated pesticides (OCPs) from 17 surface sediments from Qingdao coastal areas by using GC-MS. In addition, since the serious pollution status of petroleum in the coastal areas, we also kept an eye on the n-alkanes investigation from 15 surface sediments. The study shows:(1) The 16 USEPA priority controlled PAHs were detected in all of the sediments and the total PAHs concentration ranges from 220.6 - 2150.8 ng/g dw,. The distribution pattern of the mean PAHs is: the stations in the Jiaozhou Bay > the stations along the northeastern coast > the stations along the southwestern coast. Both the sources index of the PAHs (∑LPAHs/∑HPAHs, Phen/Ant) and the principal component analysis (PCA) reveals that the PAHs in the study area come from the petrogenic and pyrolytic sources. Compared with the PAHs concentration from other area and based on the Sediment Quality Guidelines (SQGs) advanced by Long, the PAHs pollution in Qingdao coastal areas is relatively low and the study area belongs to the low ecological-risk district.(2) The total concentrations of PCBs and OCPs from Qingdao coastal areas are 1.51-43.72 ng/g dw and 1.96-20.01ng/g dw., respectively. The distribution pattern of the mean PCBs and OCPs is: the stations along the southwestern coast > the stations in the Jiaozhou Bay > the stations along the northeastern coast. The predominant pollutants detected are low-chlorinated PCBs (3-5 Cl) in PCBs and β-HCH and p, p’-DDE in OCPs. The PCBs detected from the stations in the Jiaozhou Bay and near the Huangdao Industry District are come from the discharge of the industrial petroleum and sewage, while the PCBs from other stations come from the atmospheric deposition. The PCBs pollution in the study area is relatively low and would not pose any adverse effect on the organisms. For the OCPs, 15 OCPs are detected in the sediments except the heptachlor and its epoxide. The ratio ofα-HCH/γ-HCH is high, indicating that there is no fresh use of lindane in this area. The ratio of (DDD+DDE)/DDTs is relatively high, showing that the there is no fresh input of DDTs and the sedimentary environment is relatively aerobic. The OCPs pollution is also relatively low compared with other area, while the DDTs may pose some adverse effect on the organisms in the definite area.(3) The total concentrations of n-alkanes in Qingdao coastal areas ranges from 700.1 -10094.9 ng/g dw (the carbon number ranges from 11-33), and the distribution pattern of the mean n-alkanes is: the stations along the southwestern coast > the stations along the northeastern coast > the stations in the Jiaozhou Bay. The sources index of the alkanes and PCA show that the alkanes primary come from the petroleum pollution.As a summary, this study poses a relatively systemic investigation on two organic pollutants (PAHs, OCs and n-alkanes) in the surface sediments from Qingdao coastal areas. The results could provide the base for the environmental pollution prevention and cure in the definite area.更多还原