广西钦州湾近岸表层沉积物多环芳烃分布特征及生态风险评价
2014-10-21崔振昂黄向青
崔振昂 黄向青
摘要 对广西钦州近岸海域9个表层沉积物样品的多环芳烃(PAHs)含量进行分析,结果表明,研究区表层沉积物中PAHs总体含量介于1.9~44.7 ng/g,平均值为23.4 ng/g,与国内其他近岸区相比处于较低的含量水平,表明人类活动对区域环境的影响较小。LMW/HMW(低分子质量/高分子质量)和异构体比值分析表明,广西钦州湾近岸表层沉积物中PAHs可能主要来源于石油热解-燃油污染。PAHs的生态风险评价结果显示,虽然沉积物中PAHs含量对生态环境的影响较低,但一些没有最低安全值的PAHs化合物(如苯并(b)荧蒽和苯并(k)荧蒽)的存在,也可能会对区域生态环境造成不利的影响。
关键词 多环芳烃; 分布; 来源; 风险评价; 近岸沉积物
中图分类号 S181.3 文献标识码 A 文章编号 0517-6611(2014)33-11824-03
Distributions and Risk Assessment of Polycyclic Aromatic Hydrocarbons (PAHs) in Surface Sediments from Qinzhou Bay, Guangxi
CUI Zhen-ang1,2, HUANG Xiang-qing1
(1. Guangzhou Marine Geological Survey, Guangzhou, Guangdong 510760; 2. MLR Key Laboratory of Marine Mineral Resources, Guangzhou Marine Geological Survey, Guangzhou, Guangdong 51007)
Abstract The analysis of PAHs in the surface sediment of 9 sampling sites from the Qinzhou Bay offshore area shows that total PAHs concentration ranged from 1.9-44.7 ng/g, with the average of 23.4 ng/g. Compared with the PHAs in offshore sediments from the other areas in China, the concentrations of PHAs in the study area is in lower level. The ratios of LWM/HWM ( low-molecular-weight PAH/high-molecular-weight PAH) and isomer suggestted that the fuel consumption is the mainly possible sources of PAHs. Risk assessment indicated that the sediments of Qinzhou-Beihai offshore area are in the low toxicological risk of PAHs. However, the amounts of BbF and BkF in the surface sediment, which had no minimum safety value, suggested the existence of negative ecological impact in the study area.
Key words PAHs; Distribution; Source; Risk assessment; Offshore sediments
基金项目 国土资源部海底矿产资源重点实验室开放基金项目(KLMMR-2013-A-14)。
作者简介 崔振昂(1974-),男,河北枣强人,高级工程师,博士,从事近岸带海洋环境地质研究。
收稿日期 2014-10-15
多环芳烃(Polycyclic Aromatic Hydrocarbons,PAHs)是指2个或2个以上的苯环以直链状、角状或串状排列组成的有机化合物,其广泛存在于自然环境中。由于多环芳烃具有较强的致癌性和致突变性,且在环境介質中持久存在,因此在环境污染物的研究中受到广泛关注,美国环境保护署将其中16种PAHs确定为优先控制的有机污染物[1]。环境中PAHs来源主要为有机物质的热分解和燃烧,如化石燃料(煤和石油)和植物秸秆燃烧[2-4]。
多环芳烃具有低溶解性和疏水性,在水体中会被分配到非水相中(如沉积物),因此沉积物是其主要的环境归宿。……
