胶州湾海水中阴离子表面活性剂的含量及分布

ANIONIC SURFACTANTS IN SEAWATER OF JIAOZHOU BAY

根据2003年5月和8月对胶州湾进行的两次现场调查,采用亚甲基蓝分光光度法测定了该海域海水中阴离子表面活性剂含量并初步分析了其分布特点。结果表明,2003年5月胶州湾全湾表层海水中阴离子表面活性剂平均浓度为12.6μg/L,略高于8月份(10.3μg/L);各站位含量有变化,河口及邻近海域站位高于其他站位;表层海水含量高于底层海水。

Large amounts of surfactants were discharged into ocean from industry and urban discharge everyday all over the world. Total world production of detergents is about 1.5 million tons per year; most of them were released to environment in wastewaters. Alkylbenzene sulfonates with branched alkyl chains in strong detergent were the first class of compound, responsible for the harmful environment pollution. On the other hand, some degradable detergents under aerobic conditions can yield aromatic compounds and other xenobiotics, accumulatable in the environment and hazardous to human body. Some synthetic benzene compounds are very poisonous and resistant to biodegradation, and toxic to microorganisms. Jiaozhou Bay is a semi-enclosed bay in the western part of Shandong Peninsula. The bay is surrounded by Qingdao City (population 7 mln), with an area of about 390 km2, average depth of 7m. More than 10 small rivers enter the bay, most of them carry industrial and living wastes. However, no case of surfactants pollution in Jiaozhou Bay has been reported. According to seasonal environmental monitoring in Jiaozhou Bay in May and August 2003, the content and distribution of the anionic surfactants in this area were analyzed preliminarily in this paper. The samples from 33 stations were collected during May and August 2003 along five transects, named A, B, C, D, and Y. Stations A0, A7, A6, A5 belonging to the transect A were located at Licun River mouth and its adjacent sea area; A10 was located at Dagu River mouth and Stations A1 and A11 were between Dagu and Yanghe River mouths; A2, A3, A4 neared the Hongdao wharf of the north of Jiaozhou Bay. Transects B and Y were set around Haibo River mouth and Loushan River mouth. Transects C and D were placed in sea areas neighboring Qingdao Harbor, Huangdao Ferry, and Music Square. In this study, we used methylene blue method to measure anionic surfactants. In both May and August, anionic surfactants were under the detection limit in 13 stations. In May 2003, the concentrations of anionic surfactants ranged from 5 to 122μg/L, average at 12.6μg/L, maximum at Y0. Average of Transects Y and B were higher than those of other transects. In August, the anionic surfactant concentrations were in the range of 5—93.5μg/L, was averaged at 10.3μg/L, highest at B0. Similar to in May, the anionic surfactant concentrations were in Transects Y and B. As a whole, anionic surfactants distributed mainly at eastern part of Jiaozhou Bay——Haibo, Licun, Loushan rivers mouths and their adjacent sea areas. Moreover, clear lowering concentrations were shown from river mouth to seaward direction, indicating anthropogenic inputs to the bay. In the eastern shore of Jiaozhou Bay, a large sewage disposal plant was built; however, as much as 52.35 mln-ton of sewage were let to the sea every year. Industrial and urban sewage effluents with high concentrations of anionic surfactant generally flow into the rivers then into the bay without any treatment, which was probed by the correlation between anionic surfactants and environment parameters (temperature, salinity, pH and chlorophyll a). Positive correlations were found between anionic surfactants concentration and temperature or chlorophyll a, and negative correlations to salinity or pH. Higher temperature and lower salinity near river mouth than that of inner bay, was the reason of the removal. During the two surveys, surface water and bottom water were sampled at the Stations A3, A5, C3, and D5. Results showed higher content of anionic surfactants in surface water than those of bottom water. This is because when they enter the sea, they tend to be on the surface of the water. In overall, the average content of the anionic surfactants was 12.6μg/L in May and 10.3μg/L in August 2003 surveys. Different at stations exhibited variations in the content, higher in near shore, higher in surface water and lower in bottom water.