机构地区: 西南大学化学化工学院
出 处: 《农业环境科学学报》 2010年第2期357-362,共6页
摘 要: 为了了解北江沉积物中汞污染现状、来源并评价其污染程度,在北江流域共采集19个沉积物样,用原子吸收法(AAS)和冷原子荧光法(CVAFS)分别测定了其总汞(THg)和甲基汞(MeHg)含量,比较了甲基化率,并用污染指数法对测定结果进行了评价。结果表明,北江沉积物THg含量为73.7~3517ng·g-(1干重),均值为607.6ng·g-1,MeHg含量为0.392~2.384ng·g-1,均值为1.302ng·g-1,韶关冶炼厂为重要污染点源。各采样点甲基化率差异较大,进一步研究影响甲基化的因素具有重要意义。沉积物中THg、MeHg平均污染指数分别为3.04、26.04,表明均为中度污染。 Mercury in environment has become the major concern in recent years due to its highly toxic to human and biota. In this study, nineteen sediment samples were collected along the Beijiang River to examine concentrations and sources of mercury, as well as methylmercury. Also, the pollution levels of mercury and its compound were assessed based on comparison with other studies. Total mercury (THg) and methylmercury (MeHg) were determined by atomic absorption spectroscopy (AAS) and cold vapor atomic fluorescence spectrometers (CVAFS), respectively. Furthermore, methylation rates were calctdated for all samples and pollution degrees of mercury in sediment were evaluated using pollution index methods. The results showed that THg concentrations in sediments ranged from 73.7 to 3 517 ng·g^-1 dry weight, with an average of 607.6 ng·g^-1, and MeHg concentrations ranged from 0.392 to 2.384 ng·g^-1 dry weight, with an average of 1.302 ng·g^-1, respectively. Clearly, wastewater from Shaoguan smelting factory was an important point source for mercury in sediment. In addition, methylation rates varied significantly among samples, suggesting that factors influencing methylation is still unclear. Thus, more studies are needed to explore the relationships between these important factors and methylation rates of mercury in sediment. Based on the average pollution index of THg(F=3.04 ) and MeHg(F=26.04) in sediment, the Beijiang River suffered from medium pollution of THg and MeHg.
领 域: [环境科学与工程]