中文摘要：

研究了巨牡蛎（Crassostrea sp.）对配备烟气海水脱硫装置电厂的脱硫海水中汞（Hg）的生物累积.在电厂的排水口（实验点）和参考点分别吊养牡蛎群,定期采集样品,测定海水中的Hg浓度和牡蛎的Hg含量（均以干重计）.实验点和参考点海水中的总汞（THg）浓度分别为（120.6±55.5）ng.L-1（n=5）和（2.7±1.0）ng.L-1（n=5）,甲基汞（MeHg）的浓度分别为（0.30±0.44）ng.L-1（n=5）和（0.28±0.31）ng.L-1（n=5）.在7 d内,实验点牡蛎体内THg含量从（138.3±14.3）ng.g-1（n=6）迅速增加到（3 012±289）ng.g-1（n=6）,且在后来的34 d内,一直保持在2 935～4 490 ng.g-1的高含量水平;而参考点牡蛎对THg未见明显累积,为60.7～137.5 ng.g-1之间.暴露期间实验点牡蛎体内MeHg的含量未发生显著变化,保持在55.4～73.1 ng.g-1之间.而参考点牡蛎MeHg含量呈略微下降的趋势,但变化幅度不大,在15.6～55.6 ng.g-1之间.本研究表明,燃煤电厂排放的脱硫海水中的THg可被牡蛎迅速累积至很高的含量水平,有不容忽视的潜在风险.脱硫海水中MeHg的浓度很低,其在牡蛎体内未见明显累积;在本研究的条件下,未观测到牡蛎自身合成MeHg或将无机汞转化为MeHg.

英文摘要：

A field experiment was conducted to study mercury（Hg） bioaccumulation in Crassostrea sp.exposed to waste seawater discharged from a coal-fired power plant equipped with a flue gas desulfurization system.Oysters were cultured in the discharge outlet of the power plant（studying site） and a control site,respectively.The total Hg（THg） concentrations（all counted as dry weight） of seawater in the studying and control sites were determined as（120.6±55.5）ng·L-1（n=5） and（2.7±1.0）ng·L-1（n=5）,respectively,while methyl Hg（MeHg） concentrations were（0.30±0.44）ng·L-1（n=5） and（0.28±0.31）ng·L-1（n=5）,respectively.The THg in oyster at the studying site increased dramatically from（138.3±14.3）ng·g-1（n=6） to（3 012±289）ng·g-1（n=6） within 7 d,and remained at high levels of 2 935-4 490 ng·g-1 for the next 34 d.In contrast,the THg in oyster at the control site showed no significant change,and kept at low levels of 60.7-137.5 ng·g-1.After 41 d exposure,the MeHg in oyster at the studying site had no significant change,ranging from 55.4 ng·g-1 to 73.1 ng·g-1,and the content at the control site showed a slight decrease,ranging from 15.6 to 55.6 ng·g-1.The study showed that THg in the waste seawater discharged at the coal-fired power plant could be quickly bioaccumulated by oyster to a great extent,the potential risk can thus not be ignored.MeHg concentration in the waste seawater was quite low,and no obvious bioaccumulation was found in oyster.Under the study conditions,no self-synthesis of MeHg or transformation of inorganic Hg into MeHg was found.