Song Lirong, Chen Wei, Peng Liang, Wan Neng, Gan Nanqin, Zhang Xiaoming
State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072, PR China.
Water Res. 2007 Jul;41(13):2853-64. doi: 10.1016/j.watres.2007.02.013. Epub 2007 May 29.
For the purpose of understanding the environmental fate of microcystins (MCs) and the potential health risks caused by toxic cyanobacterial blooms in Lake Taihu, a systematic investigation was carried out from February 2005 to January 2006. The distribution of MCs in the water column, and toxin bioaccumulations in aquatic organisms were surveyed. The results suggested that Lake Taihu is heavily polluted during summer months by toxic cyanobacterial blooms (with a maximum biovolume of 6.7 x 10(8)cells/L) and MCs. The maximum concentration of cell-bound toxins was 1.81 mg/g (DW) and the dissolved MCs reached a maximum level of 6.69 microg/L. Dissolved MCs were always found in the entire water column at all sampling sites throughout the year. Our results emphasized the need for tracking MCs not only in the entire water column but also at the interface between water and sediment. Seasonal changes of MC concentrations in four species of hydrophytes (Eichhornic crassipes, Potamogeton maackianus, Alternanthera philoxeroides and Myriophyllum spicatum) ranged from 129 to 1317, 147 to 1534, 169 to 3945 and 124 to 956 ng/g (DW), respectively. Toxin accumulations in four aquatic species (Carassius auratus auratu, Macrobrachium nipponensis, Bellamya aeruginosa and Cristaria plicata) were also analyzed. Maximum toxin concentrations in the edible organs and non-edible visceral organs ranged from 378 to 730 and 754 to 3629 ng/g (DW), respectively. Based on field studies in Lake Taihu, risk assessments were carried out, taking into account the WHO guidelines and the tolerable daily intake (TDI) for MCs. Our findings suggest that the third largest lake in China poses serious health threats when serving as a source of drinking water and for recreational use. In addition, it is likely to be unsafe to consume aquatic species harvested in Lake Taihu due to the high-concentrations of accumulated MCs.
为了解微囊藻毒素（MCs）在环境中的归宿以及太湖有毒蓝藻水华造成的潜在健康风险，于2005年2月至2006年1月开展了一项系统调查。对水柱中MCs的分布以及水生生物体内毒素的生物积累情况进行了调查。结果表明，太湖在夏季受到有毒蓝藻水华（最大生物量为6.7×10⁸个细胞/升）和MCs的严重污染。细胞结合毒素的最大浓度为1.81毫克/克（干重），溶解态MCs的最高水平达到6.69微克/升。全年在所有采样点的整个水柱中均能检测到溶解态MCs。我们的结果强调不仅需要在整个水柱中追踪MCs，还需要在水与沉积物的界面处进行追踪。四种水生植物（凤眼莲、马来眼子菜、空心莲子草和穗花狐尾藻）中MC浓度的季节变化范围分别为129至1317、147至1534、169至3945和124至956纳克/克（干重）。还分析了四种水生生物（鲫、日本沼虾、铜锈环棱螺和褶纹冠蚌）体内毒素的积累情况。可食用器官和不可食用内脏器官中的最大毒素浓度分别为378至730和754至3629纳克/克（干重）。基于在太湖的实地研究，考虑到世界卫生组织的指导方针和MCs的每日耐受摄入量（TDI）进行了风险评估。我们的研究结果表明，中国第三大湖作为饮用水源和用于娱乐用途时会带来严重的健康威胁。此外，由于太湖中收获的水生物种积累了高浓度的MCs，食用这些物种可能不安全。
