摘要
为了解富营养化水体中鱼体内微囊藻毒素(MC)的积累水平及其分布特征,2003年4月和9月份两次在滇池试验区采集了鲢、鳙和草鱼等鱼种,用ELISA方法对鱼体中肝、肾、空肠、胆、肌肉等不同组织中MC的含量进行了检测。结果表明,MC在所有样品中均能检测到,且主要分布在鱼体的肝肾脏和消化道等器官,而肌肉和非消化道器官中毒素含量相对较低。不同鱼种不同组织对MC的富集程度也明显不同,鲢鳙中肝脏和肾脏这两个主要的靶器官对MC的蓄积能力就远高于草鱼。同时,不同季节MC在鱼体内的积累水平也明显不同,4月份鱼样中MC的含量普遍低于9月份鱼样中MC的含量。最后按照WHO生活饮用水安全标准的建议进行推算,所有鱼肉中的MC均没有超过其推荐的人体每日可允许摄入量(≤0.04μg/kg人体重),初步推断鱼肉中MC暂时还未危及到人体健康,但仍具有潜在的风险性。
The occurrence of heavy water blooms of cyanobacteria （blue-green algae, BGA） in surface water is receiving increasing attention world wide as a potential health concern. This is a serious water quality problem because many of the cyanobacterial species or strains are able to produce potent toxins. The most frequently reported cyanobacterial toxins are cyclic heptapeptide hepatotoxins, microcystins, isolated from several species of the freshwater genera Micro-cystis, Planktothrix （Oscillatoria）, Anabaena and Nostoc. They are potent and specific inhibitors of the serine threonine family of protein phosphatases, especially PP1 and PP2A. In order to minimize public exposure to MCs, the World Health Organization （WHO） has set a provisional guideline value of 1 μg/L for MC-LR in drinking water and estab-lished the tolerable daily intake （TDI） for consumption of cyanobacteria products contends MCs （0.04 μg/kg/day）. Aquatic animals could bioaccumulate microcystins（cyanobacteria hepatotoxins） and so, beyond water, the ingestion of contaminated food represents a human health risk. In order to evaluate the potential risk of their ingestion, this study was mainly investigated the residue levels and distribution features of microcystins in fish from eutrophicated Lake Dianchi, a hypertropic lake in Yunnan Province containing toxic cyanobacteria blooms all the year round. Samples of silver carp （Hypophthalmichthys molitrix）, bighead carp （Aristichthys nobilis） and grass carp （Ctenopharyngodon idellus） were collected in the biomanipulation test area in Lake Dianchi respectively in April and September, 2003. Microcystins in different tissues were all analyzed by enzyme-linked immunosorbent assay （ELISA） and the concentration was expressed as microcstin-LR equivalent. The results showed that microcystins presented in all samples, mainly distributing in liver, kidney and digestive tracts, and little in the muscle and the non-digestive tract organs. Different resi-due levels of microcystins were obviously in different fishes. Concentrations of microcystins in liver and kidney, the target organs of silver carp as well as bighead carp were significantly higher than that in grass carp. On the other hand, the residue levels of microcystins were also changeable along with seasons. Concentrations of microcystins in fish samples in April were lower than that in September. Finally, the safety assessment of the microcystin in fish muscle was also evaluated. According to the standard recommended by WHO, we calculated that the concentration of microcystins in fish muscle of all samples were not above the limit for human consumption. Then, we simply concluded that micro-cystins in fish muscle had not yet endangered to the human health only existed in the potential health risks.
出处
《水生生物学报》
CAS
CSCD
北大核心
2010年第2期388-393,共6页
Acta Hydrobiologica Sinica
基金
国家重点基础研究发展规划(973)项目(2008CB418101)
NSFC-云南联合基金(U0833604)
中国科学院重要方向项目(KZCX2-YW-426)资助
关键词
滇池
鱼体
微囊藻毒素
积累水平
分布特征
Lake Dianchi
Fish
Microcystin
Residue levels
Distribution features
