我国藻毒素不同种类和结构的协同毒性机制及生态风险评价研究

The toxic red tide disaster is becoming increasingly, and toxic algae produce toxins which can serious damage humans and other animals,which having serious damaged development of national economy,marine ecological environment and human’s health of maritime countries. A variety of phycotoxins have been reported in China.Types and structures and toxicological ecology of algal toxins are very complex, toxicological mechanism of various algae toxin is not clear, and little is known about the ecological harm. In this study, the toxicological mechanism of phycotoxins will studied using cell and animal toxicity, enzyme activity and physiological function, and RAPD-PCR analysis techniques; the content and distribution of microalgal toxins in water, sediment, plankton, shellfish and fish, and other organisms species will analyzed by HPLC-MS/MS technique; average and allow food intake, acute and chronic exposure mode, no effects of concentration, growth, reproduction, the species abundance and diversity will be tested, and ecological risk will be assessed by using an assessment factor method and species sensitivity distribution curve method, multi species testing method and the model of ecological risk assessment. There is an urgent need for the study of synergistic toxicity mechanism of types and structure of microalgae toxins in China, and put forward related safety threshold, and study on method of establishing the model of risk assessment, and assess ecological risk of Chinese existing phycotoxins, especially for the risk of long-term and lower dose, and provide scientific basis to formulate relevant policies and regulations for the government, to protect the ecological environment, to maintain the marine economy sustainable development, and to protect the health of people.

有毒赤潮灾害日益严重，有毒微藻分泌毒素，严重损害沿海国家的经济、生态环境和人类健康。我国存在多种微藻毒素。藻毒素种类结构、毒理生态学复杂多样，多种藻毒素的毒理机制尚不清楚，生态危害知之甚少。本研究用细胞和动物毒性、酶活性和生理功能、RAPD-PCR等技术研究藻毒素的复合毒理机制；用HPLC-MS/MS技术分析藻毒素含量，确定藻毒素在沉积物、水体、贝鱼和浮游生物中的种类结构分布和时空、区域变化规律；研究平均和允许摄食量、急性和慢性暴露模式、无效应浓度、生长抑制、繁殖能力、物种丰度和多样性水平等因子，用评估因子法和物种敏感度分布曲线法、多物种测试法和生态风险模型法评估风险；针对我国存在藻毒素种类结构的复合毒性，确定相关的安全阈值，研究我国藻毒素风险评价技术模型，评价我国现存藻毒素的生态风险，特别是长期、低剂量、复合毒性的风险，为制定政策法规、发展经济、保护生态环境和人们健康提供科学依据。

有毒赤潮增加，有毒微藻产生毒素，毒害食用者，改变海洋生态系统结构，具有生态风险。我国分布多种产毒微藻，发现微藻毒素，相关研究薄弱、空白。研究了有毒微藻、藻毒素对海洋生物的协同、毒性机制；高通量测序研究对细菌群落多样性的影响，转录组分析对浮游生物基因组成效应；调研有毒赤潮藻的种类分布；明确藻毒素在各类海产生物中的种类结构；商值法评价健康风险；物种敏感度曲线法评估物种生态安全阈值，联合概率模型评估示范区三种有毒微藻的生态风险。.结果揭示，微藻毒素OA、DTX1、PTX2、YTX、homo-YTX、SPX1、GYM、AZA1、AZA2、AZA3、PbTX-2、PbTx-3、STX、dcSTX对卤虫、青鳉鱼、水蚤、微藻等具有不同急性毒性。AZA1毒性最大（96h LD50=6.081）；网状原角藻、利玛原甲藻、微小亚历山大藻、腹孔环胺藻对卤虫、青鳉鱼、金藻、大扁藻、海链藻具有毒性，网状原角藻对伪矮海链藻毒性最大（96h-EC50为100cell/mL）；几种微藻毒素对浮游动物具有协同毒性作用，显示强者恒强的规律；有毒微藻细胞比纯毒素毒性更大；毒藻对细菌群落多样性、浮游生物基因具有毒性效应，利玛原甲藻多样性指数最低；我国海域175种生物中发现7种、16结构微藻毒素，北黄海栉孔扇贝含8.1mg/kg的软海绵酸毒素，在螺、腔肠动物、鱼、棘皮动物等都发现了微藻毒素，大泷六线鱼（含Pbtx-2达2450µg/kg）、光棘球海胆（YTXs为2400µg/kg）、刀额新对虾（DA为2080µg/kg）、三疣梭子蟹（Pbtx-3为862µg/kg）等发现了高含量的微藻毒素；我国海域16种有毒赤潮藻被记录，北黄海CH海域的网状原角藻、塔玛亚历山大藻，利玛原甲藻在CH和MJK被检出；我国贝类某些藻毒素健康风险高；示范海区95%物种安全性高，个别站位局部水域高发种类的生态风险严重。.本基金首次系统研究了7类（21种结构）微藻毒素、4种产毒藻对海洋生物的毒性，为推荐我国海产品限量值及生态安全阈值奠定了理论基础；首次系统调研了我国175种海洋生物的藻毒素分布特征，为全面评估藻毒素现状和健康风险提供依据；首次应用物种敏感度分布法评估有毒微藻的生态风险，为全面评价生态效应奠定技术方法。