U.S. Geological Survey, Upper Midwest Water Science Center, Mounds View, MN, USA; North Dakota State University, Environmental and Conservation Sciences Program, Fargo, ND, USA.
Civil and Environmental Engineering and Construction Department, University of Nevada - Las Vegas, Las Vegas, NV, USA.
Sci Total Environ. 2020 Sep 20;736:139515. doi: 10.1016/j.scitotenv.2020.139515. Epub 2020 May 21.
Toxic cyanobacteria are a concern worldwide because they can adversely affect humans, animals, and ecosystems. However, neurotoxins produced by freshwater cyanobacteria are understudied relative to microcystin. Thus, the objective of this critical review was to provide a comprehensive examination of the modes of action, production, fate, and occurrence of the freshwater neurotoxins anatoxin-a and saxitoxin as they relate to human, animal, and ecosystem health. Literature on freshwater anatoxin-a and saxitoxin was obtained and reviewed for both laboratory and field studies. Current (2020) research identifies as many as 41 anatoxin-a producing species and 15 saxitoxin-producing species of freshwater cyanobacteria. Field studies indicate that anatoxin-a and saxitoxin have widespread distribution, and examples are given from every continent except Antarctica. Human and animal health concerns can range from acute to chronic. However, few researchers studied chronic or sublethal effects of freshwater exposures to anatoxin-a or saxitoxin. Ecosystem health also is a concern, as the effects of toxicity may be far reaching and include consequences throughout the food web. Several gaps in knowledge were identified for anatoxin-a and saxitoxin, including triggers of production and release, environmental fate and degradation, primary and secondary exposure routes, diel variation, food web effects, effects of cyanotoxin mixtures, and sublethal health effects on individual organisms and populations. Despite the gaps, this critical review facilitates our current understanding of freshwater neurotoxins and thus can serve to `` guide future research on anatoxin-a, saxitoxin, and other cyanotoxins.
有毒蓝藻是一个全球性的关注点，因为它们会对人类、动物和生态系统造成不利影响。然而，与微囊藻毒素相比，淡水蓝藻产生的神经毒素的研究还不够充分。因此，本综述的目的是全面考察淡水神经毒素anatoxin-a 和 saxitoxin 的作用模式、产生、命运和出现，以及它们与人类、动物和生态系统健康的关系。本文对淡水 anatoxin-a 和 saxitoxin 的实验室和现场研究进行了文献检索和综述。目前（2020 年）的研究确定了多达 41 种产 anatoxin-a 的蓝藻物种和 15 种产 saxitoxin 的蓝藻物种。现场研究表明，anatoxin-a 和 saxitoxin 分布广泛，除南极洲外，各大洲都有实例。人类和动物的健康问题可能从急性到慢性不等。然而，很少有研究人员研究淡水暴露于 anatoxin-a 或 saxitoxin 的慢性或亚致死效应。生态系统健康也是一个关注点，因为毒性的影响可能是深远的，包括整个食物链的后果。研究人员确定了 anatoxin-a 和 saxitoxin 的几个知识空白，包括产生和释放的触发因素、环境命运和降解、主要和次要暴露途径、昼夜变化、食物网效应、毒素混合物的影响以及对个体生物和种群的亚致死健康影响。尽管存在差距，但本综述有助于我们当前对淡水神经毒素的理解，并可指导未来对 anatoxin-a、saxitoxin 和其他蓝藻毒素的研究。
