Smith Zacharias J, Arlinghaus Kandis M, Boyer Gregory L, Hapeman Cathleen J
Hydrology and Remote Sensing Laboratory, Agricultural Research Service, US Department of Agriculture, 10300 Baltimore Ave, Beltsville, MD 20705, USA.
Oak Ridge Institute for Science and Education (ORISE), National Ocean Service, National Oceanic and Atmospheric Administration, 331 Fort Johnson Road, Charleston, SC 29412, USA.
Mar Drugs. 2025 Jun 27;23(7):271. doi: 10.3390/md23070271.
Paralytic shellfish poisoning toxins (PSPTs) are a class of neurotoxins most known for causing illness from consuming contaminated shellfish. These toxins are also present in freshwater systems with the concern that they contaminate drinking and recreational waters. This review provides (1) a complete list of the 84+ known PSPTs and important chemical features; (2) a complete list of all environmental freshwater PSPT detections; (3) an outline of the certified PSPT methods and their inherent weaknesses; and (4) a discussion of PSPT toxicology, the weaknesses in existing data, and existing freshwater regulatory limits. We show ample evidence of production of freshwater PSPTs by cyanobacteria worldwide, but data and method uncertainties limit a proper risk assessment. One impediment is the poor understanding of freshwater PSPT profiles and lack of commercially available standards needed to identify and quantify freshwater PSPTs. Further constraints are the limitations of toxicological data derived from human and animal model exposures. Unassessed mouse toxicity data from 1978 allowed us to calculate and propose toxicity equivalency factors (TEF) for 11-hydroxysaxitoxin (11-OH STX; M2) and 11-OH dcSTX (dcM2). TEFs for the 11-OH STX epimers were calculated to be 0.4 and 0.6 for 11α-OH STX (M2α) and 11β-OH STX (M2β), while we estimate that TEFs for 11α-OH dcSTX (dcM2α) and 11β-OH dcSTX (dcM2β) congeners would be 0.16 and 0.23, respectively. Future needs for freshwater PSPTs include increasing the number of reference materials for environmental detection and toxicity evaluation, developing a better understanding of PSPT profiles and important environmental drivers, incorporating safety factors into exposure guidelines, and evaluating the accuracy of the established no-observed-adverse-effect level.
麻痹性贝类中毒毒素（PSPTs）是一类神经毒素，因食用受污染贝类导致中毒而最为人所知。这些毒素也存在于淡水系统中，令人担忧它们会污染饮用水和娱乐用水。本综述提供了：（1）84种以上已知PSPTs及其重要化学特征的完整列表；（2）所有环境淡水PSPT检测的完整列表；（3）经认证的PSPT方法及其固有弱点概述；（4）对PSPT毒理学、现有数据弱点及现有淡水监管限值的讨论。我们展示了全球范围内蓝藻产生淡水PSPTs的充分证据，但数据和方法的不确定性限制了恰当的风险评估。一个障碍是对淡水PSPTs谱了解不足，且缺乏识别和量化淡水PSPTs所需的商业可用标准。进一步的限制是源自人类和动物模型暴露的毒理学数据的局限性。1978年未经评估的小鼠毒性数据使我们能够计算并提出11-羟基石房蛤毒素（11-OH STX；M2）和11-OH dcSTX（dcM2）的毒性等效因子（TEF）。11-OH STX差向异构体的TEF计算得出，11α-OH STX（M2α）为0.4，11β-OH STX（M2β）为0.6，而我们估计11α-OH dcSTX（dcM2α）和11β-OH dcSTX（dcM2β）同系物的TEF分别为0.16和0.23。淡水PSPTs未来的需求包括增加用于环境检测和毒性评估的参考材料数量，更好地了解PSPTs谱和重要环境驱动因素，将安全因素纳入暴露指南，以及评估既定未观察到不良效应水平的准确性。
