Nutrient over-enrichment in freshwater environments, together with the on-going climate change, favour the toxin-producing cyanobacteria bloom. Human health hazard may arise from drinking contaminated water. Additionally, cyanobacterial blooms affect other economic areas such as tourism, recreation, commercial fishery, water management and monitoring. Nowadays there is a scarcity of information on seasonal variations of cyanotoxins in various regions. Understanding of historical trends and seasonal variation patters is a foundation for forecasting and will help to develop effective water management strategies.

This review gives an overview of cyanotoxins' analysis and levels in freshwater environments with particular emphasis on seasonal variations in Europe. Recent analytical approaches are discussed and the seasonal patterns for three major European climate zones (Mediterranean, continental, and Atlantic) were distinguished. Additionally, data from multi-year studies showed a tendency of increasing cyanotoxins' levels.

淡水环境中的养分过度富集，以及持续的气候变化，都有利于产生毒素的蓝细菌繁殖。喝受污染的水可能对人体健康造成危害。此外，蓝藻水华会影响其他经济领域，例如旅游，娱乐，商业渔业，水管理和监测。如今，缺乏有关各地区蓝藻毒素季节性变化的信息。了解历史趋势和季节性变化规律是进行预测的基础，将有助于制定有效的水资源管理策略。

这篇综述概述了藻毒素在淡水环境中的分析和含量，特别强调了欧洲的季节性变化。讨论了最近的分析方法，并区分了欧洲三个主要气候区（地中海，大陆和大西洋）的季节模式。此外，来自多年研究的数据显示出氰毒素水平升高的趋势。