Agrochemicals such as herbicides change the physical and chemical conditions of aquatic ecosystems and alter the community structure and dynamics of phytoplankton. Cyanobacteria are photosynthetic organisms found at the base of aquatic food chains. When cyanobacteria form blooms and produce toxins, they harm humans and the environment. Herbicides contaminate the aquatic environment when they are leached and transported via surface runoff from farms and industries. In this review, we show that these compounds have different mechanisms of action, but at high concentrations, they cause oxidative stress, interfere with the normal functioning of enzymes, and change the metabolic profile of microalgae and cyanobacteria. This paper demonstrates that at environmentally relevant concentrations, some herbicides facilitate the formation of cyanobacterial harmful algal blooms (cyanoHABs). The formation of blooms is driven by the tolerance of cyanobacteria to herbicides, where some of these compounds are degraded and converted into non-toxic forms. The degradation by-products are also used as a source of nutrients to support cyanobacterial growth. This adaptation sometimes leads to higher concentrations of bioactive compounds such as cyanotoxins in the aquatic environment. The increased levels of cyanotoxins and herbicides in water bodies can trigger a cascading toxicological effect on non-targeted organisms and the aquatic food chain. Despite the evidence confirming herbicides influence the growth of cyanobacteria and alter the structure of the phytoplankton community toward the formation of cyanoHABs, there is a lot that remains to be done to fully understand their impact on these organisms.

除草剂等农药会改变水生生态系统的物理和化学条件，并改变浮游植物的群落结构和动态。蓝细菌是在水生食物链底部发现的光合生物。当蓝细菌形式开花并产生毒素时，它们会危害人类和环境。当除草剂从农场和工业中经地表径流沥滤和运输时，会污染水生环境。在这篇综述中，我们表明这些化合物具有不同的作用机理，但是在高浓度下，它们会引起氧化应激，干扰酶的正常功能，并改变微藻类和蓝细菌的代谢特性。本文表明，在与环境相关的浓度下，一些除草剂促进了蓝藻有害藻华（cyanoHABs）的形成。蓝藻对除草剂的耐受性驱动了水华的形成，在这些除草剂中，某些化合物被降解并转化为无毒形式。降解副产物还被用作营养物质的来源，以支持蓝细菌的生长。这种适应有时会导致水生环境中生物活性化合物（例如氰毒素）的浓度更高。水体中氰毒素和除草剂水平的增加可触发对非目标生物和水生食物链的级联毒理学作用。尽管有证据表明除草剂会影响蓝细菌的生长并改变浮游植物群落的结构，从而形成蓝藻HAB，