Anthropogenic eutrophication of tropical lakes usually develops harmful cyanobacterial blooms. As algal blooms spread, the frequency of appearance of cyanotoxin producing strains increases. Within the cyanotoxins, microcystins stand out to produce numerous cases of intoxications/fatalities of livestock and humans. Since 2003, some previously crystal-clear lakes of the “Lagunas de Montebello” National Park (LMNP), Chiapas, southern Mexico, have turned brilliant green associated with perennial cyanobacterial blooms. Although these lakes are used as drinking water supply, fisheries, irrigation, and tourism, the risk of cyanotoxins’ possible presence in these water bodies had not been evaluated. Therefore, this research aimed to measure the cyanobacterial biomass and identify and measure microcystins concentration in the LMNP eutrophic lakes. Phytoplankton was dominated by well-known cyanotoxins producing cyanobacteria (Planktothrix, Raphidiopsis, and Limnothrix). Microcystins in LMNP lakes were confirmed, while the microcystin concentration ranged from 2.0 to 5.3 µg L⁻¹. This range indicates a relatively low probability of causing acute health effects through human consumption or recreational purposes. However, these results compel the necessity of implementing a follow-up program (nonexistent in the LMNP management plan) to measure microcystins and the whole range of cyanotoxins along an annual cycle to be able to recognize the toxins’ maximum concentrations and their potential bioaccumulation in the food web. It is also needed to investigate more accurately the seasonal phytoplankton dynamics together with all limnological parameters.

热带湖泊的人为富营养化通常会产生有害的蓝藻水华。随着藻华的扩散，产生蓝藻毒素菌株的出现频率增加。在蓝藻毒素中，微囊藻毒素引人注目，可引起许多牲畜和人类中毒/致命的事件。自2003年以来，墨西哥南部恰帕斯州“ Lagunas de Montebello”国家公园（LMNP）的一些先前水晶般清澈的湖泊已变成与常年存在的蓝藻水华有关的鲜绿色。尽管这些湖泊被用作饮用水，渔业，灌溉和旅游业，但尚未评估这些水体中可能存在氰毒素的风险。因此，本研究旨在测量蓝藻生物量并鉴定和测量LMNP富营养化湖泊中微囊藻毒素的浓度。Planktothrix，Raphidiopsis和Limnothrix）。证实了LMNP湖泊中的微囊藻毒素，而微囊藻毒素的浓度范围为2.0至5.3 µg L ^-1。该范围表明通过人类食用或娱乐目的引起急性健康影响的可能性相对较低。但是，这些结果迫使有必要实施一项后续计划（LMNP管理计划中不存在），以测量一个年度周期内的微囊藻毒素和全部范围的蓝藻毒素，以便能够识别出该毒素的最大浓度及其潜在的生物蓄积性。食物网。还需要更准确地调查季节性浮游植物的动态以及所有的气候学参数。