Toxicity of glyphosate and its degradation products in aquatic ecosystems: a review

Context: The intensifying utilization of glyphosate has provoked global scientific concern due to the potential large-scale impact on ecosystems. In 2015, the International Agency for Research on Cancer (IARC) reclassified glyphosate and its degradation byproduct, aminomethylphosphonic acid (AMPA), as Category 2A, indicating probable human carcinogenicity. Knowledge Gap: A review of the existing literature reveals a relative scarcity of information on the aquatic impact of glyphosate and its degradation products. Purpose: To determine the scope and implications of the impact of glyphosate and its degradation products on aquatic ecosystems, in order to better understand their ecotoxicological effects and provide a foundation for future research and policy decisions in this area. Methodology: A systematic review of ecotoxicological studies published in Spanish and English over the last 12 years was conducted to assess the effects of glyphosate and its degradation products on aquatic ecosystems and the risks to various species. Approximately 95 documents were reviewed, including data from 69, addressing toxicity, biodegradation, contamination, and international regulations. Results: Studies have shown that chronic exposure to glyphosate can alter the metabolism in fish and affect the life cycle of organisms such as Daphnia Magna. The composition of glyphosate, along with its adjuvants, can increase its toxicity and pose risks to the aquatic ecosystem, making it crucial to understand the specific formulations and their concentrations. Conclusions: The increased use of glyphosate raised global scientific concerns due to its potential impact on ecosystems, with the IARC classifying it as possibly carcinogenic to humans. Studies showed acute toxicity to aquatic organisms and highlighted the need for risk assessment methodologies for long-term impacts on ecosystems and human.