# Effects of Glyphosate and Its Metabolite AMPA on Aquatic Organisms  
[PERSON]  
1 Research Institute of Fish Culture and Hydrobiology, South Bohemian Research Center of Aquaculture and Biodiversity of Hydroconnes, Faculty of Fisheries and Protection of Waters, The University of South Bohemia in Ceske Budejovice, Zatsi 728/II, 389 25 Vodanny, Czech Republic; [EMAIL_ADDRESS] (A.S.); [EMAIL_ADDRESS] (J.V. )1  
[PERSON]  
1 Research Institute of Fish Culture and Hydrobiology, South Bohemian Research Center of Aquaculture and Biodiversity of Hydroconnes, Faculty of Fisheries and Protection of Waters, The University of South Bohemia in Ceske Budejovice, Zatsi 728/II, 389 25 Vodanny, Czech Republic; [EMAIL_ADDRESS] (A.S.); [EMAIL_ADDRESS] (J.V. )1  
[PERSON]  
1 Research Institute of Fish Culture and Hydrobiology, South Bohemian Research Center of Aquaculture and Biodiversity of Hydroconnes, Faculty of Fisheries and Protection of Waters, The University of South Bohemia in Ceske Budejovice, Zatsi 728/II, 389 25 Vodanny, Czech Republic; [EMAIL_ADDRESS] (A.S.); [EMAIL_ADDRESS] (J.V. )1  
Footnote 1: [[https://www.mdpi.com/journal/applsci](https://www.mdpi.com/journal/applsci)]([https://www.mdpi.com/journal/applsci](https://www.mdpi.com/journal/applsci))  
Footnote 2: [[https://www.mdpi.com/journals/pdf/10/](https://www.mdpi.com/journals/pdf/10/)]([https://www.mdpi.com/journals/pdf/10/](https://www.mdpi.com/journals/pdf/10/))  
\"Roundup\". [7; 8]. Due to initial toxicity tests, which showed relatively low risks to nontarget organisms, including mammals, the exposure limits of glyphosate were set relatively high worldwide. In a short time, use of this popular herbicide increased dramatically due to genetically modified crops (soybean, carola, alfalfa, maize, cotton, and corn) which proved to be glyphosate-tolerant. This high frequency of use in agronomy and urban areas caused the general public to perceive this herbicide as having low toxicity and not being very mobile in the environment [9; 10; 11]. However, ecotoxicology and epidemiology studies published in the last decade indicate the need for further intensive glyphosate toxicity testing. [11]. Furthermore, the World Health Organization's International Agency for Research on Cancer concluded recently that glyphosate is \"probably carcinogenic to humans\" [12; 13; 14]. Generally, the mobility and concentration of glyphosate and aminomethylphosphonic acid (AMPA) are mainly influenced by their bioavailability, bioaccumulation, persistence, ecotoxicity, and transfer into the aquatic environment (Figure 1) [1; 8; 11]. Directly after spraying herbicide in agriculture or in urban areas, glyphosate is absorbed by crops or weeds and penetrates the soil simultaneously. The glyphosate degradation pathway in bacterial strains is the cleavage of the C-N bond and conversion to AMPA, which is either further decomposed or excreted into the environment [15; 16]. AMPA is a primary product of the degradation process of glyphosate and the following nontoxic products are sarcosine and glycine. Unlike AMPA, which is 3-6-fold times more toxic and persistent than glyphosate [17], sarcosine is barely detected in the natural environment [18], except under experimental conditions in a laboratory [16]. On the one hand, the soil has functioned as storage; on the other hand, these contaminants leach below the root zone into groundwater. Glyphosate is also transported by runoff into surface water and consequently accumulated in sediment where glyphosate can be highly mobile [10; 17]. The residual concentrations of glyphosate and AMPA in waters contaminate aquatic organisms via the food web (Figure 1) [11; 15]. Figure 1: Distribution and transport of glyphosate and its major metabolite AMPA into the aquatic environment. Indeed, pesticides have the ability to dissolve themselves to some extent in the environment. However, there is also the potential risk of residues from the biodegradation process [4; 19].