Abstract

SOLIS-GONZALEZ, Gerardo; CORTES-TELLEZ, Alondra A.; TELLEZ-PEREZ, Zaida Irazú  and  BARTOLOME-CAMACHO, María Carmen. Acute toxicity of N-(phosphonomethyl) glycine herbicide on planktonic microorganisms Artemia franciscana and Microcystis aeruginosa. TIP [online]. 2019, vol.22, e192.  Epub Mar 04, 2020. ISSN 1405-888X.  https://doi.org/10.22201/fesz.23958723e.2019.0.192.

Continuous exposure to N-(phosphonomethyl) glycine (glyphosate) produces alterations on aquatic ecosystems, depending on the species or organism, concentration and exposure time. The aim of this research was to evaluate the median lethal concentration (LC50(24)) in Artemia franciscana, as well as the median population inhibitory concentration (IC50) and the coefficient of form (CF) in the cyanobacterium Microcystis aeruginosa in aquatic ecosystems. The results for A. franciscana were an LC50(24) 0.31 mg L-1, and on M. aeruginosa of an IC50(72) 53.95 mg L-1. About the study of the coefficient of form, in the control cells of M. aeruginosa it resulted in a CF≈1, while exposed to 72h-NOEC (No Observable Effect Concentration) was 2.95 mg L-1. The IC50(72) was 53.95 mg L-1 indicating that the cells remain spherical, however, there are significant changes in their volume and the cell surface exposed to IC50(72) of 7.69 ± 1.69 µm3 with 33% volume reduction compared to the control cell, which reflects the ecotoxicological dangers of this herbicide. Exposure to glyphosate resulted as category I (highly toxic) in A. franciscana and category II (toxic) in M. aeruginosa, according to the classification of the United States Environmental Protection Agency (U.S. EPA).

Keywords : glyphosate; acute toxicity; Artemia franciscana; Microcystis aeruginosa; form coefficient.