Water polluted with glyphosate formulations: effectiveness of a decontamination process using Chlorella vulgaris growing as bioindicator

RENO, U.; REGALDO, L.; VIDAL, E.; MARIANI, M.; C.S. ZALAZAR; GAGNETEN, A.M.

JOURNAL OF APPLIED PHYCOLOGY

SPRINGER

Año: 2016

0921-8971

Abstract The environmental pollution caused by pesticidesis considered a major problem worldwide. Glyphosate is oneof the herbicides most widely used, and its use has increasedsharply in the last years. In this work, the toxicity of fourcommercial glyphosate formulations (Eskoba®, PanzerGold®, Roundup Ultramax® and Sulfosato Touchdown®)was assessed by determining the median effective concentrationat 96 h (96 h-EC50) using the microalga Chlorellavulgaris as the biological model. Although the formulationstested are moderately to slightly toxic to C. vulgaris accordingto the World Health Organization?s toxicity categories foraquatic and terrestrial organisms, this research shows thatthe four formulations are toxic, with Eskoba® the least toxicand Roundup Ultramax® the most toxic one. A UV/H2O2remediation process for the detoxification of the sampleswas tested also. Its effectiveness was evaluated using aC. vulgaris growth inhibition test. Growth inhibition ofC. vulgaris did not reach 18.2 %, indicating the efficacy ofthe UV/H2O2 remediation process to reduce glyphosate toxicity.In some of the samples tested within the first 48 h of theassay, C. vulgaris growth was even increased. The results ofthe present work suggest that the selected species was a good indicator to determine the toxicity level of glyphosate formulationsand shows the relevance of the ecotoxicological tests toevaluate a physicochemical remediation process