Effectiveness evaluation of glyphosate oxidation employing the H2O2/UVC process: toxicity assays with Vibrio fischeri and Rhinella arenarum tadpoles.

JUNGES C.M. ; VIDAL E.E. ; ATTADEMO A.M.,; MARIANI M.L. ; CARDELL L. ; NEGRO A.C.; CASSANO A.,; PELTZER P.M.; LAJMANOVICH R.C.; ZALAZAR C.S.

JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART B - PESTICIDES, FOOD CONTAMINANTS, AND AGRICULTURAL WASTES

TAYLOR & FRANCIS INC

Lugar: Londres; Año: 2013 p. 1 - 8

0360-1234

The H2O2/UVC process was applied to the photodegradation of a commercial formulation of glyphosate in water. Two organisms(Vibrio fischeri bacteria and Rhinella arenarum tadpoles) were used to investigate the toxicity of glyphosate in samples M1, M2, andM3 following different photodegradation reaction times (120, 240 and 360 min, respectively) that had differing amounts of residualH2O2. Subsamples ofM1, M2, andM3 were then used to create samplesM1,E, M2,E andM3,E in which the H2O2 had been removed.Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities were measured in tadpoles to determine possible sub-lethaleffects. In V. fischeri, M1,E, which was collected early in the photodegradation process, caused 52% inhibition, whileM3,E, which wascollected at the end of the photodegradation process, caused only 17% inhibition. Survival of tadpoles was 100% in samplesM2, M3,and in M1,E, M2,E and M3,E. The lowest percentages of enzymatic inhibition were observed in samples without removal of H2O2:13.96% (AChE) and 16% (BChE) for M2, and 24.12% (AChE) and 13.83% (BChE) for M3. These results show the efficiency of theH2O2/UVC process in reducing the toxicity of water or wastewater polluted by commercial formulations of glyphosate. Accordingto the ecotoxicity assays, the conditions corresponding toM2 (11 ± 1 mg a.e. L−1 glyphosate and 11 ± 1 mg L−1 H2O2) could be usedas a final point for glyphosate treatment with the H2O2/UV process.