Evaluation of amicarbazone toxicity removal through degradation processes based on hydroxyl and sulfate radicals.
J Environ Sci Health A Tox Hazard Subst Environ Eng
; 54(11): 1126-1143, 2019.
Article
em En
| MEDLINE
| ID: mdl-31328643
ABSTRACT
The herbicide amicarbazone (AMZ), which appeared as a possible alternative to atrazine, presents moderate environmental persistence and is unlikely to be removed by conventional water treatment techniques. Advanced oxidation processes (AOPs) driven by â¢OH and/or SO4â¢- radicals are then promising alternatives to AMZ-contaminated waters remediation, even though, in some cases, they can originate more toxic degradation products than the parent-compound. Therefore, assessing treated solutions toxicity prior to disposal is of extreme importance. In this study, the toxicity of AMZ solutions, before and after treatment with different â¢OH-driven and SO4â¢--driven AOPs, was evaluated for five different microorganisms Vibrio fischeri, Chlorella vulgaris, Tetrahymena thermophila, Escherichia coli, and Bacillus subtilis. In general, the toxic response of AMZ was greatly affected by the addition of reactants, especially when persulfate (PS) and/or Fe(III)-carboxylate complexes were added. The modifications of this response after treatment were correlated with AMZ intermediates, which were identified by mass spectrometry. Thus, low molecular weight by-products, resulting from fast degradation kinetics, were associated with increased toxicity to bacteria and trophic effects to microalgae. These observations were compared with toxicological predictions given by a Structure-Activity Relationships software, which revealed to be fairly compatible with our empirical findings.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Sulfatos
/
Triazóis
/
Poluentes Químicos da Água
/
Radical Hidroxila
/
Purificação da Água
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
J Environ Sci Health A Tox Hazard Subst Environ Eng
Assunto da revista:
TOXICOLOGIA
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Portugal