Abamectin in soils: Analytical methods, kinetics, sorption and dissipation

Autor(es)

Dionisio, Andreza Camilotti ^[1] ; Rath, Susanne ^[1]

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas, Inst Chem, Dept Analyt Chem, POB 6154, BR-13084970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Chemosphere; v. 151, p. 17-29, MAY 2016.
• Citações Web of Science: 12

Resumo

Abamectin is a broad-spectrum antiparasitic agent that has been widely employed in veterinary medicine and has also been used as a pesticide in agriculture. Veterinary drugs may reach the soil and may be transported to surface and ground waters, posing risks to terrestrial and aquatic organisms. Sorption, transformation and transport processes are primarily responsible for the fate of these substances in the environment. In this study, the sorption and the aerobic dissipation of abamectin in Brazilian soils (sand, clay and sandy-clay) were evaluated. For sorption studies, batch equilibrium experiments were performed. Sorption and desorption isotherms were fitted to the Freundlich model. Abamectin showed a high affinity to soil particles, with Freundlich sorption and desorption coefficients ranging from 44 to 138 mu g(1-1/n) (cm(3))(1/n) g(-1) and from 89 to 236 mu g(1-1/n) (cm(3))(1/n) g(-1) respectively. Dissipation of abamectin was evaluated in sterile and non-sterile soils in an aerobic and dark environment under controlled temperature and humidity. The time required for a 50% reduction of the amount of abamectin present in non-sterile soils was up to 4 days, and the time period for 90% dissipation was up to 12 days. In sterilized soils, there was no reduction in the concentration of abamectin over 37 days of exposure, suggesting that aerobic microbial degradation must have been the primary mechanism responsible for the dissipation of abamectin in soils. (C) 2016 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 13/09543-7 - Resíduos de medicamentos veterinários no ambiente
• Beneficiário: Susanne Rath
• Modalidade de apoio: Auxílio à Pesquisa - Temático