Effects of florfenicol and oxytetracycline on the tropical cladoceran Ceriodaphnia silvestrii: A mixture toxicity approach to predict the potential risks of antimicrobials for zooplankton

Autor(es)

Freitas, Emanuela Cristina ^[1] ; Rocha, Odete ^[2] ; Gaeta Espindola, Evaldo Luiz ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Engn Sch Sao Carlos, Dept Hydraul & Sanitat NEEA CRHEA SHS, Ave Trabalhador Sao Carlense, BR-13560970 Sao Carlos, SP - Brazil

^[2] Univ Fed Sao Carlos, Dept Ecol & Evolutionary Biol, Rodovia Washington Luis Km 235, BR-13565905 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY; v. 162, p. 663-672, OCT 30 2018.
• Citações Web of Science: 1

Resumo

Antimicrobials are commonly used in aquaculture to treat infectious diseases in fish. The overuse of these chemicals, however, has made them a contamination source for the aquatic environments. In this study, single and combined effects of florfenicol (FLO) and oxytetracycline (OTC), two antimicrobials widely used in the fish farming, were evaluated in acute and chronic toxicity tests using the tropical cladoceran Ceriodaphnia silvestrii as a model species. Also, a preliminary risk characterization of FLO and OTC for zooplankton was carried out, taking into account different exposure scenarios. The results obtained revealed that FLO and OTC have adverse effects on the mobility, reproduction and population growth rate of C. silvestrii in single exposures. In addition, mixture effects on the C. silvestrii were more severe than predicted effects based on the Concentration Addition model, showing a synergistic deviation for the mobility and a dose-level dependent deviation for the reproduction (synergism at higher levels than EC60). In relation to the risk characterization, risk quotients (RQs) exceeded 1 for chronic toxicity data obtained in both OTC and mixture exposures, indicating that the concentrations of these chemicals in Brazilian freshwater bodies could potentially present risks for the reproduction of zooplankton species in tropical regions. The RQs obtained for the mixtures were higher than those obtained for each chemical separately. Therefore, it is highly recommended that RQs are derived from single and mixture exposure data in order to obtain a more accurate risk characterization. (AU)

• Processo FAPESP: 16/06671-2 - Avaliação dos efeitos tóxicos isolados e em misturas dos antimicrobianos florfenicol e oxitetraciclina para a biota aquática com ênfase na caracterização de risco ambiental para os ecossistemas tropicais
• Beneficiário: Emanuela Cristina de Freitas
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado