Autor(es)

Gebara, Renan Castelhano ; Goncalves Alho, Lays de Oliveira ; Rocha, Giseli Swerts ; Mansano, Adrislaine Silva ; Gama Melao, Maria Graca

• Tipo de documento: Artigo Científico
• Fonte: Chemosphere; v. 242, p. 8-pg., 2020-03-01.

Resumo

A large number of metals is present in aquatic ecosystems, often occurring simultaneously, however, the isolated toxicity of them are better well known than their mixtures. Based on that, for the first time we aimed to test the effects of zinc (Zn) and aluminum (Al) mixtures to the microalgae Raphidocelis subcapitata. Regarding isolated toxicity, the 96 h IC50 of Zn and Al based on specific growth rates occurred, respectively, at 0.40 and 27.40 mu M, thus Zn was approximate to 70-fold more toxic than Al. Both Zn and Al altered the cell size and complexity of R. subcapitata at the highest concentrations, although only during Zn exposure was the chlorophyll a fluorescence significantly diminished. Microalgae exposed to Al produced more ROS than during Zn exposure. Moreover, algae produced less ROS at the highest Zn concentration than in the lower concentrations. According to species sensitivity curves (SSD), R. subcapitata was the most sensitive organism to Zn and one of the most sensitive to Al. With respect to mixture toxicity tests, there were significant deviations for both CA (concentration addition) and IA (independent action) models, although data best fitted the CA model and DL (dose level-dependence) deviation, in which metals showed synergic effects at low concentrations and antagonist effects at higher concentrations. (C) 2019 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 18/07988-5 - Bioprospecção, caracterização e otimização de microalgas brasileiras para a biofixação de CO2 e produção de biomoléculas de importância comercial
• Beneficiário: Ana Teresa Lombardi
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 14/14139-3 - Biodiversidade e processos microbianos em ecossistemas aquáticos
• Beneficiário: Hugo Miguel Preto de Morais Sarmento
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 16/00753-7 - Efeitos tóxicos de microcontaminantes emergentes sobre cadeias alimentares planctônicas
• Beneficiário: Maria da Graça Gama Melão
• Modalidade de apoio: Auxílio à Pesquisa - Regular