Combined toxicity of polycyclic aromatic hydrocarbons and heavy metals to biochemical and antioxidant responses of free and immobilized Selenastrum capricornutum

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review

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Author(s)

  • Ping Wang
  • Lijuan Luo
  • Lin Ke
  • Tiangang Luan
  • Nora Fung-Yee Tam

Detail(s)

Original languageEnglish
Pages (from-to)673-683
Journal / PublicationEnvironmental Toxicology and Chemistry
Volume32
Issue number3
Publication statusPublished - Mar 2013

Abstract

The aquatic environment often contains different groups of contaminants, but their combined toxicity on microalgae has seldom been reported. The present study compared the toxic effects of combined mixed polycyclic aromatic hydrocarbons (PAHs) and heavy metals on growth and antioxidant responses of free and immobilized microalga, Selenastrum capricornutum. Five PAHs-phenanthrene, fluorene, fluoranthene, pyrene, and benzo[a]pyrene-and four heavy metals at different concentrations-0.05 to 0.1μg Cd2+ ml-1, 0.05 to 1μg Cu2+ ml-1, 0.05 to 1μg Zn2+ ml-1, and 0.5 to 2.5μg Ni2+ ml-1-were examined. Results showed that the chlorophyll a content of free and immobilized S. capricornutum was not affected by PAHs but was significantly inhibited by heavy metals. Conversely, the antioxidant parameters, including the content of reduced glutathione (GSH) and the activities of superoxide dismutase and peroxidase, were significantly induced by both PAHs and metals. For the combined toxic effects of PAHs and heavy metals, cell growth and antioxidant responses varied with exposure time and contaminants and differed between free and immobilized cells. The effects of cocontaminants on the GSH content in free cells were mainly synergistic but changed to antagonistic in immobilized cells. The toxic effects of cocontamination on free cells were also more obvious than those on immobilized cells. These findings suggest that immobilization offers some protection to microalgal cells against toxic contaminants causing differences in the interaction and responses to combined toxicants between free and immobilized cells. Immobilized cells might be more suitable for treating wastewater containing toxic contaminants than free cells. Environ. Toxicol. Chem. 2013;32:673-683. © 2012 SETAC Copyright © 2012 SETAC.

Research Area(s)

  • Antioxidant enzyme, Glutathione, Microalgae, Reactive oxygen species, Toxic effect

Citation Format(s)

Combined toxicity of polycyclic aromatic hydrocarbons and heavy metals to biochemical and antioxidant responses of free and immobilized Selenastrum capricornutum. / Wang, Ping; Luo, Lijuan; Ke, Lin et al.
In: Environmental Toxicology and Chemistry, Vol. 32, No. 3, 03.2013, p. 673-683.

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review