Toxicological effects of microplastics and phenanthrene to zebrafish (Danio rerio)

Sci Total Environ. 2021 Feb 25:757:143730. doi: 10.1016/j.scitotenv.2020.143730. Epub 2020 Nov 24.

Abstract

The toxicology of microplastics in combination with other pollutants has attracted widespread attention. In this study, zebrafish were exposed to 3 mg/L polystyrene microplastic, 0.2 mg/L phenanthrene, and a combination of both. Zebrafish microplastic uptake, phenanthrene accumulation, antioxidant-associated enzyme activity and related gene expression, immune-associated gene expression, and the gut microflora were measured after 12 and 24 days of exposure. Phenanthrene and microplastic accumulation increased with exposure time and was also greater in the combined exposure group than in the single exposure group. Combined analysis of antioxidant enzyme activity and immune and antioxidant-related genes shows that exposure alone causes oxidative stress in zebrafish, ultimately increasing immunity and the expression of oxidative stress genes, while combined exposure exacerbates these changes. Fusobacteria decreased and Proteobacteria and Bacteroidetes increased in the three exposure groups of gut microorganisms. Overall, our study demonstrates that microplastics enhance the toxicity of phenanthrene and that the two have a synergistic effect.

Keywords: Combined toxicology; Gut microbes; Immune gene; Microplastics; Zebrafish.

MeSH terms

  • Animals
  • Microplastics
  • Oxidative Stress
  • Phenanthrenes* / toxicity
  • Plastics
  • Water Pollutants, Chemical* / toxicity
  • Zebrafish

Substances

  • Microplastics
  • Phenanthrenes
  • Plastics
  • Water Pollutants, Chemical