Microplastics and copper impacts on feeding, oxidative stress, antioxidant enzyme activity, and dimethylated sulfur compounds production in Manila clam Ruditapes philippinarum

Mar Pollut Bull. 2024 Nov:208:117022. doi: 10.1016/j.marpolbul.2024.117022. Epub 2024 Sep 26.

Abstract

Microplastics (MPs) are widespread ocean pollutants and many studies have explored their effects. However, research on MPs combined impact with copper (Cu) on dimethylated sulfur compound production is limited. Dimethyl sulfide (DMS) is an important biogenic sulfur compound related to global temperatures. This study examined the ecotoxicological effects of polyamide 6 MPs and Cu on dimethylsulfoniopropionate (DMSP), DMS, and dimethyl sulfoxide (DMSO) production in Manila clams (Ruditapes philippinarum). Our findings showed that MPs and Cu increased oxidative stress, indicated by higher superoxide anion radical production and malondialdehyde levels while decreasing glutathione contents and increasing superoxide dismutase activities. Additionally, MPs and Cu exposure reduced DMS and dissolved DMSO (DMSOd) concentrations due to decreased grazing. These results contribute to a better understanding of the ecotoxicological effects of MPs/Cu on bivalves and their roles in the organic sulfur cycle, suggesting a need for further research on long-term impacts on them.

Keywords: Clam; Copper; DMS; DMSO; DMSP; Microplastics.

MeSH terms

  • Animals
  • Antioxidants* / metabolism
  • Bivalvia* / drug effects
  • Bivalvia* / metabolism
  • Copper* / toxicity
  • Microplastics* / toxicity
  • Oxidative Stress* / drug effects
  • Sulfur Compounds
  • Superoxide Dismutase / metabolism
  • Water Pollutants, Chemical* / toxicity

Substances

  • Water Pollutants, Chemical
  • Copper
  • Antioxidants
  • Microplastics
  • Sulfur Compounds
  • Superoxide Dismutase