Nanoplastics increase the toxicity of a pharmaceutical, at environmentally relevant concentrations - A mixture design with Daphnia magna

Environ Toxicol Pharmacol. 2023 Oct:103:104258. doi: 10.1016/j.etap.2023.104258. Epub 2023 Sep 4.

Abstract

In aquatic environments, nanoplastics (NPls) can adsorb pharmaceuticals. However, throughout the scientific community, there is scarce knowledge about the interactive effects of the mixture nanoplastics (NPls) with pharmaceuticals to aquatic organisms. Therefore, this study aimed to investigate if the pharmaceutical diphenhydramine (DPH) toxicological effects alters when in presence of polystyrene NPls (PSNPls). To achieve this, Daphnia magna immobilization and different biochemical biomarkers (48-hours exposure) were assessed. Synergistic interactions occurred at environmentally relevant concentrations, PSNPls+DPH induced oxidative damage, whereas no effect was observed at single exposures. With the increase of PSNPls concentration, the DPH concentration causing 50% of effect (EC50) for organisms' immobilization decreased to 0.001 mg/L. In silico analysis suggested that the DPH toxicity to D. magna occurs via the sodium-dependent serotonin transporter. The results showed interactive effects between PSNPls and DPH (implying harmful effects on D. magna), allowing more thoughtful decisions by society and policymakers regarding plastics and pharmaceuticals.

Keywords: Drugs; Mixtures; Polystyrene nanoparticles; Synergistic effects; Water flea.

MeSH terms

  • Animals
  • Daphnia magna
  • Daphnia* / drug effects
  • Daphnia* / metabolism
  • Diphenhydramine* / toxicity
  • Microplastics* / toxicity
  • Oxidative Stress / drug effects
  • Polystyrenes* / toxicity
  • Water Pollutants, Chemical* / toxicity

Substances

  • Water Pollutants, Chemical
  • Microplastics
  • Diphenhydramine
  • Polystyrenes