Toxicological effects of tire rubber-derived 6PPD-quinone, a species-specific toxicant, and dithiobisbenzanilide (DTBBA) in the marine rotifer Brachionus koreanus

Mar Pollut Bull. 2023 Jul:192:115002. doi: 10.1016/j.marpolbul.2023.115002. Epub 2023 May 12.

Abstract

The ingredients of tire-rubber products include a complex range of chemicals additives, most of which are leached into surrounding water as unmeasured toxicants with unexplored ecotoxicological impacts. The present study summarizes the reported species-specific acute toxicity of N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine-quinone (6PPD-Q), the ozonation product of anti-oxidant 6PPD used in tire rubber. Also, chronic toxicity and oxidative response of 6PPD-Q and another tire-rubber derivative, 2',2'''-dithiobisbenzanilide (DTBBA), in rotifer Brachionus koreanus were investigated. Although 6PPD-Q has been reported to be highly toxic to several species of salmonids, only moderate chronic toxicity was observed in B. koreanus. In contrast, DTBBA significantly retarded the population growth and fecundity. The varying toxicity of 6PPD-Q and DTBBA was linked to the level of reactive oxygen species in which DTBBA exposure caused a significant concentration-dependent increase. Our results imply unanticipated risks to aquatic species posed by chemical additives in tire-rubber which may be considered emerging contaminants of toxicological concern.

Keywords: 6PPD-Q; DTBBA; Rotifer; Tire additives; Tire rubber; Tire wear particles.

MeSH terms

  • Animals
  • Antioxidants / toxicity
  • Benzoquinones* / toxicity
  • Hazardous Substances / toxicity
  • Phenylenediamines* / toxicity
  • Reactive Oxygen Species / metabolism
  • Rotifera* / drug effects
  • Rubber* / toxicity
  • Water Pollutants* / toxicity

Substances

  • Antioxidants
  • Hazardous Substances
  • Reactive Oxygen Species
  • Rubber
  • N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine quinone
  • Phenylenediamines
  • Benzoquinones
  • Water Pollutants