Effects of environmental concentrations of 6PPD and its quinone metabolite on the growth and reproduction of freshwater cladoceran

• Published in: The Science of the total environment 2024-10, Vol.948, p.175018, Article 175018
• Main Authors: Shi, Chaoli, Wu, Fusen, Zhao, Zirui, Ye, Tianhao, Luo, Xinru, Wu, Yang, Liu, Zhiquan, Zhang, Hangjun
• Format: Article
• Language: English
• Subjects: 6PPD; 6PPD quinone; byproducts; Daphnia pulex; environment; Environmental contaminant; fecundity; freshwater; Growth; metabolites; mortality; quinones; Reproductive capacity; reproductive performance; risk
• ISSN: 0048-9697; 1879-1026; 1879-1026
• DOI: 10.1016/j.scitotenv.2024.175018

The widespread occurrence and accumulation of N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine (6PPD) and its quinone metabolite, 6PPD quinone (6PPD-Q), have been globally recognized as a critical environmental issue. However, knowledge on the adverse effects of 6PPD and 6PPD-Q on freshwater invertebrates is limited. This study investigated the effects of 6PPD and its oxidative byproduct, 6PPD-Q, on the growth and reproduction of Daphnia pulex. Through 21-day exposure experiments, we measured the uptake of 0.1, 1, and 10 μg/L 6PPD and 6PPD-Q by D. pulex and assessed the effects on growth and fecundity of D. pulex. While 6PPD and 6PPD-Q did not affect the mortality rate of D. pulex, 6PPD-Q exposure inhibited the growth of D. pulex, indicating potential ecological risks. In particular, the reproductive capacity of D. pulex remained unaffected across the tested concentrations of 6PPD and 6PPD-Q, suggesting specific toxicological pathways that warrant further investigation. This study underscored the importance of evaluating the sublethal effects of emerging contaminants such as 6PPD and 6PPD-Q on aquatic invertebrates, and highlighted the need for comprehensive risk assessments to better understand their environmental impacts. [Display omitted]