Stress response mechanism of wastewater biological nitrogen removal systems to environmentally realistic concentrations of tire wear particles: Contribution of leachable additives

• Published in: Bioresource technology 2023-11, Vol.387, p.129610-129610, Article 129610
• Main Authors: Ye, Jinyu, Cheng, Ruotong, Chen, Zhoukai, Fang, Chengran, Shi, Meng, Yu, Ran, Qian, Hongchun, Xue, Xiangdong
• Format: Article
• Language: English
• Subjects: Biological nitrogen removal; Electron transfer; Leachable additive; Microbial metabolism; Tire wear particle
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2023.129610

[Display omitted] •First study to investigate the effects of TWPs on nitrogen conversion in BNR systems.•TWPs at environmentally realistic concentrations inhibited both NH4+-N and TN removal.•Leachable additives contribute to the inhibition of TWP on the denitrification process.•TWPs inhibited enzyme activities related to glucose/nitrogen metabolism and electron transport.•ETC activity was consistent with the decrease in TN removal efficiency. The study quantified the biological nitrogen removal performance, microbial metabolism, microbial community structure, and antioxidant system in a sequencing batch reactor under long-term exposure to 0.1 and 1 mg/L tire wear particles (TWPs), and determined the contribution of leachable additives to the biotoxicity of TWPs. The results showed that long-term exposure to 0.1 and 1 mg/L TWPs inhibited both the nitrification and denitrification processes, reducing ammonia nitrogen (NH4+-N) and total nitrogen (TN) removal efficiency. The TWP leachate (TWPL) primarily contributed to the denitrification inhibition by TWPs, potentially due to the high concentration of zinc ions in the leachable additive. Furthermore, both TWP and TWPL inhibit nitrogen conversion, with TWP inhibiting the generation and transfer of electrons, while TWPL only negatively affects the electron transfer process. This study presents novel insights into the impact of TWPs on biological nitrogen removal, underscoring its broader implications for the geochemical nitrogen cycle.