Tire materials disturb transformations of nitrogen compounds and affect the structure of biomass in aerobic granular sludge reactors

• Published in: Journal of hazardous materials 2024-03, Vol.465, p.133223, Article 133223
• Main Authors: Jachimowicz, Piotr, Peng, Ruoting, Hüffer, Thorsten, Hofmann, Thilo, Cydzik-Kwiatkowska, Agnieszka
• Format: Article
• Language: English
• Subjects: Additives; Microbial community; Microplastics; Organic compounds; Wastewater treatment
• ISSN: 0304-3894; 1873-3336; 1873-3336
• DOI: 10.1016/j.jhazmat.2023.133223

Tire materials (TMs) present a notable hazard due to their potential to release harmful chemicals and microplastics into the environment. They can infiltrate wastewater treatment plants, where their effects remain inadequately understood, raising concerns regarding their influence on treatment procedures. Thus, this study investigated the impact of TMs in wastewater (10, 25, 50 mg/L) on wastewater treatment efficiency, biomass morphology, and microbial composition in aerobic granular sludge (AGS) reactors. TM dosage negatively correlated with nitrification and denitrification efficiencies, reducing overall nitrogen removal, but did not affect the efficiency of chemical-oxygen-demand removal. The presence of TMs increased the diameter of the granules due to TM incorporation into the biomass. The most frequently leached additives from TMs were N-(1,3-dimethylbutyl)-N′-phenyl-1,4-phenylenediamine, benzothiazole (BTH), and 2-hydroxybenzothiazole. In the treated wastewater, only BTH and aniline were detected in higher concentrations, which indicates that tire additives were biodegraded by AGS. The microbial community within the AGS adapted to TMs and their chemicals, highlighting the potential for efficient degradation of tire additives by bacteria belonging to the genera Rubrivivax, Ferruginibacter, and Xanthomonas. Additionally, our research underscores AGS's ability to incorporate TMs into biomass and effectively biodegrade tire additives, offering a promising solution for addressing environmental concerns related to TMs. [Display omitted] •Tire materials (TMs) reduced nitrification, impacting nitrogen removal by aerobic granules.•The most common tire additives in treated wastewater were aniline and benzothiazoles.•The rate of TMs incorporation in biomass was correlated with TM load in wastewater.•TMs shifted EPS-producing bacteria communities to micropollutant-resistant one.•TMs boosted bacterial metabolism for biodegradation and DNA repair.