Do NH4+-N and AOB affect atenolol removal during simulated riverbank filtration?

Jian Zhao; Shangbiao Fang; Weixiao Qi; Huijuan Liu; Jiuhui Qu

doi:10.1016/j.chemosphere.2022.134653

Do NH₄⁺-N and AOB affect atenolol removal during simulated riverbank filtration?

Chemosphere. 2022 Aug:301:134653. doi: 10.1016/j.chemosphere.2022.134653. Epub 2022 Apr 18.

Authors

Jian Zhao¹, Shangbiao Fang¹, Weixiao Qi², Huijuan Liu³, Jiuhui Qu¹

Affiliations

¹ Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China.
² Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China; Beijing Laboratory of Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing, 100084, China. Electronic address: wxqi@mail.tsinghua.edu.cn.
³ Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China; Beijing Laboratory of Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing, 100084, China.

PMID: 35447203
DOI: 10.1016/j.chemosphere.2022.134653

Abstract

Biodegradation is regarding as the most important organic micro-pollutants (OMPs) removal mechanism during riverbank filtration (RBF), but the OMPs co-metabolism mechanism and the role of NH₄⁺-N during this process are not well understood. Here, we selected atenolol as a typical OMP to explore the effect of NH₄⁺-N concentration on atenolol removal and the role of ammonia oxidizing bacteria (AOB) in atenolol biodegradation. The results showed that RBF is an effective barrier for atenolol mainly by biodegradation and adsorption. The ratio of biodegradation and adsorption to atenolol removal was dependent on atenolol concentration. Specifically, atenolol with low concentration (500 ng/L) is almost completely removed by adsorption, while atenolol with higher concentration (100 μg/L) is removed by biodegradation (51.7%) and adsorption (30.8%). Long-term difference in influent NH₄⁺-N concentrations did not show significant impact on atenolol (500 ng/L) removal, which was mainly dominated by adsorption. Besides, AOB enhanced the removal of atenolol (100 μg/L) as biodegradation played a more crucial role in removing atenolol under this concentration. Both AOB and heterotrophic bacteria can degrade atenolol during RBF, but the degree of AOB's contribution may be related to the concentration of atenolol exposure. The main reactions occurred during atenolol biodegradation possibly includes primary amide hydrolysis, hydroxylation and secondary amine depropylation. About 90% of the bio-transformed atenolol was produced as atenolol acid. AOB could transform atenolol to atenolol acid by inducing primary amide hydrolysis but failed to degrade atenolol acid further under the conditions of this paper. This study provides novel insights regarding the roles played by AOB in OMPs biotransformation during RBF.

Keywords: Ammonia-oxidizing bacteria (AOB); Atenolol; Biodegradation pathway; Biodegradation products; Riverbank filtration (RBF).

MeSH terms

Amides
Ammonia / metabolism
Atenolol*
Betaproteobacteria* / metabolism
Biodegradation, Environmental
Filtration
Oxidation-Reduction

Substances

Amides
Atenolol
Ammonia