Novel insights on ecological responses of short- and long-chain perfluorocarboxylic acids in constructed wetlands coupled with modified basalt fiber bio-nest

Xiuwen Qian; Juan Huang; Xinwei Li; Chong Cao; Jiawei Yao

doi:10.1016/j.chemosphere.2024.143384

Novel insights on ecological responses of short- and long-chain perfluorocarboxylic acids in constructed wetlands coupled with modified basalt fiber bio-nest

Chemosphere. 2024 Sep 19:143384. doi: 10.1016/j.chemosphere.2024.143384. Online ahead of print.

Authors

Xiuwen Qian¹, Juan Huang², Xinwei Li¹, Chong Cao³, Jiawei Yao¹

Affiliations

¹ Department of Municipal Engineering, School of Civil Engineering, Southeast University, Nanjing 211189, China.
² Department of Municipal Engineering, School of Civil Engineering, Southeast University, Nanjing 211189, China. Electronic address: 101010942@seu.edu.cn.
³ Department of Municipal Engineering, College of Civil Engineering, Nanjing Forestry University, Nanjing 210037, China.

PMID: 39306106
DOI: 10.1016/j.chemosphere.2024.143384

Abstract

The first investigation based on constructed wetlands coupled with modified basalt fiber bio-nest (MBF-CWs) was performed under exposure of short- and long-chain perfluorocarboxylic acids (PFCAs). In general, both perfluorooctanoic acid (PFOA) and perfluorobutanoic acid (PFBA) caused significant decline of chemical oxygen demand removal by 10.83 % and 4.73 %. However, only PFOA led to marked inhibition on total phosphorus removal by 12.51 % in whole duration. Suppression of removal performance resulted from side impacts on microbes by PFOA. For instance, activities of key enzymes like dehydrogenase (DHA), urease (URE), and phosphatase (PST) decreased by 52.77 %, 40.70 %, and 56.94 % in maximum under PFOA stress, while URE could alleviate over time. By contrast, distinct inhibition was only found on PST in later phases with PFBA exposure. PFCAs had adverse influence on alpha diversity of MBF-CWs, particularly long-chain PFOA. Both PFCAs caused enrichment of Proteobacteria, owing to increase of Gammaproteobacteria and Plasticicumulans by 22.04-35.79 % and 22.91-219.77 %. Nevertheless, some dominant phyla (like Bacteroidota and Acidobacteriota) and genera (like SC-I-84, Thauera, Subgroup_10, and Ellin6067) were only suppressed by PFOA, causing more hazards to microbial decontamination than PFBA did. As for plants, chlorophyll contents tend to decrease with PFOA treatment. Whereas, higher antioxidase activities and more lipid peroxidation products were uncovered in PFOA group, demonstrating more reactive oxygen species brought by long-chain PFCAs. This work offered new findings about ecological effects of MBF-CWs under PFCAs exposure, evaluating stability and sustainability of MBF-CW systems to treat sewage containing complex PFCAs.

Keywords: Constructed wetland; Ecological responses; Modified basalt fiber bio-nest; Perfluorobutanoic acid; Perfluorooctanoic acid.