1,4-Dioxane removal in nitrifying sand filters treating domestic wastewater: Influence of water matrix and microbial inhibitors

Cheng Shiuan Lee, Mian Wang, Patricia M. Clyde, Xinwei Mao, Bruce J. Brownawell, Arjun K. Venkatesan

Research output: Contribution to journalArticlepeer-review

4 Scopus citations


1,4-Dioxane is a recalcitrant pollutant in water and is ineffectively removed during conventional water and wastewater treatment processes. In this study, we demonstrate the application of nitrifying sand filters to remove 1,4-dioxane from domestic wastewater without the need for bioaugmentation or biostimulation. The sand columns were able to remove 61 ± 10% of 1,4-dioxane on average (initial concentration: 50 μg/L) from wastewater, outperforming conventional wastewater treatment approaches. Microbial analysis revealed the presence of 1,4-dioxane degrading functional genes (dxmB, phe, mmox, and prmA) to support biodegradation being the dominant degradation pathway. Adding antibiotics (sulfamethoxazole and ciprofloxacin), that temporarily inhibited the nitrification process during the dosing period, showed a minor effect in 1,4-dioxane removal (6–8% decline, p < 0.05), suggesting solid resilience of the 1,4-dioxane-degrading microbial community in the columns. Columns amended with sodium azide significantly (p < 0.05) depressed 1,4-dioxane removal in the early stage of dosing but followed by a gradual increase of the removal over time to >80%, presumably due to a shift in the microbial community toward azide-resistant 1,4-dioxane degrading microbes (e.g., fungi). This study demonstrated for the first time the resilience of the 1,4-dioxane-degrading microorganisms during antibiotic shocks, and the selective enrichment of efficient 1,4-dioxane-degrading microbes after azide poisoning. Our observation could provide insights into designing better 1,4-dioxane remediation strategies in the future.

Original languageEnglish (US)
Article number138304
StatePublished - May 2023
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Environmental Engineering
  • Environmental Chemistry
  • General Chemistry
  • Pollution
  • Public Health, Environmental and Occupational Health
  • Health, Toxicology and Mutagenesis


  • 1,4-Dioxane
  • Biodegradation
  • Nitrogen removing biofilter
  • Onsite wastewater system
  • Sand filter


Dive into the research topics of '1,4-Dioxane removal in nitrifying sand filters treating domestic wastewater: Influence of water matrix and microbial inhibitors'. Together they form a unique fingerprint.

Cite this