Influence of humic acid addition on the degradation of pharmaceuticals by biofilms in effluent wastewater

Kai Tang, Monica Escola Casas, Gordon Tze Hoong Ooi, Kamilla Marie Speht Kaarsholm, Kai Bester, Henrik Rasmus Andersen

    Research output: Contribution to journalJournal articleResearchpeer-review

    584 Downloads (Pure)


    The degradation of organic micropollutants in wastewater treatment is suspected to depend on co-degradation i.e. be dependent on concentrations of substrate. This complicates predicting and modelling their fate. The effect of humic acid, as a model for complex organic substrate, was investigated in relation to the biodegradation of pharmaceuticals by suspended biofilm carriers adapted to polishing effluent water from a tertiary sewage treatment plant. Twelve out of 22 investigated pharmaceuticals were significantly biodegradable. The biodegradation rate constants of ten of those compounds were increasing with increased humic acid concentrations. At the highest humic acid concentration (30. mgC/L), the biodegradation rate constants were four times higher than the biodegradation rate constants without added humic acid. This shows that the presence of complex substrate stimulates degradation via a co-metabolism-like mechanism and competitive inhibition does not occur. Increases of rate constant per mgC/L are tentatively calculated.
    Original languageEnglish
    JournalInternational Journal of Hygiene and Environmental Health
    Issue number3
    Pages (from-to)604-610
    Publication statusPublished - 2017


    • Public Health, Environmental and Occupational Health
    • Biodegradation
    • Co-metabolism
    • Dissolved organic carbon
    • Humic acid
    • Moving bed biofilm reactor


    Dive into the research topics of 'Influence of humic acid addition on the degradation of pharmaceuticals by biofilms in effluent wastewater'. Together they form a unique fingerprint.

    Cite this