Neutrophilic Iron Oxidizing Bacteria: Occurrence and Relevance in Biological Drinking Water Treatment

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Rapid sand filtration (RSF) is an economical way to treat anoxic groundwater around the world. It consists of groundwater aeration followed by passage through a sand filter. The oxidation and removal of ferrous iron, which is commonly found in anoxic groundwaters, is often believed to be a fully physicochemical process. However, persistently low temperatures in RSF across Denmark may negatively affect the kinetics of chemical oxidation. The slower chemical oxidation of ferrous iron may increase the chances for iron bioconversion by neutrophilic iron-oxidizing bacteria (FeOB), which are found naturally in many environments.
In this study, we used a combination of a cultivation-based opposing gradient enrichment technique and 16S rRNA gene targeted molecular tools to isolate, quantify and identify FeOB from a RSF. The microscopic quantification of selectively enriched FeOB cell revealed that in RSF, neutrophilic iron oxidizers were present at the level of up to 7 105 cells per gram sediment. The spatial abundance and diversity of FeOB inferred by DGGE fingerprinting differed greatly both between and within individual sand filters. The results suggest a larger than assumed role of FeOB in iron removal at waterworks using RSF technologies.
Original languageEnglish
Publication date2012
Number of pages8
Publication statusPublished - 2012
Event2012 IWA World Water Congress and Exhibition - Busan, Korea, Republic of
Duration: 16 Sep 201221 Sep 2012


Conference2012 IWA World Water Congress and Exhibition
CountryKorea, Republic of
Internet address


  • Ion ovidizing bacteria
  • IOB
  • FeOB
  • Diversity
  • Neutrophilic
  • Rapid sand filtration

Cite this

Gülay, A., Musovic, S., Albrechtsen, H-J., & Smets, B. F. (2012). Neutrophilic Iron Oxidizing Bacteria: Occurrence and Relevance in Biological Drinking Water Treatment. Paper presented at 2012 IWA World Water Congress and Exhibition, Busan, Korea, Republic of.