Daily Archives: June 25, 2011

Toilet-to-Tap or Wastewater Reuse?

In 1977 as a college graduate I toured one of the first wastewater reuse facilities in the US….since then reuse has had its forward and backward moments….but it is inevitable….indirect reuse is already widespread…..direct reuse is growing in acceptance….with Singapore emerging as a technology center.  This article (click here) presents an interesting apologetic.

Biofilms as a Reservoir of Waterborne Pathogens

Wingender, J., and Flemming, H.C. Biofilms in drinking water and their role as reservoir for pathogens. Int J Hyg Environ Health. 2011 Jun 20.

Biofilm Centre, University of Duisburg-Essen, Universitätsstraße 5, D-45141 Essen, Germany.

These German researchers review bioflims and their significance in drinking water distribution systems. Such biofilms can become transient or long-term habitats for hygienically relevant microorganisms.

Organisms associated with bioflims include faecal indicator bacteria (e.g., Escherichia coli), obligate bacterial pathogens of faecal origin (e.g., Campylobacter spp.) opportunistic bacteria of environmental origin (e.g., Legionella spp., Pseudomonas aeruginosa), enteric viruses (e.g., adenoviruses, rotaviruses, noroviruses) and parasitic protozoa (e.g., Cryptosporidium parvum). Such organisms can attach to preexisting biofilms, where they become integrated and survive for days to weeks or even longer, depending on the biology and ecology of the organism and the environmental conditions.

Evidence exists that at least a part of the biofilm populations of pathogenic bacteria persists in a viable but non-culturable (VBNC) state.  As such, they go undetected by culture methods. The reviewers conclude that biofilms in drinking water systems can serve as an environmental reservoir for pathogenic microorganisms and represent a potential source of water contamination, resulting in a potential health risk for humans if left unnoticed.

Click here for the abstract of their study.