Some Thoughts on the E.coli Outbreak in Germany

I suppose the many hundreds of students who have attended my introductory lectures on wastewater treatment can attest to my call for the past thirty years for microbial standards to be placed on wastewater treatment plants, and in particular to focus more closely on pathogen removal during treatment.  Wastewater treatment plants, especially activated sludge reactors, are ideal places for new strains of bacteria and antibiotic resistance to develop.  Our simple barrier approach to pathogen control based largely on dilution of effluents and the disinfection of drinking water has served us well, but the reuse of wastewater effluents, contaminated surface and ground waters are all direct routes to the food chain.  While the source of the current outbreak of E. coli  in Germany remains unknown, we should not rule out the very high possibility of such a link.  The need for better operational management coupled with final effluent disinfection to deal with pathogen release from treatment plants must be put on the agenda for a revised Urban Wastewater Directive, where emphasis is placed equally on both environmental and public health protection.