Hazard- and risk based concepts for the assessment of microbiological water quality - part 1

Hazard- and risk based concepts for the assessment of microbiological water quality - part 1 Status quo and current developments with special emphasis on animal faecal sources in alpine and pre-alpine regions Impairment of microbiological water quality is a critical issue since it can cause severe outbreaks or contribute to the background rate of endemic diseases. Human faecal pollution sources are considered of paramount importance and a marked effort has been put into the establishment of sewage disposal and treatment systems. However, animal faecal sources must not be neglected and may constitute a significant hazard due to the almost ubiquitous presence of faecal deposits in the environment and the large number of known zoonotic diseases. Therefore, efficient management of water resources relies thus on the comparative assessment of pathogen hazards and risks associated with faecal contamination from both human and animal sources. This task is challenging when relying on currently available approaches. The aim of this review is, i) to present the status quo of the currently applied methodology of microbiological water quality investigations, ii) to introduce the element of quantitative microbial risk assessment (QMRA) and its possibility to combine with hazard based approaches including microbial source tracking (MST/QMST), and iii) to discuss a list of indicator pathogens for the realisation of QMRA with a special focus on pathogens from animal faecal sources within a regional context. A detailed overview on the available and lacking knowledge in respect to the occurrence and ecology of the selected indicator pathogens from animal sources will be given in the second part of the review. Main emphasis is put on livestock and wild life populations as occurring in alpine or pre-alpine locations in Austria.