title: Impact of rainfall on the hygienic quality of blue mussels and water in urban areas in the Inner Oslofjord, Norway.
abstract: The effects of precipitation on the hygienic quality of water and blue mussels collected from five different localities in the urban areas in the Inner Oslofjord were investigated, with samples analysed for Escherichia coli, Salmonella spp., pathogenic Vibrio spp., Norovirus, Sapovirus, Cryptosporidium spp. and Giardia duodenalis. The sampling sites were located at varying distances from the outlet of combined sewer overflows (CSO)-impacted rivers/streams. In general, 1-3 log₁₀ increases in fecal indicator bacteria and human pathogens were observed after heavy rainfalls. Blue mussels appeared to be a useful indicator of the impact of sewage at these sites, and generally a good correlation was identified between concentrations of E. coli and other human pathogens in the mussels. Provision of general advice to the public of avoiding areas near the outlets of CSO-impacted rivers after heavy rainfall may reduce the risk of gastroenteritis by bathers and others that may swallow water during recreational activities.
authors.affiliation: Norwegian Institute for Water Research, Gaustadalléen 21, 0349 Oslo, Norway. Electronic address: Ingun.Tryland@niva.no.
authors.forename: Ingun
authors.initials: I
authors.lastname: Tryland
authors.affiliation: Norwegian University of Life Sciences, Campus Adamstuen, 0033 Oslo, Norway.
authors.forename: Mette
authors.initials: M
authors.lastname: Myrmel
authors.affiliation: Norwegian University of Life Sciences, Campus Adamstuen, 0033 Oslo, Norway.
authors.forename: Øyvin
authors.initials: Ø
authors.lastname: Østensvik
authors.affiliation: Norwegian Institute for Water Research, Gaustadalléen 21, 0349 Oslo, Norway.
authors.forename: Aina C
authors.initials: AC
authors.lastname: Wennberg
authors.affiliation: Norwegian University of Life Sciences, Campus Adamstuen, 0033 Oslo, Norway.
authors.forename: Lucy J
authors.initials: LJ
authors.lastname: Robertson
mesh_terms: D000818:Animals; D001419:Bacteria; D002947:Cities; D004784:Environmental Monitoring; D063366:Estuaries; D005243:Feces / Q000382:microbiology; D005843:Geography; D006801:Humans; D049880:Mytilus edulis; D009664:Norway; D011891:Rain; D045483:Rivers / Q000382:microbiology*; D012722:Sewage; D014780:Viruses; D014867:Water; D014871:Water Microbiology
chemical_list: D012722:Sewage; D014867:Water
keywords: Bathing water; Blue mussel; Faecal contamination; Inner Oslofjord; Microbial pathogens; Rainfall