title: Assessing pathogen risk to swimmers at non-sewage impacted recreational beaches.
abstract: The risk of gastrointestinal illness to swimmers from fresh sewage and non-sewage fecal sources at recreational beaches was predicted using quantitative microbial risk assessment (QMRA). The QMRA estimated the probability of illness for accidental ingestion of recreational water with a specific concentration of fecal indicator bacteria, here the geometric mean enterococci limit of 35 cfu 100 mL(-1), from either a mixture of sources or an individual source. Using seagulls as an example non-sewage fecal source, the predicted median probability of illness was less than the illness benchmark of 0.01. When the fecal source was changed to poorly treated sewage, a relativity small difference between the median probability of illness and the illness benchmark was predicted. For waters impacted by a mixture of seagull and sewage waste, the dominant source of fecal indicator was not always the predicted dominant source of risk.
authors.affiliation: U.S. Environmental Protection Agency, National Exposure Research Laboratory, Cincinnati, Ohio 45268, USA. Schoen.mary@epa.gov
authors.forename: Mary E
authors.initials: ME
authors.lastname: Schoen
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Ashbolt
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D001493:Bathing Beaches / Q000592:standards; D046091:Charadriiformes; D002648:Child; D002675:Child, Preschool; D016983:Enterococcus / Q000302:isolation & purification; D004784:Environmental Monitoring; D005243:Feces / Q000382:microbiology; D005767:Gastrointestinal Diseases / Q000382:microbiology; D006801:Humans; D012307:Risk Factors; D012722:Sewage / Q000382:microbiology; D018709:Statistics, Nonparametric; D013550:Swimming; D014871:Water Microbiology / Q000592:standards; D014876:Water Pollution / Q000032:analysis
chemical_list: D012722:Sewage