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In addition to microbial pathogens that cause gastrointestinal illness, 

 recreational water exposure can also transmit many other microbial pathogens that 

 cause eye, ear, nose, throat, respiratory tract, and skin infections. This too should 

 be an area of further research. Several previous and ongoing epidemiological 

 studies of recreational waters in the U.S. and Great Britain indicate that the 

 incidence of these other microbial diseases may be similar to the incidence of acute 

 gastrointestinal diseases. Some non-gastrointestinal disease causing organisms 

 occur and grow naturally in water, others are transmitted due to the close 

 proximity of bathers in crowded areas, some are from animal sources and yet 

 others occur along with the fecal pathogens from sewage contamination. 



It is important that as we expand our knowledge of both sewage borne and 

 other microbial pathogens, we continue with our existing indicators in developing 

 control strategies, monitoring methods and risk assessments. As the new data and 

 analytical methodologies come about they should be used to improve the 

 framework of our strategies, monitoring methods, and risk determinations to 

 enhance our ability to protect the health of recreational water users. 



National microbiological criteria would provide consistent health protection 

 of recreational water users. However, as we consider national criteria, we need to 

 allow for flexibility in the State-to-State application of the criteria to account for 

 the diversity of geographic and aquatic conditions nationwide. EPA recommends 

 that initial efforts should center around the States' adoption of existing EPA 

 ambient water quality criteria as minimal standards, possibly with minor 



