Pseudomonas aeruginosa-fecal coliform relationships in estuarine and fresh recreational waters.

Abstract

Most states have established water quality standards for r creational waters based on the coliform index,1 even though there is no conclusive evidence of a correlation between coliform levels in recreational waters and the incidence of illness in populations bathing therein.2'3 The absence of conclusive evidence could be real in that there may be little if any hazard of enteric infection to bathers even when the recreational waters used are grossly polluted with fecal wastes. Moore et al^ concluded that, in the absence of gross contamination with visible fecal ma terial, there is a negligible health hazard associated with bathing in wastewater polluted marine waters. Stevenson5 did observe two instances that suggested a cor relation between gastrointestinal disease and coliform densities in freshwaters used for bathing. He noted that the evidence was far from conclusive, however. It is the present authors' view that there are measurable health hazards associated with swimming in waters polluted with fecal wastes but that limitations in the design of previous studies have precluded detection of these hazards. For example, in none of the previous studies, including those of Stevenson,5 was swimming or bath ing defined so that the incidence of illness was measured in the population actually, at risk, that is, individuals with significant exposure of their upper body orifices to the water. Furthermore, many workers have questioned the validity of total coliform densities as an index of fecal pollution.2'3> 6 Several states use fecal coliform standards; in fact, the proposed National Technical Advisory Council (ntac) standard is based on fecal coliform densities in water.7 There are, however, no data correlating fecal coliform densities to enteric disease