title: Sunlight inactivation of Campylobacter jejuni and Salmonella enterica, compared with Escherichia coli, in seawater and river water.
abstract: The inactivation of Campylobacter jejuni and Salmonella enterica, compared with Escherichia coli, was determined in 100 l chambers of seawater and river water located at an outdoor site. The chambers (paired with dark controls) were seeded with waste stabilization pond effluent and laboratory-cultured pathogens, and exposed to sunlight in summer and winter experiments. All sunlight inactivation (k(S)) rates, as a function of cumulative global solar radiation (insolation), were far higher than the corresponding dark (k(D)) rates, with a ranking (and average k(S) rates for seawater and river water, respectively) of: C. jejuni (3.23; 2.34)>S. enterica (0.51; 0.37)>E. coli (0.34; 0.26). All the T(90) (time to 90% inactivation) values were higher in winter than in summer, but there was far greater similarity between the summer and winter S(90) (insolation needed for 90% inactivation) values. The rapid inactivation of C. jejuni was attributed to a high susceptibility to photooxidative damage. The results suggest that, in sunlight-exposed waters, E. coli will be a more conservative indicator for C. jejuni than for S. enterica, and C. jejuni transmission as a pathogenic agent is less likely than for S. enterica.
authors: Institute of Environmental Science and Research, Christchurch, New Zealand. lester.sinton@esr.cri.nz
authors: Lester
authors: L
authors: Sinton
authors: Carollyn
authors: C
authors: Hall
authors: Robin
authors: R
authors: Braithwaite
mesh_terms: D016123:Campylobacter jejuni / Q000254:growth & development / Q000528:radiation effects*; D004203:Disinfection / Q000379:methods; D004926:Escherichia coli / Q000254:growth & development / Q000528:radiation effects*; D045483:Rivers / Q000382:microbiology; D019779:Salmonella enterica / Q000254:growth & development / Q000528:radiation effects*; D012623:Seawater / Q000382:microbiology; D013472:Sunlight; D014871:Water Microbiology; D014873:Water Pollutants / Q000528:radiation effects*
chemical_list: D014873:Water Pollutants