title: Sunlight inactivation of human viruses and bacteriophages in coastal waters containing natural photosensitizers.
abstract: Sunlight inactivation of poliovirus type 3 (PV3), adenovirus type 2 (HAdV2), and two bacteriophage (MS2 and PRD1) was investigated in an array of coastal waters to better understand solar inactivation mechanisms and the effect of natural water constituents on observed inactivation rates (k(obs)). Reactor scale inactivation experiments were conducted using a solar simulator, and k(obs) for each virus was measured in a sensitizer-free control and five unfiltered surface water samples collected from different sources. k(obs) values varied between viruses in the same water matrix, and for each virus in different matrices, with PV3 having the fastest and MS2 the slowest k(obs) in all waters. When exposed to full-spectrum sunlight, the presence of photosensitizers increased k(obs) of HAdV2, PRD1 and MS2, but not PV3, which provides evidence that the exogenous sunlight inactivation mechanism, involving damage by exogenously produced reactive intermediates, played a greater role for these viruses. While PV3 inactivation was observed to be dominated by endogenous mechanisms, this may be due to a masking of exogenous k(obs) by significantly faster endogenous k(obs). Results illustrate that differences in water composition can shift absolute and relative inactivation rates of viruses, which has important implications for natural wastewater treatment systems, solar disinfection (SODIS), and the use of indicator organisms for monitoring water quality.
authors: Department of Civil and Environmental Engineering, University of California, Berkeley, Berkeley, California, USA.
authors: Andrea I
authors: AI
authors: Silverman
authors: Britt M
authors: BM
authors: Peterson
authors: Alexandria B
authors: AB
authors: Boehm
authors: Kristopher
authors: K
authors: McNeill
authors: Kara L
authors: KL
authors: Nelson
mesh_terms: D000256:Adenoviridae / Q000528:radiation effects*; D025622:Bacteriophage PRD1 / Q000528:radiation effects*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D017909:Levivirus / Q000528:radiation effects*; D010100:Oxygen; D017955:Poliovirus / Q000528:radiation effects*; D054712:Salinity; D013472:Sunlight; D014871:Water Microbiology
chemical_list: D010100:Oxygen