Bacterial inactivation by solar ultraviolet radiation compared with sensitivity to 254 nm radiation.

Our goal was to derive a quantitative factor that would allow us to predict the solar sensitivity of vegetative bacterial cells to natural solar radiation from the wealth of data collected for cells exposed to UVC (254 nm) radiation. We constructed a solar effectiveness spectrum for inactivation of vegetative bacterial cells by combining the available action spectra for vegetative cell killing in the solar range with the natural sunlight spectrum that reaches the ground. We then analyzed previous studies reporting the effects of solar radiation on vegetative bacterial cells and on bacterial spores.

Overview of the inactivation by 254 nm ultraviolet radiation of bacteria with particular relevance to biodefense.

Our goal was to ultimately predict the sensitivity of untested bacteria (including those of biodefense interest) to ultraviolet (UV) radiation. In this study, we present an overview and analysis of the relevant 254 nm data previously reported and available in the literature. The amount of variability in this data prevented us from determining an "average" response for any bacterium.