Handler F A
Panasynoptics Corporation, Mclean, Virginia.
Environ Eng Sci. 2019 Jun 1;36(6):667-680. doi: 10.1089/ees.2018.0404. Epub 2019 Jun 4.
This study develops general predictive models for the ultraviolet (UV) radiation dose-response behavior of spores to solar UV irradiation that occurs in the environment and broadband UV irradiation used in water disinfection systems. The approach is demonstrated using previously obtained experimental survival rates for spores deposited on dry surfaces as well as in water and exposed to both narrow band UV radiation as well as broadband UV irradiation from solar exposure and disinfectant lamps. Results are modeled to derive predicted survival rates for spores as a function of irradiance intensity and wavelength, capability for repair, and depletion of available sites for UV damage. The essential features of the approach are expression of the inactivation action spectrum in terms of the probability of an incident photon being absorbed and forming a dimer lesion, and expression of the spore survival as a cumulative binomial distribution for damage. The results provide increased accuracy in estimating dispersed biological hazards, and evaluating the effectiveness of UV air and water disinfectant systems. In addition, the approach for the first time explains the observed reduced inactivation rate in a repair-capable strain compared with a sensitive, repair-deficient strain by accounting for the depletion of available lesion-forming sites due to increasing DNA damage.
本研究针对环境中发生的孢子对太阳紫外线照射以及水消毒系统中使用的宽带紫外线照射的紫外线（UV）辐射剂量-反应行为，开发了通用预测模型。该方法通过使用先前获得的沉积在干燥表面以及水中的孢子的实验存活率进行演示，这些孢子暴露于窄带紫外线辐射以及来自太阳照射和消毒灯的宽带紫外线照射下。对结果进行建模，以得出孢子的预测存活率，该存活率是辐照强度、波长、修复能力以及紫外线损伤可用位点耗竭的函数。该方法的基本特征包括根据入射光子被吸收并形成二聚体损伤的概率来表达失活作用光谱，以及将孢子存活表示为损伤的累积二项分布。这些结果提高了估计分散生物危害以及评估紫外线空气和水消毒系统有效性的准确性。此外，该方法首次通过考虑由于DNA损伤增加导致的可用损伤形成位点的耗竭，解释了与敏感、缺乏修复能力的菌株相比，具有修复能力的菌株中观察到的失活率降低的现象。
