Ultraviolet Dosimetry in Outdoor Measurements Based on Bacteriophage T7 as a Biosensor

Abstract

A simple method has been worked out for measuring the biologically effective dose (BED) of solar radiation. The method uses phage T7 as a biosensor and it includes field measurements of global and direct UV radiation from the sun in the air; it has been applied to underwater measurements as well. Results of field measurements are presented, with discussion of the angle-dependent sensitivity of the biosensor. A model of spectral irradiance based on the measured values is presented. Relevance of the HT7 unit-derived earlier by us from T7 phage inactivation upon UV radiation-as a measure of the BED is also discussed.

Inactivation of E. coli, B. subtilis spores, and MS2, T4, and T7 phage using UV/H2O2 advanced oxidation

“…T4 and T7 phage have been proposed as biosensors for solar radiation [25], thus it was expected that both T4 and T7 would be sensitive to wavelengths above 295 nm. Similar order of sensitivities was reported by Clancy et al [26] using a 254 nm lamp, where a two log inactivation resulted from a dose of less than 5, 8, and 40 mJ/cm 2 for T4, T7, and MS2 inactivation, respectively.…”

Development and Intercalibration of Ultraviolet Solar Actinometers

“…Actinometers or dosimeters are based on photochemical reactions in solutions (21)(22)(23) and films (24), or the photoreaction of biologically based molecules (e.g. DNA) (25,26) or organisms (27,28). Chemical actinometers measure the photon exposure (16) over a defined wavelength range based on their sunlight response (vide infra), whereas biological dosimeters quantify the effects of sunlight on organisms over a defined action spectrum.…”

The PUR Experiment on the EXPOSE-R facility: biological dosimetry of solar extraterrestrial UV radiation

“…Are the biological dosimeters that have been successfully used on the Earth's surface (Rontó et al 1994;Gróf et al 1996;Fekete et al 1998;Bérces et al 1999;Munakata et al 2000) suitable for UV dosimetry in low Earth orbit (LEO), too, and do they function correctly in the harsh extraterrestrial environment? 2.…”