Benefits and Risks of Ultraviolet Radiation
Soon after the discovery of microorganisms, biologists began to observe that many varieties of these creatures were able to be incapacitated by exposure to sunlight. Following the discovery of the ultraviolet bandwidth in 1801, scientists attributed the sun’s lethal effect to this invisible energy. Facilitated by the findings of a large body of experimental evidence collected in the decades following these initial hypotheses, contemporary scientists have determined that nearly all bacterial activity can be eradicated or at least attenuated by some wavelength of ultraviolet energy. Due to the overwhelming diversity of microorganisms present in the environment, the resistively and rate of lyses of each species varies greatly. Generally bacteria sterilization when compared to those species whose domain is general exposure was discontinued around the early 1900’s due to the development of sterilization technology utilizing chlorination and ozonation. However, there has been a general trend in industry during the last few decades towards the use of UV for germicidal purification due to its lack of toxic chemical byproducts.
The ultraviolet bandwidth occupies wavelengths roughly between 200 and 400 nanometers. To put into relative terms UV radiation is sandwiched between the higher energy, soft X-rays and lower energy visible light. Purification via exposure to ultraviolet radiation is unique from other types of sterilization modalities due to the fact that it does not necessarily cause death of the target organism. In those pathogens it does not directly kill, the UV radiation effectively alters the creature’s genetic structure. By causing damage to the target bacteria’s Deoxyribonucleic Acid (DNA), the bacteria is sterilized at the genetic level. Thus the organism is no longer able to reproduce and cause disease.