By Ajay Mardikar:
If light alone can kill bacteria upto 85%, majority of people should have been leading a healthy life. But the marketing personnel are making different claims without actually providing details of the product. The prospective buyers are left confused and many fall prey to the propaganda. Renowned scientists, Professor in Physics at Post-graduate Department of Physics, RTM Nagpur University, Dr Sanjay Dhoble was also confused after watching an advertisement of a bulb being marketed by a reputed company, recently. “I am searching for the source of claim made by the company about the bulb that kills 85% of bacteria in the atmosphere,” he said. Renowned academician and researcher, Panini Telang explained the impact of light on bacteria. The source of light can be any electric bulb.
“Can an electric bulb kill 85% of the bacteria? Let the source be an old bulb of tungsten filament, mercury vapour or mercury coating bulbs and tube lights, CFL (Compact Fluorescent Light) or LED (Light Emitting Diode), the light emitted is of the same wavelength. The impact of light is same.
It definitely kills bacteria or other micro-organism. This is also applicable to the Sunlight. Sunlight is the most effective source acting against bacteria,” said Telang. Retired Principal of Mohota Science College, Dr Sanjay Charalwar, when contacted, expressed reservations about what was being claimed in the recent advertisement. The experts in the field explained that the photons emit light, which increases or decreases with the velocity of electrons. The impact is less or more with change of colour from red to violet or infra-red to ultra-violet. The impact is different on bacteria in air, liquid or solid bases.
This has not been mentioned by the company, they said. Telang stated that the life earlier was dependent on Sunlight. With the Sunset, most activities used to come to a halt almost completely and resume with sunrise. The life span was short but the people led a healthy life. This is because Sunlight has the greatest impact on bacteria. Renowned scientist Charles Darwin had projected the theory ‘Survival of the Fittest’. With the invention of electricity, lives changed and working even during night has become possible. An American doctor has written a book ‘Survival of the sickest’, as people’s life span has increased but most of them are not healthy. A vast majority of the world’s population is suffering from some or the other disease. By changing the material for preparing bulbs, the heat generating from it has been reduced. However, the impact on bacteria is same, the experts stated.