International. Recently, the journal of Environmental Mana-gement published a investigación conducted by scientists from Italy, the United States and Israel, which analyzed the production of melatonin in the presence of three types of lighting: sodium bulbs, halide lamps and LEDs.
Melatonin is a hormone that is generated in the pineal gland of the brain and that places the body in night mode, also regulates the so-called biological clock responsible for biorhythms. Low production of these hormones causes behavioral disturbances and health problems.
The research concluded that all lights decrease melatonin production when they are cold white (bluish). However, while stadium light reduces it three times more than sodium light, LEDs trim this hormone five times more.
The focus of discussion is on the fact that LEDs, which save more energy than conventional lights, will be used for public lighting, and with these effects, they would enter a higher level of regulation for their installation.
However, contrasting with the research, some specialists in this kind of lighting, such as the electronic engineer of the UPB, Jenaro Briñón Vélez assure that "what the study does not analyze is the percentage of night time necessary to reduce these levels. Assuming that the exposure is harmful to health, it is necessary to note that the frequency that affects the production of melatonin is that related to blue radiation close to 470nm (wavelengths), which in cold white luminaires (greater than 5,000ºK) is very high. "
It should be noted that the majority of the population is not exposed for a long time to radiation from artificial luminaires. With LED lighting it is feasible to choose warmer white colors, renouncing maximum efficiency, but protecting living beings from radiation in the blue zone.
"It doesn't matter if the cold light is from a fluorescent tube or a halogen mercury lamp or an LED, what stops the production of melatonin is the color of the light, it is not an LED," said Edgardo Boqué, president of RGB Lighting Systems SA.
Engineer Briñón concluded that "it would be important to regulate within the regulations of public lighting with LEDs, the appropriate minimum color temperatures, the minimum color reproduction indices (IRC) and the maximum permissible glare levels (UGR)".
According to this, appropriate regulation is the solution to reduce any biological risk. It is important to define the less aggressive color temperatures and the factors exposed above in order to regulate the new LED lighting.
