Comments on “Cellular response to infrared radiation involves retrograde mitochondrial signaling”

Effects of Infrared-A Irradiation on Skin: Discrepancies in Published Data Highlight the Need for an Exact Consideration of Physical and Photobiological Laws and Appropriate Experimental Settings

Skin exposure to infrared (IR) radiation should be limited in terms of irradiance, exposure time and frequency in order to avoid acute or chronic damage. Recommendations aimed at protecting humans from the risks of skin exposure to IR (e.g. ICNIRP, ACGIH) are only defined in terms of acute effects (e.g. heat pain and cardiovascular collapse), whereas the actual exposure conditions (e.g. spectral distribution, exposure geometry, frequency and number of exposures, thermal exchange with the environment, metabolic energy production and regulatory responses) are not taken into consideration. Since the IR component of solar radiation reaching the Earth's surface is mainly IR-A, and considering th…