Recently new Eco lighting has been installed all over North America in the form of LED streetlights made by Dialight. These lights produce a very harsh overly bright white-bluish light. they are at least twice as bright as the High Pressure Sodium lights which are now being phased out. they are very invasive and people say that the light shines into their homes and keeps them up at night. They have also been studied by Professor Abraham Haim, a leading authority on light pollution. White LED whites are actually not white light and really use a blue light spectrum. Haim presented data from an animal study showing the adverse effects of exposure to light at night – particularly short wavelength blue LED light – in which the animals showed varying levels of damage to their metabolic rates, hormone production, body mass and oxygen consumption following exposure, as well as suppressed levels of melatonin production, which is responsible for tumor growth. The light-emitting diode (LED) bulb used in TVs, smartphones, computers
and notebooks, which also gives off a white light, suppresses melatonin
at a rate more than 5 times higher than the High Pressure Sodium bulb. Blue light has also been shown to cause other effects like toxic stress to the retina and other damage to the eyes, look up "blue light hazard" on google. Man's physiology has come to evolve around fire because that is the type of light our ancestors were exposed to. the orange or yellow spectrum is more suited for human eyes because it is more similar to fire, whereas blue light damages our eyes and distorts the production of important brain chemicals having to do with the sleep/wake cycle. the bottom line is that the effects these lights have on human health have not been proven to be safe and adequately studied as this is a very quick change to these LED lights all at once. and this needs to be looked at before they are used in every city in North America and traditional lighting is completely phased out.