We owe a lot of the most convenient aspects of modern life to indoor lighting, yet many scientists worry about how light pollution might affect our health and the overall environment.
This might sound like a needless worry – until you consider that light pollution has already been shown to affect everything from peoples’ moods and circadian rhythms to astronomical observations and the migratory patterns of birds.
Shining a Light on Light Pollution
Light pollution, sometimes called luminous pollution or photopollution, definitely doesn’t have as much headline-grabbing destructive power as, say, a tsunami or government coup. We might not even immediately detect the effects of light pollution until it’s too late.
There’s even a non-profit supporting the idea of less light pollution in our cities, the International Dark-Sky Association. Here are eight reasons why people are concerned:
1. Blocks Out The Night Sky
Pollution by its very nature introduced some contaminant into the environment which, in turn, has a negative effect.
Similar to sound pollution or pollution from carbon dioxide in the environment, light pollution can present contaminants (e.g., glare and skyglow) that have a negative effect on our lives.
In particular, light pollution might block out the stars, especially for urban residents, and make astronomical observations a little tougher for astronomers around big cities.
2. Light Pollution Can Damage Trees
The light from a regular streetlamp can damage certain species of trees by extending trees’ (and plants’) photoperiods. Ideally, trees get on the planet’s wake-sleep schedule dictated by the sun and moon.
What can happen, though, is that trees have what would normally be their winter dormancy period stretched out further and further into winter, causing massive damage.
3. AMA Links To Health Decline
The American Medical Association (AMA) has said that light pollution and glare might be linked to suppressed immune response and even certain kinds of cancer (e.g., breast cancer).
4. Light Pollution Touches Economics
Relatedly, reports also show that a widespread program to cut down on light pollution in major cities could save approximately $10 billion annually.
5. Artificial Light Affects Sleep Patterns
Incandescents and the bluish light from LED (light-emitting diode) lights drive us to be more efficient and work longer hours. That said, artificial lighting might come at a cost.
Light entering through our retinas and going to a brain region known as the hypothalamus might negatively affect our circadian rhythms (i.e., our “sleep-wake” rhythms).
6. …And Be Stressing Us Out
This, according to some experts, could cause us to produce more cortisol (the stress chemical) and less melatonin (the chemical that tells us it’s time for bed).
The end result of all this 24-hour light exposure could be poorer sleep, sudden mood swings and a disruption of our circadian rhythms.
7. Affects Birds’ True North
Astrologers often talk about the answer to some of life’s problems being in the stars, yet for birds that’s almost literally true. Numerous species of birds migrate at night and use the stars, moon and sun to find their way to a more hospitable climate.
Light pollution, or when it’s bad enough “skyglow,” can cause birds to get confused and fly far off course from their intended destination: sometimes birds end up crashing into buildings because of how topsy-turvy their internal compasses get.
8. The Illusion of Safety
Streetlights, according to the Chicago Alley Lighting Project and others, might give us the illusion of safety while actually increasing crime rates. This all goes to show that indoor lighting can be a tremendous ally or hidden danger.