[INFORMATIVE] The Silent Threat of Light Pollution

The Silent Threat of Light Pollution

By: Smeya Nellipudi

We have all heard about various kinds of pollution: air pollution, noise pollution, water pollution, and many more. But have you ever heard about light pollution? Did you even know that light could be a pollutant? Let’s learn about it in this article!

Introduction
It all started back in 1879 when Thomas Edison invented the light bulb. Since then, our streets have been filled with bulbs, street lights, and many other light-emitting objects. But the excessive use of anything will have its own consequences.

In 1994, when an earthquake knocked out the power in Los Angeles, many anxious residents called local emergency centers to report seeing a strange “giant, silvery cloud” in the dark sky. What they were really seeing—for the first time—was the Milky Way, long obliterated by the urban sky glow. This was all due to the excessive use of lights.

Light pollution is the human-made alteration of outdoor light levels from those occurring naturally. Light pollution can have a number of negative impacts, from disturbing migrating birds and newly hatched sea turtles to marring wilderness experiences and landscape beauty. It can also pose risks to human health.

What causes light pollution?
Light pollution is caused when artificial lights from street lights, mall lights, or any other artificial source of light are misused, resulting in an increase of light upwards into the sky.

Is light pollution a major issue?
Not many people are even aware that the term “light pollution” exists. This silent issue can pose a global threat.

Richard Stevens, a professor and cancer epidemiologist at the University of Connecticut Health Center in Farmington, Connecticut, says light photons must hit the retina for biological effects to occur. “However, in an environment where there is much artificial light at night—such as Manhattan or Las Vegas—there is much more opportunity for exposure of the retina to photons that might disrupt circadian rhythm,” he says. “So I think it is not only ‘night owls’ who get those photons. Almost all of us awake during the night for periods of time, and unless we have blackout shades, there is some electric lighting coming in through our windows. It is not clear how much is too much; that is an important part of the research now.”

(Light pollution in Harrisonburg)

Does light make you feel safe?
Many people use an excess of lighting just to feel safe at night. But would you believe me if I told you that excess light actually does the opposite? Still don’t believe me? Check for yourself.

Have a look at the image below. Do you see the intruder standing in the pathway in the left image? In the right image, all the photographer does is use his hand to cover up the light, exactly what a properly shielded light fixture would do. Do you now see the intruder standing in the pathway? More light doesn’t make us safer! Smarter use of light does!

How do we solve the problem of light pollution?
The simplest way to solve this problem is to just turn OFF the lights! If you can't, you can simply reduce the light usage. Research shows that 75% of artificial sky brightness comes from light escaping directly from fixtures, implying that replacing current fixtures with fully shielded ones would reduce sky brightness to one-fourth of its current levels, not to mention the savings on your electric bill.


Citations
Chepesiuk, Ron. “Missing the Dark: Health Effects of Light Pollution.” Environmental Health Perspectives, U.S. National Library of Medicine, Jan. 2009, www.ncbi.nlm.nih.gov/pmc/articles/PMC2627884/.

Light Pollution: The Overuse & Misuse of Artificial Light at Night - JMU, www.jmu.edu/planetarium/light-pollution.shtml. Accessed 24 Sept. 2024.

“Light Pollution.” Education, education.nationalgeographic.org/resource/light-pollution/. Accessed 24 Sept. 2024.