Many people have experienced a night of sleeplessness, or waking up in the middle of the night, unable to return to sleep.
Though sleeplessness is often seen as a sign of stress or too much caffeine, the effects of artificial light also play a role.
“In order for humans to function, light photons must hit the retina. However, when there is too much artificial light at night, there may be an overexposure of photons to the retina, disrupting circadian rhythm,” said Dr. Li Li, a professor of cognitive psychology at the University of Hong Kong.
The sleeping aspect of the circadian cycle is largely controlled by melatonin, a hormone produced in the pineal gland of the brain.
Naturally, the body’s internal clock controls the time you wake up and the time you sleep by raising or lowering levels of melatonin.
“Melatonin levels usually rise in the mid to late evening, remain high for most of the night, and then drop in the early morning hours,” Dr. Li said.
However, this normal process is affected by light. The more light there is, the less melatonin your body produces.
Eventually, if there is too much exposure to light at night, the body may not be able to produce enough melatonin to sleep.
And, in fact, this deficiency is not only affected on a day-to-day basis. The body may permanently be unable to produce enough melatonin, leading to insomnia.
The consequences of melatonin depletion are potentially far-reaching.
According to Professor Samuel Ho of the University of Hong Kong, melatonin is also a hormone that slows the risk of cancer.
“Melatonin impacts the endocrine system and prevents cancerous growth formation and development,” Ho said.
In women, decreased melatonin could put them at an increased risk of breast cancer and large intestine or rectal cancers.
Beyond increased risk for cancer, an irregular circadian rhythm may also lead to weight gain, impulsive behavior and
slower cognitive functions.
Both specialists recommend using thick curtains and blackout shades, with no artificial light present in the bedroom at night.
“One of the tricks I recommend is to shut off your bright light 30 minutes before sleep, so you can signal to your body that it is nighttime. Don’t bring any electronics or anything with a light emitting from it, and don’t stare at the computer or anything with a screen,” Dr. Li said.
Although light is such an important part of our lives, artificial glow late at night does result in dangerous and frustrating consequences.
Artificial lights are an integral part of modern life. Along with allowing humans more hours of productivity, it also gives us more time for recreation and activities. It creates safer and more welcoming environments, so that we’re not limited to staying indoors after the sun goes down.
However, with our illuminating innovations, abuse and overuse also follow.
Today, Hong Kong is bustling with people, both natives and tourists from around the world.
People come to Hong Kong to experience the city life, and along with them are plenty of businesses vying for customers and the government drawing in more tourists. After all, this is the city that proudly hosts The Symphony of Lights.
These two factors, on top of the seven million residents in the city, leads to an area surrounded by artificial light and light pollution.
Light pollution, according to the International Dark-sky Association, is “any adverse effect of artificial light, including
sky glow, glare, light trespass, light clutter, decreased visibility at night, and energy waste.”
Today, high rise towers and street lamps are all illuminated with bright lights. From morning until night, they shine even when no one is using them.
Billboards and store signs are among the worst offenders, with unnecessarily bright bulbs, sometimes even accompanied by flashing effects and neon colors.
It is at that point, when artificial lights are a waste of energy, bothersome and unnecessary, that it becomes light pollution.
From human and animal health, astrological, environmental and economic viewpoints, light pollution, when taken too far, can have damaging consequences.
Lights are necessary in many aspects of our lives, from safety to productivity, but the use of artificial illumination should be treated with care, rather than thought of as inconsequential.
Mr. So explains light pollution on a Physics perspective
I walked along Nathan Road from Tsim Sha Tsui, past Jordan and to Yau Ma Tei at 3am, to observe the sleeplessness of the sleepless city.
In Hong Kong, if your neighbour is making too much noise, it is okay to complain—as long as it is after 11pm. It is a common procedure in Hong Kong. You just call the police, and they will go speak to whoever is creating the noise. Happens a lot in Soho where bars are located directly under residential flats.
So what if the billboard outside is too bright late at night and you can’t sleep?
The pollution complaint reporting form on the government website does not have a ticking box for light pollution; although you can tick the “Others, please specify” section.
Instead you can call the Environmental Protection Department (EPD) at 2838-3111 and complain.
But if the complaints were actually heard, there should be less lights in Hong Kong. It’s probably as effective as calling about the noise pollution.
Besides, Hong Kong lacks the legal regulation to prevent light pollution, whereas other large cities do.
Created by LightedHK.com
Source: WWF Fund