Light Pollution May Keep Us Awake, Study Finds


The same thing that keeps us safe on the street may be bad for us in the bedroom. Scientists say light pollution from outdoor lighting can leak into our bedrooms, messing with our sleep patterns. These findings from a recently released study will be presented at the annual meeting of the American Academy of Neurology next month.

Human beings have been around for millions of years, but we’ve only had electric light for less than two centuries. Our brains are still wired to equate light with wakefulness and darkness with sleep, but these days when the sun goes down, the lights come on, both indoors and out.

"Our world has become a 24/7 society. We use outdoor lighting, such a street lights, to be more active at night and to increase our safety and security," study author Maurice Ohayon said in a press release. "The concern is that we have reduced our exposure to darkness and it could be affecting our sleep."

Ohayon and his colleagues collected data via phone survey of 15,863 people over the course of eight years. They asked participants about their medical histories, sleep habits, and sleep quality, as well as where they lived. Their addresses were then compared with nighttime data from the Defense Meteorological Satellite Program, which allowed the researchers to measure light pollution near each participant’s home.

They found that people living in large cities were exposed to three to six times more light pollution than people in small towns and rural areas. Sure enough, urban participants reported 2 percent more fatigue and 10 minutes less sleep per night than those living in areas with less light pollution. They were 6 percent more likely to get less than six hours of sleep per night, and 13 percent more likely to be dissatisfied with their sleep. They were also 6 percent more likely to wake up confused in the middle of the night, and were 4 percent more affected by daytime sleepiness and impaired functioning.

But city dwellers shouldn't start packing up just yet. All of these percentage differences are pretty small. There’s also no evidence of causality. It may be that the sleep of city-dwellers is disrupted for other reasons: noise, for example. Still, the researchers believe their hypothesis is sound.

"Light pollution can be found in any sizable city in the world," Ohayon said in the press release. "Yet, excessive exposure to light at night may affect how we function during the day and increase the risks of excessive sleepiness. If this association is confirmed by other studies, people may want to consider room darkening shades, sleep masks or other options to reduce their exposure."

Hubert Grimmig, Kultur- und Tourismus GmbH Gengenbach
Inside the German Town Where Advent Is the Main Attraction
Hubert Grimmig, Kultur- und Tourismus GmbH Gengenbach
Hubert Grimmig, Kultur- und Tourismus GmbH Gengenbach

The German town of Gengenbach takes Christmas very seriously. So seriously that it counts down to the holiday with one of the biggest Advent calendars in the world.

Two decades ago, the town of 11,000 people on the edge of the Black Forest set out to bring in more tourists during the holiday season. So to make its holiday market unique, Gengenbach began turning its town hall into a building-sized Advent calendar.

Now one by one, every night from November 30 to December 23, the windows of Gengenbach’s Baroque city hall light up with artistic creations inspired by a yearly theme. At 6 p.m. each evening, the lights of city hall go up, and a spotlight trains on one window. Then, the window shade pulls up to reveal the new window. By December 23, all the windows are open and on display, and will stay that way until January 6.

Gengenbach's city hall lit up for Christmas
Hubert Grimmig, Kultur- und Tourismus GmbH Gengenbach

Each year, the windows are decorated according to a theme, like children’s books or the work of famous artists like Marc Chagall. For 2017, all the Advent calendar windows are filled with illustrations by Andy Warhol.

According to Guinness World Records, it’s not the absolute biggest Advent calendar in the world. That record belongs to a roughly 233-foot-high, 75-foot-wide calendar built in London’s St Pancras railway station in 2007. Still, Gengenbach’s may be the biggest Advent calendar that comes back year after year. And as a tourist attraction, it has become a huge success in the last 20 years. The town currently gets upwards of 100,000 visitors every year during the holiday season, according to the local tourist bureau.

The Secret World War II History Hidden in London's Fences

In South London, the remains of the UK’s World War II history are visible in an unlikely place—one that you might pass by regularly and never take a second look at. In a significant number of housing estates, the fences around the perimeter are actually upcycled medical stretchers from the war, as the design podcast 99% Invisible reports.

During the Blitz of 1940 and 1941, the UK’s Air Raid Precautions department worked to protect civilians from the bombings. The organization built 60,000 steel stretchers to carry injured people during attacks. The metal structures were designed to be easy to disinfect in case of a gas attack, but that design ended up making them perfect for reuse after the war.

Many London housing developments at the time had to remove their fences so that the metal could be used in the war effort, and once the war was over, they were looking to replace them. The London County Council came up with a solution that would benefit everyone: They repurposed the excess stretchers that the city no longer needed into residential railings.

You can tell a stretcher railing from a regular fence because of the curves in the poles at the top and bottom of the fence. They’re hand-holds, designed to make it easier to carry it.

Unfortunately, decades of being exposed to the elements have left some of these historic artifacts in poor shape, and some housing estates have removed them due to high levels of degradation. The Stretcher Railing Society is currently working to preserve these heritage pieces of London infrastructure.

As of right now, though, there are plenty of stretchers you can still find on the streets. If you're in the London area, this handy Google map shows where you can find the historic fencing.

[h/t 99% Invisible]


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