Light pollution, US focus, flat. [Credit: Falchi et al., Science Advances, including Dan Duriscoe/NPS; Bob Meadows/NPS; Jakob Grothe/NPS contractor, and Matthew Price/CIRES and CU-Boulder] Light pollution now blots out the Milky Way for eight in ten Americans. Bright areas in this map show where the sky glow from artificial lighting obscures the stars and constellations. An international team of researchers has released a new world atlas of artificial sky brightness, in a paper published in Science Advances June 10. An interactive version of this map and data download instructions are at: cires.colorado.edu/artificial-sky
Pollution is not exclusive to Earth’s ecology
When we think of Earth Day concerns and ecology, our minds fix on toxins in the many landscapes that compose our environment: water pollution, air pollution, soil pollution.
But there are other kinds of pollution which we can also include when we think about the environment surrounding our sleeping spaces.
We encounter an internal “climate” every night we go to bed, with external (and internal) influences that can completely disrupt our own body ecology.
We already know (or should know!) that using electronic devices at night (without filters) puts us all at risk for insomnia and may even have negative epigenetic consequences for our offspring, as the eyes’ exposure to blue spectrum light is well known to halt the release of the “sleep hormone,” melatonin, into the bloodstream.
We need melatonin in order to fall asleep, and all kinds of light can disrupt its regulation of our sleep-wake cycles. This circadian disruption can lead to chronic illness, even cancer, if left unaddressed.
But staring down the smartphone at bedtime isn’t the only sleep-disrupting light pollution problem we can encounter. There are other kinds of light pollution we should also be wary of as we turn in for the night.
Internal light pollution
Those low-cost LED lights you’re swapping with regular incandescent bulbs in your lamps and light fixtures may be too bright for you and your family. The long-term savings and carbon footprint may be appealing, but only if they don’t turn your family into sleepless zombies. One solution is to buy LED bulbs that are labeled as “blueblocking” or “filtered for blue light” or considered “soft” and not “bright.”
Even the tiny power lights emitted from appliances can be disruptive to sleep. In the bedroom, one easy solution is to place a piece of duct tape over the lights (or their illumination) if you can see from your bed. (If it’s an alarm clock, get rid of it entirely; clockwatching is a major insomnia inducer already.)
Nightlights can also be too bright for their intended use. Choose soft white light bulbs rather than bright LED bulbs. The purpose of the nightlight is to provide sufficient low-level light so you can be safe walking from your bedroom to your bathroom, or to allay a person’s fear of the dark. If you use LED bulbs to do this, you may as well just turn the lights on.
External light pollution
More on LEDs in this Washington Post article from last September:
“The American Medical Association issued a warning in June that high-intensity LED streetlights — such as those in Seattle, Los Angeles, New York, Houston and elsewhere — emit unseen blue light that can disturb sleep rhythms and possibly increase the risk of serious health conditions, including cancer and cardiovascular disease.”
The Law of Unintended Consequences strikes again, with whole cities facing decisions about scrapping their expensive investments in LEDs as a result.
But even standard streetlights using yellow sodium bulbs just outside your home could be too bright if they are close enough to your windows. So can neon lights. And urban centers tend to “glow” at night anyway, meaning that it can be impossible to achieve complete darkness in your sleeping space without investing in room darkening shades or light-blocking eye masks.
We aren’t talking about normal, ambient noise here.
Most people adjust to low amounts of background noise from their environments, whether it’s the whoosh of traffic from below one’s apartment building or the sound of coyotes howling out in the foothills.
Indeed, some people bring “noise machines” into their bedrooms in order to sleep better.
They choose between “colored” noises (like white or pink noise), or they select the sounds of ocean waves, falling rain, or crickets.
In fact, for people with tinnitus, background noise can make it possible for them to sleep at all.
(There are people who sleep with partners who use CPAP, and the soft hiss of that therapy is equally relaxing to their sleep, as well.)
There are other kinds of noise pollution that can wreak havoc on sleep, however.
- People who live near airports or military installations know the random roar of overhead commercial jets, fighter planes, or growlers.
- Those who live on the water by major seaports know first-hand how loud that stealthy aircraft carrier is, or the high-pitched whine of a submarine heading out to sea, or how loud cruise ships can be when the wind is right.
- Communities next to commuter or commercial rail lines can tell you all about the roar of trains passing by, or the sound of railroad crossing bells, or train whistles.
- Construction and industrial site noise shouldn’t be a problem due to ordinances about when work can take place, but it is. Urban industrial or traffic projects often employ workers overnight to prevent major commuting problems or to speed up completion of improvements. This can leave people sleepless at night listening to random, jarring noise.
- Household noises can include crying babies and noisy pets, televisions left on all night, the random sounds of plumbing or other building infrastructure, and cell phones that people forget to silence using built-in timers.
- Meanwhile, hospitals are among the worst offenders when it comes to noise pollution in public spaces, based on the presence of medical technology alarms alone.
- And then there are the noises of the terminally sleepless, as described by members of this small community in Sussex, which include the sounds of car horns, maxed out boom boxes, shouting voices, and playing kickball against residential building walls between the hours of 11pm and 3am.
Besides enforcing noise ordinances, there’s little one can do without approaching City Hall with demands. Wearing simple earplugs, using the aforementioned noise machine options, installing noiseproofing in your home, or trying some of the new wearable sleep devices which assist with comfortable noise cancellation are some options worth considering.
What about air pollution?
Our strides toward technological progress have a way of catching up with us in our very own homes.
Air pollution is a problem, no matter what time of day. For those who live in environments where the air is tainted by industrial or transportation particulates, trying to sleep at night can literally turn healthy people into asthmatics or, worse, lung cancer patients.
Part of the problem is that people frequently live for decades in an urban community which was not originally settled near the site of a factory of highway. But urban sprawl and changing economic trends mean that those who were there first are suddenly facing a decision to leave a community because of air quality concerns. Allergies and asthma become more prevalent, with both being major disrupters of nightly sleep.
The San Francisco Chronicle in January highlighted such concerns among residents of the Bayview District, who are dealing with pollutants from the diesel engines of truck drivers. Recently they posted dozens of “spare the air” signs prohibiting idling engines for more than five minutes due to the negative health impacts clinically associated with diesel exhaust.
Sleep and indoor air quality
New products to help analyze and correct the air quality of a home are on the rise as people become more wary of the effects of air pollution on their health. Beacon has minted a new UK-based Kickstarter campaign to create a light cube for better control over interior light which will also include an indoor air-quality tracker.
The reasoning? From the founder, Kingsley Hull: “There’s [outdoor] pollution in the air that’s killing us, but what I think people forget is that our indoor environment is ten times more polluted than outdoors.”
What’s polluting our household interiors? External pollution like ozone and particulates, but also internal pollutants like plastics (which can off gas), poorly circulated air with high CO2 levels, ordinary allergens like dust and cigarette smoke, and much more.
Poor air quality and sleep apnea
This isn’t an alarmist strategy to prompt unnecessary investment into clever new technology. Quite the opposite: A Journal of Thoracic Disease article in 2010 shows an inverse relationship between decreases in air quality and increases in sleep-disordered breathing. (Further reading here.)
“Particles may influence sleep through effects on the central nervous system, as well as the upper airways,” wrote Dr. Antonella Zanobetti, the study’s senior researcher at Harvard.
She and her team used data from the Sleep Heart Health Study, comprised of than 6,000 participants between 1995 and 1998, to arrive at their conclusions.
Zanobetti went on to say that “…Poor sleep [associated with poor health outcomes] may disproportionately afflict poor urban populations. Our findings suggest that one mechanism for poor sleep and sleep health disparities may relate to environmental pollution levels.”
For healthy people, these are problematic findings. But consider, too, the special needs of people using CPAP: their machines pull from “room air” to deliver pressurized therapy directly to their airways via a mask. Even while these machines use filters, it’s concerning that the very air they are using may already be toxic to begin with.
Let’s clean up our sleep
On this Earth Day, April 22 2017, please think about the critical importance of environmental health—toxic levels of light, noise, and particulate matter, especially—as it relates to your own ability to thrive as a human being.
There are important considerations we all must make about our sleep environments. Sleep is not optional, and the freedom to sleep in a healthy, sleep-inducing space is not a privilege, but a human right for every person on the planet, no matter where they live.