Anyone who knows me knows I’m not a morning person. I recently woke up late in the night with my mind momentarily tricked into thinking it was morning by the light creeping in between my drapes. This happens on many-a-night, but this time I had an “a ha!” moment. LIGHT POLLUTION. Could light be disrupting my sleep?
In my quest for better sleep I decided to investigate, and I learned that light most certainly has a profound effect on our sleep patterns.
Most of us have heard of blue blocker glasses which are supposed to reduce eyestrain. Some sleep scientists and experts recommend wearing blue blockers for two hours preceding bedtime to ensure quality sleep. The more I researched this topic the more evidence I found that light, blue light especially (450-495nm), is extremely disruptive after the sun goes down.
Sidetracked: I wonder how well my blue-blockers actually work? I decided to put it to the test by measuring my monitor and comparing it to the transmission of my glasses using a BLUE-Wave spectrometer, fiber, and collimating lens for collection:
I thought my Blue-Blockers would block more blue than this. They’re only reducing blue light by ~15%.
Blue light can lead to serious problems with insomnia, disrupt hormone production by preventing deep sleep cycles, strain our eyes, disrupt melatonin production, and more. Common blue light emitting culprits are computer screens (as we just saw), TV’s, and phones. More recently I noticed this extends beyond those household culprits to vehicles, streetlights, storefronts, and advertisements.
Streetlights and vehicle lights have allowed us to extend our days well into the night. Industrial lights provide visibility and safety, and advertisements are no longer restricted to daytime. This can be great sometimes, but all these unnatural sources of light have eliminated much of our natural nighttime experience. As we push dark skies further and further from population centers, there are some huge drawbacks. Similar to TV’s and computer monitors, street and outdoor lights also adversely affect our health and sleep patterns. We no longer take our bedtime cues from the setting sun. We can no longer connect with nature by gazing up into the starry night which can be meditative and give us perspective when we can actually see and appreciate the immensity of our universe.
Just like for us humans, wildlife is adversely affected by artificial light. I remember an experience from when I was studying at University that really drove this point home for me. I recall tracking the nesting habits of sea turtles. There was strong concern that the sea turtles may hatch at night and rather than following moonlight into the sea, they would follow the artificial streetlights in the wrong direction where they would die, sometimes by being run over.
This is just one example but there are many more. Mammals, reptiles, birds, insects are dependent upon the day/night cycle. They all rely upon the dawn and twilight queues to effectively compete in their ecosystems and sleep just like us. Growth, development, reproduction, resource gathering, and locomotion are all tied to the natural balance between day and night. So, what about my street and the lights that disrupt my sleep?
I recently noticed the county has been replacing our standard high-pressure sodium lights with a new kind of light … LED induction lamps! In my humble opinion, they are too blue and too bright, but I have a hunch they are objectively so.
Driven to insanity by a lack of sleep, I decided to make use of the midnight hours by making some measurements comparing the streetlights in my neighborhood.
As suspected, these new streetlamps are emitting 10x’s more in the blue portion of the spectrum.
It’s time to invest in some nifty night shades and write a letter to the county.
