The Dark Side of LED Lighting

April 26, 2024 10:43 PM

The global transition to LED lighting seems to be having some concerning impacts on the natural world and human health.
posted by blue shadows (18 comments total)

I am not an expert, but this seems misleading. As I understand it, yes, cool white mostly blue spectrum LEDs are the default, but warm white and full spectrum LEDs are also easily manufactured and widely available. And the issue of artificial light at night impacting plants and animals and insects has nothing to do with LED lighting in particular.

Perhaps someone who is more of an expert on LED tech will comment.
posted by Rhedyn at 1:37 AM on April 27 [6 favorites]

I think the problem is that even warmer, more natural color LEDs are still much bluer and less full spectrum, not mention expensive. LED lights are also dramatically increasing light pollution (sorry, can't find an ungated version).
posted by blue shadows at 1:47 AM on April 27 [3 favorites]

The last time (2019) I designed outdoor lighting LEDs available were still very peaky, nothing like full-spectrum, also there's a significant lag time between a lighting innovation and its availability to the outdoor lighting industry. And worst of all ime, is that to consumers (and electricians) 'lighting is lighting' and I've had several instance where my very carefully selected range of luminaires is swapped for cheaper ones.

The current state of the art willife response to lighting (including LED) is Travis Longcore's (USC) compendium of photopigment peak sensitivities and visual spectral response curves of terrestrial wildlife to guide design of outdoor nighttime lighting. This paper is very applicable to lighting design. Travis is arguably the lead in this area. I have met Travis irl.
posted by unearthed at 2:04 AM on April 27 [23 favorites]

Regardless of the spectrum it emits, the big problem with outdoor lighting is that there is too much of it leaking pollution into the air.

• When you need it, keep it low and aim it down.
• When you don't need it, which is probably most of the time, turn it off automatically.

If you're trying to deter intruders, use motion detectors to turn on the light and let the intruders know they've been detected and let you know something's moving in the area.
posted by pracowity at 2:30 AM on April 27 [20 favorites]

The full paper about light and blood glucose seems to be here. There's an abstract on PubMed.

I'm not confident on my ability to interpret it. It is a human study, they exposed people to the light and checked their glucose levels, it's not just something done to cells on a slide. Sample size isn't huge, 30 in total, 15 in the control group.

So, it's not like an "everybody panic" result, but interesting. I am wondering now how the change from incandescent bulbs maps to the rise in obesity over recent decades. Would be weird if after all the fusses about ultraprocessed food and protein leverage it turns out that the obesity crisis was actually all about light bulbs.

I think that the phase out of incandescent light bulbs was probably a bit too late for it to be a major factor though, the obesity crisis was well under way in the 1990s and the light bulb switchover only really got going in the mid 2000s.
posted by TheophileEscargot at 2:38 AM on April 27 [2 favorites]

I set up a small aquarium last year and was struck by the availability of fairly cheap LED lights that bathe the tank in dim red light to simulate dawn, bright full spectrum light at mid day and even a dim blue to give an impression of moonlight. I may live in Scotland but the fish could be forgiven for thinking they are in the Orinoco. It seems the lighting we expose ourselves to could maybe draw some lessons from this approach.
posted by rongorongo at 2:54 AM on April 27 [5 favorites]

LED light spectrum database, based on actual tests of the lights instead of just spec sheets. The best results from the tests, along with comparisons to the spectrum of sunlight. Reddit post by the creator.
posted by clawsoon at 4:38 AM on April 27 [14 favorites]

I am baffled why the LED test database clawsoon linked omits IKEA, a leader in retail LED bulbs and fixtures.
posted by seanmpuckett at 5:30 AM on April 27 [1 favorite]

Oh, we've always known that LED lighting is bad for you. Everyone knows it's bad for the environment, too! That's why we're switching back to clean, reliable gas lighting.
posted by phooky at 5:41 AM on April 27 [23 favorites]

I am baffled why the LED test database clawsoon linked omits IKEA, a leader in retail LED bulbs

As far as I can tell this is just a few people doing this as a hobby. I couldn't find if their selection criteria exactly but if you look at the list of bulbs tested and the change history, it's clear they have some -- it's not entirely quick/easy/cheap to add lots of new bulbs, and it seems a bit wrong to bash them for it. (Also, there was enough info at various links to replicate the methods if one wanted.)
posted by advil at 6:24 AM on April 27 [1 favorite]

People buy overly blue LED bulbs for the same reason they used to buy cool white incandescent bulbs. It's just what they like.

Happily, warm white LED bulbs are readily available. It's been a while since I last bought new bulbs, but a couple of years ago it was pretty hard to find low CRI LED bulbs of any color temperature.

Most of my lights have RGBWW smart bulbs in them. Yes, two different white channels, one very warm white and one very cold white, so they can manage a color temperature anywhere between about 2500K and 6500K with a nice wide spectrum. Outside that range they have to use some red and green or a touch of blue to fake the color temperature. Looks nice at first glance, but can be tiring on the eyes after a while, same as any low CRI bulb.

As far as outdoor lighting goes, the city I live in now just got around to replacing the HPS lamps on the road in front of my place. They went with a color temperature much warmer than what Miami did some years back when I was still living there. These new ones almost look a bit pinkish to me.

My only complaint is that they are unnecessarily bright. Not overpoweringly so as I've seen elsewhere, but still more than is required for street lighting. Not that this is anything new. Cities just can't help but throw enough light to cast deep shadows. They've been doing it since public lighting first became a thing with moon towers, though the mercury vapor lamps gave us a bit of a reprieve for a while. It came roaring back with the sodium lamps and hasn't abated a bit since.
posted by wierdo at 6:29 AM on April 27 [1 favorite]

Here is an article in LED Professional by Travis Longcore as referenced by unearthed above, Hazard or Hope? LEDs and Wildlife.

Quoting the conclusion: The efficiency benefits of LEDs and the resulting economic incentives will drive further conversion of outdoor and indoor lighting to the technology. If the tendency to light more when light is cheaper can be overcome, the other attributes of LEDs hold significant promise for reducing environmental effects. Realizing that promise requires designers and manufacturers to learn about and embrace the guidance that wildlife scientists can provide. In some instances it will be challenging - resisting the desire to up-light, using no more light than necessary, and educating clients on the benefits of spectral choices that do not look like daylight. In other contexts, environmental regulations are likely to dictate lighting choices and offer an opportunity if the industry is prepared to seize it. On each of the mitigation approaches - duration, direction, intensity, and spectrum - LEDs will inherently or can be designed to perform well. Whether they do in practice will be up to the LED professional.

So I continue to think that articles that make blanket statements about LEDs as if they were all blue light are misleading (and make me suspicious given the history of weird politicisation of lightbulbs), since this article points out the ways that LEDs, if their flexibility is utilised, can be helpful to reduce effects on wildlife rather than harmful.
posted by Rhedyn at 7:09 AM on April 27 [4 favorites]

Here's the Washington Post piece blue shadows posted ungated.
posted by swerve at 7:11 AM on April 27

My complaint is that I can’t find bright bulbs to light my reading. LED bulbs, though supposedly the same as a 100 watt incandescent bulb seem really dim to me. Should I try to get an LED streetlight bulb given that all the comments here seem to suggest that they are too bright?
posted by njohnson23 at 8:59 AM on April 27

This article reminds me of how you always get enough stories to fill “the news hole,” except here it’s combined with enough papers to fill the paper hole.

I guess it’s possible there’s some link between LED lighting and low-level metabolism, but my woo-woo alarm is blaring. For some reason it doesn’t like “ Journal of Biophotonics” much. Or tiny studies reported breathlessly. Maybe it’s just to early in the morning for me.
posted by Gilgamesh's Chauffeur at 9:21 AM on April 27 [8 favorites]

International Dark Sky Association (originally founded by astronomers but now a broader coalition) on responsible outdoor lighting
posted by neuron at 11:05 AM on April 27 [7 favorites]

There's a guy on linked in taking remote data entry position applications. It seems this is his area of research. I've been so so so curious to apply and then see if they reject me for using LED lights in my own apartment.
posted by symbioid at 11:18 AM on April 27 [1 favorite]

I don't know what my city did, but our streetlights don't emit very much light at all, and ththat's a real problem for pedestrians crossing streets at night. As a driver in a car, I can barely see them in the crosswalk. I assumed they transitioned to LEDs and that they're just not as bright.
posted by vitabellosi at 1:11 PM on May 1