blue light associated with prostate and breast cancer

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Mark M
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15% of 2 mg would be 0.3mg or 300 micrograms, you used the phrase “massive overdoses” which implied that there are significant side effects from taking such a dose. That is absolutely incorrect. I would also say correlation is not causation and the only people drawing incorrect conclusions are those in this thread.

hank
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If you want a deep dive into weighing the risk factors, this paper and those it cites will be a good start; click through for the cited sources.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6071739/

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I think studies of the effect of blue (or other) light sources on melatonin production and the relation of melatonin levels vs risk for these types of cancers is needed to see the whole picture.

That study simply shows a correlation between “ALAN” and cancer rates vs the whole causal chain.

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hank wrote:
If you want a deep dive into weighing the risk factors, this paper and those it cites will be a good start; click through for the cited sources. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6071739/

Any study that primarily relies on self reporting is inherently flawed and if you don’t get that then there is no hope in me continuing to argue here.

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Yep. Put those questions into Google Scholar and you’ll find much of the work you wish for has been done and published.
https://scholar.google.com/scholar?hl=en&as_sdt=0%2C5&q=melatonin+level+...

I’m not going to try to summarize the field here, though. I’m just a casual reader like yourself, albeit with a bent toward looking things up in Google Scholar.

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Mark M wrote:

The risk that this poses for you to develop cancer has to be so small as to be almost infinitesimal. You are far more likely to develop a form of cancer from chemical exposure or other environmental/epigenetic factors.
Thumbs Up

Mark M wrote:

This thread needs to die.
Expose it to mass quantities of ‘Blue Light’… that will kill it post haste. . Wink

Mark M wrote:

Do you understand the concept of bioavailability? Or first pass metabolism?
Exactly….. Thumbs Up . For any that do not understand, "you can look this stuff up". Google be ur’ friend…. Wink

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jon_slider wrote:
pinkpanda3310 wrote:
It rests on my bedside draw and is possibly my most used light as I don’t always sleep well.

very cool

do you think blue light could be keeping your melatonin suppressed?

Im interested in trying Red Trits


My wife is a clean freak and as a result the light lives ‘in’ the draw instead of on top now.

If you’re asking if I felt affected by the blue light and my sleep then no, there are many other factors that have a far greater impact on my sleep pattern. Besides I honestly think the low output of trits and glow have much less impact than other sources of light in everyday life e.g. room lighting, phones, pc’s…. etc…

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Man….is it really matters? I’ve lived throughout the periods of incans, neon sticks, CFL, and now LED. I put whatever lights available in any of my rooms. None of them disrupts my cycle. When I feel sleepy I just sleep. I can easily sleep and drool in my class room, bus, closet, etc… no problem.
Perhaps I have no sensitivity at all?

What really disrupts my sleep cycle is BLF, and I enjoy it. Believe it or not.

[Clemence]

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I’m stuck doing on-call work, so why not get my hands dirty in a science thread…

SKV89 wrote:
Actually blue light has been known to be carcinogenic

That’s not quite an accurate way to put it. Studies show an association, but the specific cause is not clearly known. The leading theory is the effect is secondary or tertiary due to reduced melatonin production or the reduced amount and quality of sleep that results. There are still lots of open questions.

For example, the methodology of the study Jon posted would be extremely susceptible to confounding factors like there being more LED lights in urban areas, but also more air pollution.

wle wrote:
there is blue light in sunlight… is that causing all these symptoms?

Doubtful. This is one of the problems I have with news reports on most blue light studies (just the news reports, not the studies themselves). They typically fail to clarify that we’re exposed to far, far higher intensities of blue light during the day than what most of these studies look at, which in the latter case is primarily light exposure during our sleeping hours.

Dougiestyle wrote:
The liberal use of the word “may” negates the declaration of a scientific conclusion. H2O “may” be lethal… Circumstances dictate how lethal.

The scientists didn’t say “may.” They said there was an association in the data they collected. A newspaper reported that as “may increase the risk of cancer,” which is not unreasonable speculation, but it’s also not very concrete.

DominikM wrote:
The main issue here is a blue light spike at 430-440nm – it’s caused by a phosphor coating quality and phosphor’s mix.

As you can see not only CCT matters, the 4000K cannot be named “safe” or “safer”

The research I’ve found does not agree with you. Color temperature does appear to matter with melatonin suppression at 3900K roughly half that at 6100K. And brightness is at least as much of a factor as color temperature. All of the tests in that study were done at typical office light intensities, except the control was just enough room to find one’s way around.

I’ve not seen any research specific enough to identify the spike at pump emitter’s peak as a specific issue.

There has actually been some research suggesting mixed light causes less melatonin suppression than blue light alone.

Lightbringer wrote:
No such thing as a “Lee minus blue” filter or nuttin’?

Lee 821. As you can probably guess, it will reduce output a modest amount, and visibly change the tint to be more golden.

optosolis wrote:
thanks , – so what do you use daytime use?. I have a 5600k E21A for daytime use. I am even considering 3000 or 2000k for daytime use to be safe.

I see no reason to think a daylight tint like 5600K is a concern for daytime use. 3000K, being a big mismatch in color temperature to the normal ambient source, is not very appealing to me during the day, although I really like it around the house at night.

hank wrote:
If you want a deep dive into weighing the risk factors, this paper and those it cites will be a good start; click through for the cited sources. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6071739/

That is the same study Jon linked to in the first post, just hosted on a different site.

Mark M wrote:
Any study that primarily relies on self reporting is inherently flawed

Limited, not flawed. Questionnaires are a common tool for studies on topics for which measurements are impractical, but obviously, well-chosen questions are critical.

In this case, for indoor light level while sleeping, they asked a fuzzy question with 4 possible answers, with the assumption that variation in how different people responds tends to average out in large groups. For outdoor light level, they used measured data. They evaluated both factors separately. Both demonstrated an association.

It is worth noting, however, that the measured data analysis showed a lower association (but still an odds ratio higher than 1) than the self-reported data analysis.

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Fwiw, melatonin puts me under and NicOH keeps me under.

Melatonin will start to give me the fuzzies in about 20min, but if I force myself to stay awake through that, forget it. Not even another hit would put me under.

Also, chances are a few hours later when it wears off, I wake up. Hence the NicOH (niacin, 1g) to keep me under.

Best is to just stay “regular”, keep things dark, find something boring to think about.

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I take Time Release melatonin.

It helps me fall sleep, and I stay asleep.

(Regular melatonin doesn't keep me asleep.)

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Nev wrote:

WARNING


reading this thread my cause cancer or worse still it may overstimulate your  hypochondria.

Single most well thought out post I have read on this thread. Bravo.

"Everywhere I go, there I am"

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/\ Amen…. Wink

Read this thread & you’d think ‘BLF’ stood for Blue Light Fear. . Big Smile

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And because blue light is a next-of-kin to UV light, keep your pants on when hunting for scorpions at night.

You are a flashaholic if you are forced to come out of the closet, to make room for more flashlights.

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So, what do we actually take away from all this??

  • 1. Blue Light DOES NOT cause cancer.
    ………a. It does/can affect sleep patterns, which in turn affects Melatonin/hormone production; which may make us more prone to develope certain type cancers.
  • 2. Is this cause for mass hysteria & wide scale panic??
    ……….a. NO
  • 3. What can we do to possibly avoid this potential ‘Blue Light Death Trap Phenomenon’?? [‘BLDTP’ for short…. Wink ]
    Well, without getting overly crazy about it; we can do the common sense things sbslider, pinkpanda3310, & a few others have mentioned:
    …………. a. Limit computer, phone, & screened device use a couple of hours before bed.
    …………. b. Have a fairly routine sleep time in a dark place. A very faint night light will not hurt…. even if it is Blue most likely.
    …………. c.‘Don’t Worry, Be Happy’….. Thumbs Up
    ____

The article below from Harvard Medical School is interesting.

Harvard Health Publishing

Harvard Medical School

https://www.health.harvard.edu/staying-healthy/blue-light-has-a-dark-side

Harvard Health Letter

Blue light has a dark side

What is blue light? The effect blue light has on your sleep and more.

Updated: August 13, 2018 ……. Published: May, 2012

Although it is environmentally friendly, blue light can affect your sleep and potentially cause disease. Until the advent of artificial lighting, the sun was the major source of lighting, and people spent their evenings in (relative) darkness. Now, in much of the world, evenings are illuminated, and we take our easy access to all those lumens pretty much for granted.

But we may be paying a price for basking in all that light. At night, light throws the body’s biological clock—the circadian rhythm—out of whack. Sleep suffers. Worse, research shows that it may contribute to the causation of cancer, diabetes, heart disease, and obesity.

What is blue light?

Not all colors of light have the same effect. Blue wavelengths—which are beneficial during daylight hours because they boost attention, reaction times, and mood—seem to be the most disruptive at night. And the proliferation of electronics with screens, as well as energy-efficient lighting, is increasing our exposure to blue wavelengths, especially after sundown.

Light and sleep

Everyone has slightly different circadian rhythms, but the average length is 24 and one-quarter hours. The circadian rhythm of people who stay up late is slightly longer, while the rhythms of earlier birds fall short of 24 hours. Dr. Charles Czeisler of Harvard Medical School showed, in 1981, that daylight keeps a person’s internal clock aligned with the environment.

Is nighttime light exposure bad?

Some studies suggest a link between exposure to light at night, such as working the night shift, to some types of cancer, diabetes, heart disease, and obesity. That’s not proof that nighttime light exposure causes these conditions; nor is it clear why it could be bad for us. But we do know that exposure to light suppresses the secretion of melatonin, a hormone that influences circadian rhythms, and there’s some experimental evidence (it’s very preliminary) that lower melatonin levels might explain the association with cancer.

A Harvard study shed a little bit of light on the possible connection to diabetes and possibly obesity. The researchers put 10 people on a schedule that gradually shifted the timing of their circadian rhythms. Their blood sugar levels increased, throwing them into a prediabetic state, and levels of leptin, a hormone that leaves people feeling full after a meal, went down.

Even dim light can interfere with a person’s circadian rhythm and melatonin secretion. A mere eight lux—a level of brightness exceeded by most table lamps and about twice that of a night light—has an effect, notes Stephen Lockley, a Harvard sleep researcher. Light at night is part of the reason so many people don’t get enough sleep, says Lockley, and researchers have linked short sleep to increased risk for depression, as well as diabetes and cardiovascular problems.

Effects of blue light and sleep

While light of any kind can suppress the secretion of melatonin, blue light at night does so more powerfully. Harvard researchers and their colleagues conducted an experiment comparing the effects of 6.5 hours of exposure to blue light to exposure to green light of comparable brightness. The blue light suppressed melatonin for about twice as long as the green light and shifted circadian rhythms by twice as much (3 hours vs. 1.5 hours).

In another study of blue light, researchers at the University of Toronto compared the melatonin levels of people exposed to bright indoor light who were wearing blue-light–blocking goggles to people exposed to regular dim light without wearing goggles. The fact that the levels of the hormone were about the same in the two groups strengthens the hypothesis that blue light is a potent suppressor of melatonin. It also suggests that shift workers and night owls could perhaps protect themselves if they wore eyewear that blocks blue light. Inexpensive sunglasses with orange-tinted lenses block blue light, but they also block other colors, so they’re not suitable for use indoors at night. Glasses that block out only blue light can cost up to $80.

LED blue light exposure

If blue light does have adverse health effects, then environmental concerns, and the quest for energy-efficient lighting, could be at odds with personal health. Those curlicue compact fluorescent lightbulbs and LED lights are much more energy-efficient than the old-fashioned incandescent lightbulbs we grew up with. But they also tend to produce more blue light.

The physics of fluorescent lights can’t be changed, but coatings inside the bulbs can be so they produce a warmer, less blue light. LED lights are more efficient than fluorescent lights, but they also produce a fair amount of light in the blue spectrum. Richard Hansler, a light researcher at John Carroll University in Cleveland, notes that ordinary incandescent lights also produce some blue light, although less than most fluorescent lightbulbs.

Protect yourself from blue light at night

Use dim red lights for night lights. Red light has the least power to shift circadian rhythm and suppress melatonin.

Avoid looking at bright screens beginning two to three hours before bed.

If you work a night shift or use a lot of electronic devices at night, consider wearing blue-blocking glasses or installing an app that filters the blue/green wavelength at night.

Expose yourself to lots of bright light during the day, which will boost your ability to sleep at night, as well as your mood and alertness during daylight.

You never know how a horse will pull until you hook him up to a heavy load./"Bear" Bryant 

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Mark M
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iamlucky13 wrote:
I’m stuck doing on-call work, so why not get my hands dirty in a science thread…
SKV89 wrote:
Actually blue light has been known to be carcinogenic

That’s not quite an accurate way to put it. Studies show an association, but the specific cause is not clearly known. The leading theory is the effect is secondary or tertiary due to reduced melatonin production or the reduced amount and quality of sleep that results. There are still lots of open questions.

For example, the methodology of the study Jon posted would be extremely susceptible to confounding factors like there being more LED lights in urban areas, but also more air pollution.

wle wrote:
there is blue light in sunlight… is that causing all these symptoms?

Doubtful. This is one of the problems I have with news reports on most blue light studies (just the news reports, not the studies themselves). They typically fail to clarify that we’re exposed to far, far higher intensities of blue light during the day than what most of these studies look at, which in the latter case is primarily light exposure during our sleeping hours.

Dougiestyle wrote:
The liberal use of the word “may” negates the declaration of a scientific conclusion. H2O “may” be lethal… Circumstances dictate how lethal.

The scientists didn’t say “may.” They said there was an association in the data they collected. A newspaper reported that as “may increase the risk of cancer,” which is not unreasonable speculation, but it’s also not very concrete.

DominikM wrote:
The main issue here is a blue light spike at 430-440nm – it’s caused by a phosphor coating quality and phosphor’s mix.

As you can see not only CCT matters, the 4000K cannot be named “safe” or “safer”

The research I’ve found does not agree with you. Color temperature does appear to matter with melatonin suppression at 3900K roughly half that at 6100K. And brightness is at least as much of a factor as color temperature. All of the tests in that study were done at typical office light intensities, except the control was just enough room to find one’s way around.

I’ve not seen any research specific enough to identify the spike at pump emitter’s peak as a specific issue.

There has actually been some research suggesting mixed light causes less melatonin suppression than blue light alone.

Lightbringer wrote:
No such thing as a “Lee minus blue” filter or nuttin’?

Lee 821. As you can probably guess, it will reduce output a modest amount, and visibly change the tint to be more golden.

optosolis wrote:
thanks , – so what do you use daytime use?. I have a 5600k E21A for daytime use. I am even considering 3000 or 2000k for daytime use to be safe.

I see no reason to think a daylight tint like 5600K is a concern for daytime use. 3000K, being a big mismatch in color temperature to the normal ambient source, is not very appealing to me during the day, although I really like it around the house at night.

hank wrote:
If you want a deep dive into weighing the risk factors, this paper and those it cites will be a good start; click through for the cited sources. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6071739/

That is the same study Jon linked to in the first post, just hosted on a different site.

Mark M wrote:
Any study that primarily relies on self reporting is inherently flawed

Limited, not flawed. Questionnaires are a common tool for studies on topics for which measurements are impractical, but obviously, well-chosen questions are critical.

In this case, for indoor light level while sleeping, they asked a fuzzy question with 4 possible answers, with the assumption that variation in how different people responds tends to average out in large groups. For outdoor light level, they used measured data. They evaluated both factors separately. Both demonstrated an association.

It is worth noting, however, that the measured data analysis showed a lower association (but still an odds ratio higher than 1) than the self-reported data analysis.

The study accounts for various risk factors by using self reported data from a 52 page questionnaire. You should know that the bias from that data set makes this study flawed. The shear number of studies that have had the hypothesis disproven because of self reported data is mind boggling. I will leave it at that.

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BurningPlayd0h wrote:
Since I haven’t read through the whole study itself, is that isolating this particular risk factor? News articles on medical studies have a LONG history of misinterpreting correlation as causation and ignoring any of the other research that shows they can’t study just one variable’s effects.

+100

Yes, forget about science news articles. They misreport what the studies conclude just as often as they get it right. They’re far more interested in clicks than they are interested in accurate reporting.

Go directly to the study. Make sure it is published in a well-respected peer-reviewed journal. Anything else is junk, and likely just a company doing fake studies just to sell you stuff.

Ideally, find a study that has been replicated, which helps eliminate p-hacking effects. A single study on its own, often later turns out to be false. And beware that statistically significant does not necessary mean it has a meaningful effect.

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teacher wrote:
Read this thread & you’d think ‘BLF’ stood for Blue Light Fear. . Big Smile

Wait… it doesn’t??

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I’m finding this thread interferes with my sleep.

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Lightbringer wrote:
teacher wrote:
Read this thread & you’d think ‘BLF’ stood for Blue Light Fear. . Big Smile

Wait… it doesn’t??

Warm white gang, RISE UP

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DominikM wrote:
Maybe I’ll show you some example – from photobiological safety point of view.

The main issue here is a blue light spike at 430-440nm – it’s caused by a phosphor coating quality and phosphor’s mix.

As you can see not only CCT matters, the 4000K cannot be named “safe” or “safer” sorry SKV89 ;).

Yea I no longer use 4000K for my night time EDC. After over a year of experimenting with different night time lights before sleep and its effect on how easy it is for me to fall asleep, I’m now using only 2700K and under. When I started using the E21A 2500K mixed tint as a ceiling bounce lamp, I started actually falling asleep while watching TV! Previously with my higher temp lights (brighter though) I don’t get sleepy and it takes me longer to fall asleep. 4000K and cooler lights also help me stay awake at night so I like them in the day time.

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jon_slider][quote=DominikM wrote:

I want to learn more about how to determine the RG0 Blue Light safety requirement.

do High CRI LEDs score better than Low CRI?
does low Color Temperature score better?
etc

In general, warmer color temps emit less blue wavelength versus cooler color temps. Also high CRI and R9 lights in general, to a lesser extent, emits less blue wavelength because the thicker phosphor converts more of the base blue light into other wavelengths to create warmer and higher CRI light, which allows less blue light to escape unconverted. The blue wavelengths that did not get converted through the phosphor are the “potentially” health concerning portion of the light.

For example, comparing 4000K XP-L HI 70CRI vs 4000K SST-20 95CRI, the XP-L HI produces (visually estimated from spectral graph) 20% more blue light with a much taller blue peak. I have been doing a lot of testing with my spectrometer lately so the above generalization is true for “most” cases however I find sometimes HI CRI of same CCT can produce more blue light than lower CRI of the same CCT. Also I’ve seen lights measuring the same color temp and similar CRI can vary significantly in the amount of blue intensity. So without testing the specific emitter, the above generalization is not an absolute rule.

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I’m glad somebody is paying attention to the science.

Chronobiol Int. 2012 Jun;29(5):641-9. doi: 10.3109/07420528.2012.675850.
Assessment of a new dynamic light regimen in a nuclear power control room without windows on quickly rotating shiftworkers—effects on health, wakefulness, and circadian alignment: a pilot study.

https://www.ncbi.nlm.nih.gov/pubmed/22621361

Quote:
The illumination level in a control room without windows at a nuclear power station was ~200 lux (straight-forward horizontal gaze) using a weak yellow light… the new light treatment increased alertness during the 2nd night shift …. it seems that appropriate dynamic light in rooms without windows during the dark Nordic season may promote alertness, sleep, and better adaptation to quickly rotating shiftwork.

Keeping nuclear power plant night shift operators alert — it’s a good idea.
Who designed the original windowless dimly lit control room?

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The American Optometric Association has also commented on the above-mentioned Spanish study:
http://www.aoa.org/news/clinical-eye-care/blue-lights-link-to-prostate-a...

Quote:
“Bottom line: Sleeping, especially for men, should occur in a room with no more than dim light.”

And on other research on the direct photochemistry (this is energy delivered by the high energy blue photons directly to the retina, unrelated to the melatonin/cancer issue)

Quote:
Blue light, high-energy wavelengths of light between 420 and 480 nm on the visible light spectrum, naturally suppresses the body’s melatonin production, boosting alertness and attention; however, after sundown, this effect can disrupt the body’s circadian rhythm. That’s why the advent of high-energy artificial lighting and digital screens has drawn scrutiny and even the implication that it could do more harm than good.

Hence, blue light exposure remains an open-ended clinical question that chemists at The University of Toledo (UT) sought to address. Per their study, researchers examined how blue-light-excited retinal (vitamin A aldehyde) triggered cytotoxicity in the retina, killing the photoreceptor cells that signal the brain. Once those photoreceptor cells die, they cannot regenerate much in the same way as AMD.


https://www.aoa.org/news/clinical-eye-care/blue-light-transforms-molecules-

http://utnews.utoledo.edu/index.php/08_08_2018/ut-chemists-discover-how-...

I noticed my eye doctor no longer uses a blue examination light for a long period of time when looking at my retinas, instead they use a yellow light that briefly changes to blue. I read of a couple of cases of blindness where a blue examining light was mistakenly left on too long.

More research https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5854379/
PLoS One. 2018; 13(3): e0194218.
Published online 2018 Mar 15. doi: 10.1371/journal.pone.0194218
PMCID: PMC5854379
PMID: 29543853
Removal of the blue component of light significantly decreases retinal damage after high intensity exposure

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6288536/
Int J Ophthalmol. 2018; 11(12): 1999–2003.
Published online 2018 Dec 18. doi: 10.18240/ijo.2018.12.20
PMCID: PMC6288536
PMID: 30588436
Research progress about the effect and prevention of blue light on eyes

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SKV89 wrote:
The blue wavelengths that did not get converted through the phosphor are the “potentially” health concerning portion of the light.

Maybe The Seoul Sunlike (mid power) LED might interest you.

Tally-ho wrote:
I’m really looking forward to Seoul Sunlike LED for household lights or something equivalent without a blue spike for NW and CW high CRI.


jon_slider
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hank wrote:

LOL!
thanks for your contributions Smile

.

SKV89 wrote:
For example, comparing 4000K XP-L HI 70CRI vs 4000K SST-20 95CRI, the XP-L HI produces (visually estimated from spectral graph) 20% more blue light with a much taller blue peak. I have been doing a lot of testing with my spectrometer lately
very helpful, thanks

so, do you have any quantifyable blue light levels data for
an Incandescent, and the
sw45k N219b 9080, and the
sw35 9080, and the
E21a 3000k, and the
Optisolis 6500k (I expect this one is best used as a worklight, when staying awake is desireable)

fwiw, my computer and iPhone have NightShift enabled, and my house lights are incandescent

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jon_slider wrote:

so, do you have any quantifyable blue light levels data for
an Incandescent, and the
sw45k N219b 9080, and the
sw35 9080, and the
E21a 3000k, and the
Optisolis 6500k (I expect this one is best used as a worklight, when staying awake is desireable)

bob_mcbob tested the Nichia 219B in a FW3A, if you look at his TM-30 tests you will see that it has a blue spike.
You will find the spectral power distribution of the E21A 3000K and optisolis 6500K on clemence’s website or here for the E21A and here for the optisolis (see imgur link in the message). The 6500K has a lot of blue which is not surprising since it is made to be as close as possible as the reference (D65 standard) which is daylight (above BBL).
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Tally-ho wrote:
bob_mcbob tested the “Nichia 219B in a FW3A”… it has a blue spike.

thank you

since the N219b is rated for no blue light hazard, the presence of a blue spike is not sufficient info

Im looking for reference number values,
so we can begin to have a conversation about
How Much blue light is being produced

as pinkpanda pointed out, the amount of blue light from a blue tritium for example, may or may not have enough output to impact melatonin and suppress sleep, I do not know

I need numbers.. like

X blue units from a N219b is Not capable of suppressing melatonin
while
Y blue units from a cool white fluoro IS capable of suppressing melatonin

etc
numbers so I can compare the relative blue outputs, and numbers that tell me a threshhold value for the “no Blue Light Hazard” designation

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I see what point you’re trying to make, but ‘directly causally linked to’ doesn’t make any sense, so that’s not what the article is saying

Bored anesthesia resident

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jon_slider wrote:
Tally-ho wrote:
bob_mcbob tested the “Nichia 219B in a FW3A”… it has a blue spike.

thank you

since the N219b is rated for no blue light hazard, the presence of a blue spike is not sufficient info

Im looking for reference number values,
so we can begin to have a conversation about
How Much blue light is being produced

as pinkpanda pointed out, the amount of blue light from a blue tritium for example, may or may not have enough output to impact melatonin and suppress sleep, I do not know

I need numbers.. like

X blue units from a N219b is Not capable of suppressing melatonin
while
Y blue units from a cool white fluoro IS capable of suppressing melatonin

etc
numbers so I can compare the relative blue outputs, and numbers that tell me a threshhold value for the “no Blue Light Hazard” designation


I don’t know how one could segregate blue light from a given light source and calculate the levels of effect? Especially when “light of any kind can suppress the secretion of melatonin”. Imagine slowly turning on one of your rrt-01 lights. At which point does the light have an affect?

If the study that teacher linked was correct – “Even dim light can interfere with a person’s circadian rhythm and melatonin secretion. A mere eight lux —a level of brightness exceeded by most table lamps and about twice that of a night light—has an effect” Then what?? Lower the light level by a quarter of a lux and you’re golden right Innocent YehNO , as always life is messier than that.

This discussion is like saying don’t eat hamburger and chips because it’s unhealthy. If it was the only thing you ate then yes unhealthy. If it was mixed in with a regular half healthy diet then you couldn’t pin point that as being the major factor for being overweight. More likely the lack of exercise is the reason which totally gets ignored because it’s too hard.

I understand some people like to go over the science of it all but really, who is going to change their lifestyle because of the Blue Light Fear . Turn the house lights down dim in the evenings and don’t look at screens 2-3hrs before sleep.

EDIT- Looking at my last sentence makes me wonder if that has anything to do with the world population growth rate slowing down LOL LOL LOL or am I reading into that too much? LOL

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