wavelength

Killing Blue

Killing Blue 0

My favorite color is down for the count. Blue might have been down longer than I realize. I’ve heard of blue blocker sunglasses a long time ago but I thought that might have just been a fad of some kind. Who knew what kind of studies there were that blame blue light for causing so much damage in the eye? I admit I’m still reading a lot of studies and articles trying to sort this out. I mean, can you look at the blue sky and ever think it’s bad? That’s what seems so wrong about this.

Let’s start with the bad news (but there is good news too). The other day I was a participant in a webinar. The topic was about this newly released product called Crizal Prevencia. Now I’m skeptical of products right off the bat because I usually only get the marketing spiel. This webinar spiel was no different. It’s a coating applied to lenses in glasses that is supposed to reduce by 20% the amount of blue light in the 415nm – 455nm range. Why is that range such a big deal? Well, that group of wavelengths is pretty near the ultraviolet wavelengths (UV-A) and you can pretty much guess something close to UV isn’t exactly considered healthy (or is it?). I’m sorry but I can just see it now. ¬†Opticians (I’m not accusing all of them) will be/are telling their customers that they need this coating because it can help prevent macular degeneration.

What is macular degeneration? It’s an eye disease in the macula, of course! The macula is this small part of our eye (in the back of our eye in the retina) that we see the best with….the 20/20 part of our vision. It’s also an age-related condition which in this case means it can occur when you’re old. UV exposure (I’ll get to blue light) apparently adds up and if you get too much of it over a life-time then you’re at greater risk of skin cancer and macular degeneration…and cataracts. I believe I read that blue light causes a cumulative effect in our retinas as well and studies show macular pigment and blue light are not very compatible. I tell ya, if it isn’t one thing that’s bad we have to go and blame the color blue now.

But there’s something more odd, but good, about blue light. Because there’s a range of other wavelengths that are still blue and some of that range is apparently beneficial. Doesn’t that just make this whole thing weird? Blue light in the range from 465nm – 495nm helps our circadian rhythm, memory and thinking. Older patients have even been told to wear glasses that allow that blue light to help with their sleep cycle. Yay for something good about blue light.

And here’s good news for those with blue eyes. Based on some studies, blondes and blue eyes are not any more prone to developing macular degeneration than¬†brown eyes. But you can also find articles reporting the opposite. Make up your minds people! It’s hard to find the definitive answers to anything sometimes. And here’s more good news (maybe). Once we get cataracts, blue wavelengths are absorbed in the cataract just like blue blocker glasses. So the studies about macular degeneration and blue are interesting to read. There just doesn’t seem to be clear explanations about how much blue light and at what age it does it’s most damage. Studies say it’s when we’re younger. Can you really imagine seeing all those kids playing soccer wearing sunglasses?

Since this article is partially about macular degeneration I wonder if we all start eating better, don’t smoke and don’t play too long at the pool everyday, will macular degeneration decline? There are genetic factors that contribute to a lot of diseases and that includes macular degeneration so we can’t eliminate that part just yet. Just don’t stare at bright lights too long and wear sunglasses and a hat and try to get your kids to as well.

Oh, will your computer users have any problems with blue light from the LCD‘s? Oh boy. Another issue for another day.

Here’s the visible spectrum again. Find your favorite shade of blue and see what wavelength it is.

spectrum

spectrum

 

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Woad, Ultramarine, Cobalt and Lapis, but no Ochre

Woad, Ultramarine, Cobalt and Lapis, but no Ochre 0

I was looking up blue pigments and found there are a lot of natural substances that have been used to create blue. I’m not going to go into the different substances just yet because after reading about some of these I wondered what was used in blue tattoos. They (any tattoo) are more popular than ever (makes me wonder if I’m in the minority). It seems that blue ink chemistries can vary and it looks like various forms of heavy metals are used. Cobalt is one pigment in blue tattoos. Cobalt is an element that is gray colored when pure (that’s not how we find it in nature) but in the oxide form it’s blue. Other blue inks in tattoos might have copper or iron oxides. Along with reading about blue ink in tattoos I found that the vehicle used in the injection can increase the systemic absorption of these metals. I believe a waiver is supposed to be signed before getting a tattoo? Good idea.

There are a lot of different things that were used and may still be used to make blue pigments and dye. The plant commonly called woad has leaves that can be boiled and then through certain steps a blue residue will result. Another plant dye, Indigo, also comes from a few different types of plants and was considered a luxury product by Greeks and Romans. These days our blue jeans are dyed with a synthetic indigo but I found there is a brand of denim called Momotaro in Japan that uses natural indigo dyes…and is quite pricey.

Other blue dyes and pigments come from mineral forms like ultramarine and lapis. Ultramarine was given it’s name because it was imported from over seas. Grinding the lapis into a powder and then combining it with another product can make blue paints or printing inks. Ultramarine can be found in cave paintings and Renaissance art and may have been used sparingly in some art because of it’s cost to produce. Synthetic ultramarine (aka, Prussian blue) may be found as a bluing agent in detergents which is interesting. The resultant effect of bluing is to make whites whiter through a subtractive coloring effect with the yellowing that occurs with white clothes. Azurite is another mineral with copper in it that was substituted for ultramarine because of it’s lower cost.

What about ochres? Well, they aren’t blue in color but they were and still are the basis for a lot of paintings. I live by a lot of red rocks in Colorado. That color and the variations of it is due to the iron content that has oxidized….rust basically. Ochre colors can be yellow, orange, red and somewhere in that range and can be found in modern paints and in cave paintings as long as 75,000 years ago.

By no means have I covered or could possibly cover all the blue pigments and dyes, nor the other basics used in making paint colors. But, I will pursue my education further in this area because….I can’t stop reading about all these fascinating things.

And you know why blue is blue, right? Well, if we’re not talking about blue sky and blue eyes and the Tyndall effect or emotion, we’re talking about about the physical effect of how the blue wavelength is reflected off the material. You could say the material isn’t blue, that it only reflects blue wavelengths….but then someone would look at you crazylike.

Momotaro jeans

Momotaro jeans

 

ochre in the arch

ochre color in the arch

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