In the 1980s I remember seeing articles and news reports blaming Cool White Fluorescent lamps for causing skin cancer, eye damage, and depleting vitamin D from milk on store shelves. The reports said people should only purchase milk in cardboard cartons because it blocked the light. It was recommended that people change all fluorescent lamps in the home to other colors. I was told the schools in my area wouldn't use Cool White because it was bad for the eyes. Is there any truth to this? Almost all the lighting in my house is produced by older Cool White lamps. Should I worry?

no need to woory thats just common quackery,the people that said this want you to think that,theres no way color tempature of lighting can cause cancer or deplete vitiman d from milk.

It's not so much the color temperature itself. Fluorescent lights emit some UV rays which can degrade milk and theres a theory it could increase the risk of cancer, but its mainly when one is within 12 inches of the tube itself. So generally, no worries. Also I suspect some of the complaints are actually caused by the 60 hz flicker in magnetic rapid start ballasts. Preheat Tulamp lead-lag ballasts filter most of this flicker because the two tubes operate out of phase. Hope this helps!

It's not so much the color temperature itself. Fluorescent lights emit some UV rays which can degrade milk and theres a theory it could increase the risk of cancer, but its mainly when one is within 12 inches of the tube itself. So generally, no worries. Also I suspect some of the complaints are actually caused by the 60 hz flicker in magnetic rapid start ballasts. Preheat Tulamp lead-lag ballasts filter most of this flicker because the two tubes operate out of phase. Hope this helps!

In the same token, can running an MV lamp indoors be somewhat hazardous if you are within a couple of feet of it?

Yes, but only if it is a clear lamp, with no glass cover, and is made from quartz. If used in a fixture with an ordinary tempered glass cover, or laminated soda glass, the UV is greatly attenuated. The glass of the envelope also attenuates. Thus your exposure will be the same as if you are sitting in a sunny spot where sunlight falls on you though a closed window. You have the same risk if you are in the room during the day and are in full sunshine though the glass. There is a much higher risk from VOC emissions from your furniture, and from natural radiation from your granite kitchen top.

I didn't know that.  I run a clear MV in my bedroom.  I was always afraid that I'd be harming my eyes (or my skin) by being too close to it.  Thanks for the knowledge!

@ DimBulb-- I remember people saying that you shouldn't turn fluorescent lights on and off within 20 minutes of each other because you'd use too much electricity & that you'd waste power by doing so!  In that case, it would be bad for me, because I love to switch preheat lights on and off and off and on etc!

Thanks for the info. I wonder why all that propaganda was aimed at Cool White? It sure seemed like alot of other color temps started flooding the market after these reports. Before, it rare to see anything but Cool White.

Brian, when I was a kid, my parents always told me the same thing about switching lights on & off but I thought they just didn't want me to play with the light switches!
With fluorescents, I'm more worried about shortening their lifespan.

At my work the garage lights are preheat with starters, controlled by a PIR switch that turns them on for 15 minutes. Lamps last generally a little less than if they are on constantly, but not much, they easily make 3 years. The starters do however fail more often, I generally change these with the tubes, other lamps I only do this if the lamp has been dead for a while and the starter is stuck closed. The last ones I did this week friday, one starter was stuck, other was ok. The tubes still have life in them, but I put the new Philips daylight in to remove the last lifemax tubes.

I have a switch-start 2D fixture in the bathroom - which gets switched on and off about 6 - 8 times a day - the lamp lasted 8 years!
I had another 2D fixture in the kitchen which was switched on once per day and left on for 3-8 hours depending on time of year - the lamp lasted 4 years!

In this case the lamp with the frequent switching outlasted that which was left on for long periods.

it says that if you turn flourescents off-and-on many times you use more energy than you would if you left it on for a long peroid of time is this true?

Great, do any lamps of 4100K-ish color temperature count? If this is the case, WE'RE ALL GOING TO DIE! (especially me, as this is my favorite color temperature).

None of my SP41's installed 10 years ago have failed yet, on the other hand, my eyesight has declined rapidly over the years....

there is no danger of cool white normally. if exposed for long peridos of time there is. and i mean Looooooooong periods of time. most lights in my house are cool white. that ad just came out because of weird health- nut people in the 1980's

I'm pretty sure any UV hazards from properly operating HID/Fluorescent lights are significantly less than being outside on a clear day.  Theoretically if you've ever had sun burn, the damage is already done.

I'd worry more about applying sunscreen before going outside than cool white fluorescent lights.

@ DimBulb-- I remember people saying that you shouldn't turn fluorescent lights on and off within 20 minutes of each other because you'd use too much electricity & that you'd waste power by doing so!  In that case, it would be bad for me, because I love to switch preheat lights on and off and off and on etc!

The reasoning is rubbish. From pure electricity consumption, one start consume similar energy as half a second burn time...
The 20 minutes recommendation come from the lamp wear equivalent on preheat ballast.
For programmed-start CFL's (and some cheaper electronic ballasts), there is yet another reason - the preheat time is controlled by a PTC heat-up time, so it has to properly cool down before new start, otherwise the preheat time would be too short, so excessive wear on electrodes (no advantage from the programmed start feature). But this is a different topic.