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Questions Arising On Mercury In Compact Fluorescents
Patchw0rk F0g sends in an article from MSNBC on how some environmentalists are having second thoughts on compact fluorescent bulbs. Their relative energy efficiency is unquestioned. The problem is the mercury — enough in one bulb to contaminate 1,000 gallons of water, even in newer low-mercury bulbs. The EPA has an 11-step cleanup process to follow when you break a CFL in your home. The specialized recycling facilities that are needed are thin on the ground — about one per county in California, one of seven states where it is illegal to dispose of CFLs in the general waste stream.
I only like CFLs because they lasted longer than incadescents.
Otherwise, they suck.
I really think LED will be the future of lighting in most situations. It's a long-lasting, mercury-free lightsource that can be targeted to any frequency. We are already seeing them used in Grow Light applications and other such things all the time. I think it will be a great day when we start seeing LED light installations just about everywhere we are using traditional lights today.
put the what in the where?
I prefer Flambe as apposed flamebait.
This was on the BBC some months ago.
They were relatively reassuring about the health implications:
Something to be aware of, but not hugely worrying.
I played with mercury as a child. We used to rub dimes on it, and push it around on a desk and i our hands. I had like 5 pounds of the stuff in a bottle, enough co contaminate the solar system if ne CFB contaminates 1000 gallons of water.
So I'll be dying soon, anybody want to buy a low slashdot ID?
Sheldon
Tag this post: getoffmylawn
is not requiring the stores that push CFL to set up a recycle system. Home Depot and Walmart are busy pushing cheap bulbs from GE/China. They claim that they will last 5-7 years. Half of mine have burned out within 3 years. I have 8 bulbs waiting to recycle. Worse, I saw a GE/Made in China bulb catch on fire. I now buy Phillips/made in mexico only bulbs, but it does not solve the problem of mercury recycle.
I prefer the "u" in honour as it seems to be missing these days.
I wish this story would go away. Mercury is released by burning coal for electricity, and the total amount released to the environment is much greater with conventional bulbs.
For one thing, some of us have light-induced migraines. Fluorescent-lights are often a contributing factor. Whether it's the light spectrum output, the AC frequency, or some placebo, whatever, in *my* case, fluorescent lights seem to be a *major* contributing factor. I'm all for efficiency, but this case, Incandescent light is one of the few things that I have a hard time letting go. I *need* incandescent light in order to make my living... Nary that, just to survive.
I, for one, am looking forward to the inevitable
Simple. Mercury in CFL < mercury which would be released to produce (incandescent - CFL) energy.
It takes a man to suffer ignorance and smile
Be yourself no matter what they say
There's a much more substantial danger with asbestos. cigarette smoke. CO from your furnace, or from your attached garage. Radon. Electricity from the wall socket. And lead paint. These things seriously injure or kill thousands per year.
And now you tell me that mercury from my breaking-lightbulbs spree will kill my family tree? Good God!
The amount of mercury in a modern lightbulb is thousands of times less than what is found in a mercury thermometer or a thermostat. And let's not even begin to discuss the amount of mercury within traditional fluorescent bulbs and the amalgam in some fillings.
There is no "I disagree" mod for a reason. Flamebait, Troll, and Overrated are not substitutes.
The article barely mentioned the real facts. The power production for regular light bulbs over the lifespan of a CFL generates 2-3x as much mercury as is in the CFL. They are just fine.
Now it is a bit of a problem right now finding a place that will recycle them. Ikea is doing it, and Walmart is thinking of rolling out recycling bins in their stores. But industry needs a lot more motivation to start taking these back. Ideally most municipal recycling programs would allow the bulbs to be placed in their bins (maybe in cardboard protectors or something. A decent article would have focused on this aspect of the story, and it was again just mentioned in passing.
Personally, I think the threat from mercury is a bunch of liberal hype. I'm not saying that it isn't dangerous, but let's wait until the science is all in before making this a political issue and conjuring all sorts of doomsday scenarios about "mercury in tuna" and such. Why is it that the media only covers the pro-"mercury is dangerous" side of the debate?
English is easier said than done.
But how much mercury leeches into the ground from a LED thrown into the landfill after it "burns out" (i.e. stops working for whatever reason) or how much mercury gets into the immediate environment when they break? If you can come up with soft white LEDs than aren't too much more expensive than CFLs then I, at least, will buy them.
Really, you can do all the efficiency comparisons in the world, all I give a crap about is if they're cheaper to put in my lamps and fixtures than incandescents. If they're about the same as florescent, 99% of people are going to shrug and buy that which isn't going to give their children brain damage when they break.
Honestly, this is my biggest problem with the environmental movement in the US today, it's never satisfied with even the slightest amount of progress. Fossil fuels are unacceptable because they pollute, but so is wind power because it interferes with migration paths. Incandescent bulbs are inefficient but we can't use CFL's because they contain mercury. We want the fuel efficiency that diesel engines already offer but we can't buy them in the US because of sulfur emission regulation. Everything has trade-offs. Sometimes you just have to pick the lesser of the two evils and go with it.
If you are in an office or school, look overhead and determine what type of lighting you have. There are a lot of places where it is fluorescent lighting in the long tube format.
Said tubes also contain mercury. But few, if any people, seem to consider these as part of the mercury contamination controversy.
If these tubes aren't a problem because they are disposed of properly, couldn't the CFLs be put into the same disposal chain?
And if the tubes ARE a problem because of improper disposal, shouldn't they also be mentioned along with the CFLs?
That's news to me. I'm sure it is but you can't just write a law like that and then put it on display in a locked cabinet in some basement somewhere with a broken sewer line. You actually have to advertise it. The funny thing is I have a broken CFL in my house right now. I have it because my wife accidentally knocked it off the shelf and the packaging while shear resistant doesn't pad the bulbs at all so it broke. Since she broke it, she bought it. So now how exactly am I supposed to deal with that?! I doubt even the hazerdous waste place will take a broken bulb.
Probably as soon as someone can mass produce an LED lightbulb that is affordable, long lasting, and produces natural looking light in large quantities. As of right now LED's are generally efficient and long lasting, but have an unnatural blue hue to them which turns a lot of people off. A lot of people realize that LED's are the future, the future just isn't here yet.
It's not elemental mercury that does damage, but mercury that has been included into organic molecules by other organisms that you eat, such as fish (which in turn ate smaller animals with mercury and so concentrated the environmental mercury for your inconvenience). There was a lot of talk about the evils of mercury fillings but of all the millions of people who have them, practically none of them has ever had mercury poisoning as a result - but what is the cancer risk from having epoxy resin slowly degrading in your mouth?
There is an awful lot of FUD around the dangers of mercury and other heavy metals.
And just to demonstrate, I shall now drink this cup of mercury whilst reciting the first chapter of Alice in Wonderland backwards.
Do it yourself, because no one else will do it yourself. [beta blockade 10-17 Feb]
... is that the percentage of mercury in a CFL bulb is likely NEVER to make it into the water table unless they pump from the very very bottom of the water table/tank. Mercury is so heavy it automatically sinkss to the bottom of whatever is storing it with water. Memphis Light, Gas, and Water (mlgw.com) has noted this in their water treatment plants for YEARS when concern about their aquifers and mercury hit the news. It's a non-issue for the most part unless the water pumps hit so far at the bottom that they suck up mercury. This is why Memphis has some of the best aquifer water there is on the planet.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
, they will STILL reduce the overall mercury emission into the environment over their lifetime, compared to equivalent incandescent bulbs.
Mercury (and uranium!) is present in the smokestack emissions from coal-burning powerplants. By reducing the amount of electricity used, CFLs actually reduce overall mercury emissions. And since the mercury they do contain is in a sealed glass tube (as opposed to being spewed into the atmosphere and settling out onto the ground), their toxic content is easily managed through recycling efforts.
Remember "News for Nerds, Stuff that Matters"? Help make it a reality again! http://soylentnews.org
Does everything on /. always need to be a political debate?
"mercury in tuna" and such. Why is it that the media only covers the pro-"mercury is dangerous" side of the debate?As opposed to the "mercury is safe" side? The bottom line is that while safe levels of mercury are still up for debate (though nearly all of the research indicate save level in terms of g/m3), we know that it is harmful, bioaccumulates (there's the fish problem), and is something that, like lead, should be kept out of commercial products as much as possible.
500kg of mercury is less than 10 gallons and that's the same as 100,000,000 CF bulbs.
If you eat 11oz of Yellowfin each week, you'll consume the same amount of mercury as eating 1 CF lightbulb each year, or 4oz of swordfish each week.
Ladies and gentlemen, a bit of math.
Amount of mercury in 1 CFL light bulb: 5 milligrams (source: TFA)
Amount of energy saved by using a CFL bulb instead of incandescent, over the lifetime of the CFL:
10,000 hours * 75 watts * 75% energy savings = 0.6 megawatt-hours
(http://en.wikipedia.org/wiki/Compact_fluorescent_lamp#Lifespan)
Fraction of that energy that would be generated by coal-fired power plants: about 50%.
(http://www.eia.doe.gov/cneaf/electricity/epa/epat1p1.html)
Coal power plant energy savings: 0.3 megawatt-hours
Annual emission of mercury by US coal-fired power plants: 48 tons/year in 1999
(http://www.nescaum.org/documents/rpt031104mercury.pdf)
Power output of US coal-fired power plants: 1,900,000 gigawatt-hours in 1999 (about the same today)
Mercury emitted by coal plants: 48 tons / 19000000 GWh = 23 milligrams per megawatt-hour
Power-plant mercury emissions avoided by using a CFL bulb over its lifetime:
7 milligrams
So it's a wash. The amount of mercury in the bulb is roughly the same as what would be emitted by a coal-burning power plant, if you stuck with incandescent bulbs.
But the mercury in a CFL bulb is a lot easier to clean up than the stuff spewed into the atmosphere by power plants.
No problem; they'll just do what the printer ink cartridge manufacturers do: Build in a chip that commits suicide after some specified period of time. That could be in hours of operation, or even calendar time. In the latter case, you're virtually renting them.
First, I will overlook the nonsense about GW.
:) ).
Second, why to use CFL? BECAUSE of mercury. The vast majority of power plants in the world ARE coal plants. If you burn the CFL for an average 1 year period AND you break the bulb outside of your house, you will still have introduced less mercury into the atmosphere than had you used the best incandescent over that time. Why? Because even Western American coal has a lot of mercury, and that is considered some of the cleanest coal in the world. Burn Eastern American or worst of all, most seams in Chinese coal and the mercury content is ENORMOUS. So, if you want to lower the total mercury in the air and environment, then use the CFL. If you are concerned about a mercury bulb breaking in your home, do not use them in places prone to breakage. For example, do not put it in a lamp that can be tipped. Likewise, do not use them around the mirrors in the bathroom or the garages. AND most of ALL, do not put them in the kids rooms. If there is a breakage, you must ventilate the house for a while AFTER the clean-up.
If you are still concerned about the mercury in your home AND want to lower your OVERALL energy bill, then get some LED lights. They will pay for themselves over a 1-2 year period, though hard to believe with a $1/watt bulb. Of course, like CFL, the light takes getting use to. I wanted to replace some halogen hockey pucks (10 watts each) in our kitchen with led pucks (2.5 watt), and the wife said not a chance after seeing it in action. Funny thing is that the leds was actually brighter. But, happy wife, happy life (of course, that statement ignores sociopathic ex's
Electricity is fungible. If you use 1 kWh less of your local hydro power, then that 1 kWh will be transmitted to some place where they tend to use coal-fired plants. For instance, in the US, the Pacific DC Intertie (http://en.wikipedia.org/wiki/Pacific_DC_Intertie) carries hydro power from Oregon all the way south to LA; and LA gets half of its power from coal. If not for that long-distance DC link, it would be using a lot more coal power.
You could make the same argument about low-flow showerheads or toilets or plumbing fixtures in general (how long to those last).
People still remodel, new houses are built, old houses are destroyed, people break them, someone will come up with a new lighting mechanism (maybe that aluminum foil micro plasma lighting will become popular), and people will go through another replacement cycle.
This particular topic has been discussed at least once as an article on slashdot, and almost every energy related topic ultimately wanders onto mercury in fluorescent light bulbs.
However, here's the abbreviated facts (and I apologize I'm not going to go look up all the numbers again, but if you don't take my word for it, you can look the numbers up yourself):
A typical compact fluorescent light bulb has about 5 mg of mercury in it. All NEMA manufacturers voluntarily agreed to this a maximum. This is roughly as much as is contained in 50 cans of tuna. The FDA recommends consumers limit their intake of tuna to 1 serving per week, so that's about the same as a year's supply of tuna. So is this enough to be a health hazard? Not really.
First of all, the tuna contains the compound methylmercury, which is formed by bacterial action and bioaccumulates much more readily than elemental mercury. A greater portion of the latter passes through the body unretained. Secondly, you eat the tuna. Nobody eats a light bulb. Not to mention, the FDA recommendation is conservative, except in the case of children and pregnant women.
Generally, the lightbulbs don't get broken until disposal, and therefore completely contain the mercury, but if it does, it can safely be disposed of in the garbage. The EPA recommends that you not touch the pieces with your bare hands, so use a broom and put it in a bag. Most of that tiny amount of mercury is actually condensed on the phosphor that lines the bulb, and therefore fairly effectively immobilized, although it will slowly evaporate.
Is it an environmental hazard? Again, not really.
The EPA has calculated, based on the US's current power source mix, that the mercury contained in a CFL is more than offset by the power savings, which reduce the amount of mercury released into the atmosphere by burning coal. Additionally, don't forget that the mercury is trapped inside the bulb until broken. Even then it's at best a small concern. Most of the mercury in the environment is naturally occuring, although in specific areas industrial pollution has resulted in significantly elevated mercury levels.
Additionally, due precisely to disposal concerns, many CFL retailers have implemented recycling programs so you can drop off you dead CFL's and they will dispose of them properly. Not only that, but non-commercial users are actually allowed to dispose of fluorescent bulbs in the trash in most cities. Sound bad? The average US citizen produces about 4 pounds of landfill waste per day. Mix in half a dozen CFL's per year with the trash of an average household, and the amount of mercury ends up being about the same as natural occurs in the earth's crust.
Again, you don't have to believe me, but if you search around for the relevant information (natural abundance of mercury, trash produced per capita, USDA recommended limits on tuna intake, EPA datasheets on mercury and methylmercury, etc) you can verify everything I just wrote.
People will probably complain that a lot of those LED's have circuits that cause them to blink. Any LED with a dimmer blinks.
I called the phone number to get a replacement bulb for one that burned out about two months ago and they mailed me a new one. When I got it it was broken in the shipping box and when I called the number for a replacement one I said I would prefer not to get the broken one out to read the numbers because I know they contain mercury. The customer service rep told me the mercury was contained within the base of the bulb and I was at no risk even if the bulb was broken.
I was skeptical and did not handle the bulb. Thoughts?
One thing that should be remembered about the current regulations for mercury are very strict in contrast to the levels associated with deterministic effects. This is perfectly natural since the natural occurrence of mercury is in such low concentrations. In fact almost all practical problems with mercury and how to deal with it are somehow linked to the inability to accurately measure it at the concentrations it begins to harm organisms.
Second, the speciation (division between different compounds) of mercury makes a huge difference in how the body absorbs it. The elemental form, found in old thermometers, switches and these CFL's, is practically biologically unavailable when liquid. There was a man in Taiwan who drank, IIRC, around a kilo without permanent effects. Oxidized mercury (HgCl2, Hg(NO3)2, and a few others) are also generally quite unavailable--several were used as syphilis medicine for quite some time--but led to a number of occupational hazards and poisonings. Mercury sulphide, on the other hand, is so unavailable that it's considered a "retirement path" in the mercury cycle. Among the variety of questionable Chinese medicine are "herbal balls," which have been found to contain up to 1.2 g (over a hundred CFL bulbs worth of mercury) of HgS. Finally, there are organic mercury compounds which are extremely toxic, but these are irrelevant except when they are produced by man in large quantities (though not necessarily on purpose) or when large amounts of inorganic mercury are available to anaerobic bacteria.
Almost all large-scale mercury poisoning has been due to the organic form entering the food supply.
However, though elemental, the form found in CFL's would most likely be vaporized if it got loose in your home. Vaporized elemental mercury is readily absorbed into the lungs, and can cross the blood-brain barrier, leading to temporary neurological effects in the few well-studied cases of household aspiration of the elemental form. Irritability and hyperactivity are typical symptoms.
Five milligrams is a good round number for the Hg content of a single CFL bulb. What is that for a person? 0.1 ppm? Well, the onset of symptoms in the victims of the Minamata disease (organic mercury poisoning) was a hair concentration of around 50 - 125 ppm (as mentioned, the margin of error on everything related to mercury is HUGE). Ca 100 ppm blood concentrations were found in the mothers of newborns in Iraq after an incident there with fungicide-laced grain in the 1970's. Again, uncertainty is the rule, and due to widely-varying affinities for heavy metals between different organs, there's very little one can predict in a given incident.
On a side note, while doing my thesis on a power plant mercury control system, I found my first grey hairs.
Many countries, including the US and China have decreed an end to incandescent bulbs. The number of compact fluorescents are about to hugely increase in number. Yes, the amount of mercury per bulb is small but when they're the only bulbs available to billions of people that small amount will become significant. Without a good recycling system this will become a greater environmental issue.
I'm sure urban environments will do fine with recycling. I wouldn't want to bet on that in rural China if I got my water from local wells. Or rural Mississippi for that matter.
The latest energy bill signed by President Bush requires the phase out of incandescents to either begin or be complete ( I don't recall which) by 2012.
According to industry information, standard flourescent tubes like the 40W T12 in your office ceiling contain 2-6 times more mercury than a compact fluorescent. Bulbs like these have been in use for almost 70 years, and there are now literally billions of tubes in use worldwide without any published evidence of widespread mercury poisioning from them (most of the environmental rise in mercury, such as affected the Japanese fishing industry, is from commercial chemical proccessing and power plants). If this type of article raises awarness of mercury problems and leads to a recycling program as comprehensive as that for lead in car batteries, then it is a useful thing. If this article is another industry subsidized lobbyist attempt to smear 'environmentalists', then it is not helpful to the public debate at all. Unfortunately it is probably the later, since it chooses to cite the non-news incident of Ms. Bridges, which was first widely reported by the conservative pundits (NOT real news media) about a year ago.
Back in the long ago, streetlamps were powered by gas. Every evening, a person called a lamplighter would come and light the streetlight. (The bars sticking sideways out of lampposts were not decorative. They were there so a lamplighter could lean his ladder against them so he could climb the pole.) Every morning he would go around and extinguish the streetlights.
Gas lights did not use an open flame for lighting (well, they did, but not for long). They used a special cloth "wick" called a mantle. This mantle glowed brightly when heated by the gas flame. Over time, the mantles would disintegrate, and new ones would have to be installed.
Now there were two once vibrant sectors of the lighting industry that have been virtually eliminated by progress. Sure, a few thousand people lost jobs. There were better, cheaper, safer alternatives, so people used them. The same thing will happen with the incandescent bulb makers, and the fluorescent bulb makers. LEDs are a better, cheaper, safer alternative. A few thousand people will be put out of work, and once vibrant sectors of the lighting industry will fade away. Sure, a few companies will hang on, doing specialty work, but count on GE, Sylvania, Philips, and their ilk closing a lot of bulb factories in the future.
When our name is on the back of your car, we're behind you all the way!
LEDs, one way to make them is with arsenic. Now one diode of arsenic is nothing, put billions in the dump, let the plastics rot a bit and...
You missed the point. LEDs DO NOT GO IN THE DUMP AT ALL, because they pretty much 'never' burn out.
paintball
If you eat 11oz of Yellowfin each week, you'll consume the same amount of mercury as eating 1 CF lightbulb each year, or 4oz of swordfish each week. ...You've apparently never tried to light a room with swordfish.
paintball
There will always be a replacement market for bulbs... new construction, accidental breakage, weather exposure, etc... If there is demand, there always be a supplier. If the price is too high, then we have the situation we are in now and people will continue to use other technology.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
> A lens can diffuse the beam, and they currently exist in red, green, and blue forms that could
> be combined into the proper color temperature.
That won't work. There is a good reason white LEDs aren't just tri-color LEDs without seperate leads. See the slashdot story from this weekend about the artist exploiting the monochromatic light of LEDs to produce interesting effects when illuminating paintings. If you mix primary colors to get yellow paint, paint something with it and shine a yellow LED on it you see black. Oops! Guess that is why white LEDs use a deep blue or UV LED with a fluorescent coating inside the package. A LASER diode would of course be an even more extremely monochromatic light source than a normal LED, plus the unexpected problems of illuminating ordinary scenes with coherent light.
Democrat delenda est
The LED industry is doing quite well at the moment. I've never had an LED fail yet, but I keep buying new devices with LEDs in them. In future, I wouldn't be surprised if it becomes normal for lamps come with LEDs built in, which you replace by replacing the entire lamp - if they last a decade or two then your taste in light fittings will probably change before the LEDs burn out. There might be a bubble as everyone converts to LEDs, but gradually production will settle down around replacement rate.
I am TheRaven on Soylent News
I found an EPA document from September 2002 (linked below) saying that during a 5 year span, a lamp running a CFL which is then thrown in the trash will release less mercury overall into the environment than a lamp running incandescent bulbs for the same time span. This is because the power required to run the incandescent bulbs has the coal power plant outputting a lot more mercury.
Does anyone know if the EPA still says this, or if the number are still believed to be true? If so, wouldn't that destroy this entire article? Unless of course you're worried about 5-ish year's worth of mercury being concentrated in one location. But, the article cites the waste stream, ground water, air, and landfills as the problem location, as well as localized breakage.
The fact sheet can be found at http://www.arlingtonva.us/Departments/Topics/Documents/9662MercuryCFL.pdf
The problem is the mercury -- enough in one bulb to contaminate 1,000 gallons of water, even in newer low-mercury bulbs.
The number on another scaremongering article was 6,000.
Either way...
There's a gaping flaw in the logic that if you count PPM for a safe dose, look at the volume, then multiply up. It assumes the mercury is even close to equally disolved in that water.
If a drop, the volume of which is found in a typical CFL, dropped in to a thousand gallons of water and sank to the bottom, whilst I wouldn't happily do so, I'd still be willing to drink a glass from off to the side of where that drop went in. A little more nervously, I'd still be willing to do so a few weeks later, assuming the drop was still largely intact at the bottom.
On the flip side, let that drop sink in to a million gallons of water, thus apparently a thousand times under the "safe dose"... and I challenge anyone to be willing to drink the cupfull taken from where the drop sank, original drop included.
Yes, mercury is bad for you. It turns you in to a character in Alice In Wonderland.
On the other hand, we're druming up fear by pointing to a perfect distribution and the safe level (accepting that safe levels are usually many times lower than the point at which harm is a likelihood that's why they're called "safe" not "minimal risk" levels).
If you're going to get your panties in a bunch about that, you'd better not each fish (particularly swordfish, shark, smallmouth bass and pickerel). With an FDA "safe for human consumption" of 1ppm, shark ranged 0.30-3.53ppm in samples tested, averaging 0.88ppm and swordfish at 0.36-1.68ppm, averaging at 0.88 (FDA).
By comparison, the mercury maybe getting out of a bulb, disolved properly in to ground water, getting in to the water supply and failing to get filtered past the safe level is somewhat less of a risk than the statistical variance that means you'll almost certainly clear the safe levels in at least one case if you have a nice swordfish steak half a dozen times at your favorite restaurant.
Neither is likely to do you much harm. In both cases, getting in to your car and driving to work is a vastly greater risk, yet it puts the silliness of the debate in context when simply eating fish is far worse for you (on that one very limited axis).
If your electricity comes from coal, the power saved by a CFB prevents a greater amount of heavy metals (including mercury) from being dumped into the air, water and ground downwind of the coal plant. I like eating fish, how about you? This argument won me over, I hope it was not a lie designed to sell me a bunch of expensive light bulbs.
The service life of CFBs and regular bulbs makes me suspicious. CFBs do not last much longer than incandescent bulbs used to. I've had 2 of 12 burn out over a year or so despite the 5 year promise on the box. Incandescent bulbs used to be that good and halogen incandescent bulbs still last longer than CFBs. Ask yourself when the last time you changed your car headlights was.
Friends don't help friends install M$ junk.
The amounc of mercury in CF's is indeed a VERY SMALL AMOUNT compared to what I've personally SEEN, and heard about others being exposed to:
When I was a child at the pediatrician's examining room (40+ years ago) they used blood pressure meters (whatever they were called) that used MERCURY in them, much like a thermometer. The mercury went up and down in a vertical glass tube driven by air pressure in the arm cuff, indicating blood pressure. I saw one that was BROKEN with the mercury pooling in the bottom of the case. The doctor saw it was broken and removed it from the room, and came back with another of the same model that wasn't broken, and of course measured my blood pressure with it.
In a high school science class there was a plastic squirt-bottle of mercury, and a girl had put a drop into the palm of her hand and was playing with it, pushing it around with a finger. The teacher came in and saw what she was doing, and he calmly but firmly told her "When you're through playing with that, carefully put it all back into the bottle, and before you eat lunch, be sure to was your hands very, very thoroughly." I was rather interested in playing with it myself, but after hearing the teacher say that, it reminded me that mercury was Not Safe, that a very small amount ingested could kill (MUCH less than what that girl held in her hand!) and I lost any interest in touching it. Thinking about it now, I'd be surprised if there is ANY such mercury in high school science classes or labs thesedays that isn't left over and long-forgotten from decades ago.
As an adult an aquaintance told about remodeling old houses and taking the mercury out of old nechanican thermostats (they used mercury in a glass tube that tilted one way would connect two wires stuck into the tube, turning on the heating system. The tube was mounted on a spiral of bimetallic metal, which would change the tilt with temperature). He told of putting the mercury into a jug, that they had collected the mercury from dozens of those things, then someone stole the jug (one can only hope the thief disposed of it properly).
Mercury is indeed dangerous to human health, and it's good to know that "CF's have such-ahd-such amount of mercury in them." As I've grown older, optimizing my health and safety have become more important to me (I don't drive drunk, because, well I don't drink - I quit smoking 16 years ago, always wear my seat belt, eat healthier, get some exercise, etc) but the amount in CF bulbs is not a particular worry for me, and doesn't stop me from buying and using them out of fear that one might break with me in the room.
Tag lost or not installed.
Even in the US 50% of electricity is generated with coal. Yes, it's bizarre that it is still so, but it's true.
In the rest of the world the situation is considerably worse. Where were your lamps made? I don't think the steel poles that streetlamps are made from come from an area where nuclear and hydro are the predominate source of electricity. It's highly doubtful that the lamps at your local hardware store are made in such a place.
And then there's the fact that smelting of steel isn't done with electricity. They pile the steel scraps into a huge chimney that's mostly full of coal, light it up and then force air in until the heat from the coal heats the steel enough to melt. A very carbon intensive process, this. This is the part the part that uses the most fossil fuels for almost anything made of steel, no matter how it spends the rest of its life.
Compared to these issues the energy burned by the bulb is probably a trivial fragment of the total carbon budget for a light. Every little bit helps though.
Some of the realities of carbon output are pretty scary. All tars exposed to an oxygen atmosphere are oxidizing (slowly burning). That means every square inch of asphalt between your house and your job are doing their bit to add to global warming, and contribute a considerable fraction compared to the fuel powered vehicles driving over it. The road burns whether you're driving over it or not, so all those huge vacant K-Mart parking lots add up to quite a lot.
Help stamp out iliturcy.
I agree with Twitter. Quote: "If your electricity comes from coal, the power saved by a CFB prevents a greater amount of heavy metals (including mercury) from being dumped into the air, water and ground downwind of the coal plant."
This is not the first time a Slashdot article has misled us about mercury in compact fluorescent light bulbs. See this comment from a year ago: Misleading article. Quote from the second link in that comment: "China is also the world's largest emitter of mercury..." China's coal-fired plants emit TONS of mercury, and the mercury travels everywhere.
Is someone at Slashdot paid to post these articles, to sell LED or other lights? Or is it just ignorance?
So called "white" LEDs are actually blue or violet LEDs that have a dab of phosphor on the chip. The phosphor eventually gets dimmer and dimmer, just like the pixels on a plasma TV screen, or the burn-in on a CRT screen. Even compact fluorescents exhibit this burn-in dimming over time, I had a number of the old U-shaped compact fluorescents with magnetic ballasts at one time, and they still worked but just weren't as bright as when new, so I changed them out for newer corkscrew fluorescents.
I have some white LEDs in a few projects I built when they first came out, and some are already turning bluish-pink as the phosphors fade.
Movies are filmed at 24fps (double flashed in theatres at 48Hz - but still just 24 frames/sec). This is generally not noticeable since the shutter speed is set during filming to blur each frame except in certain high-action scenes (Bourne comes to mind) where the producer wants the added anxiety produced by a high shutter speed, no blur, stark, high contrast scene.
NTSC is 60 half frames per second - a rate also considered the MINIMUM for a CRT monitor refresh rate. 60Hz CRT monitors gives me a headache. 60fps is not fast enough for certain things - for instance, watching downhill skiing. One half frame the skier is on the right half of the screen, the next, almost to the left side. For a split second it appears that there are 2 skiers, since the blob of darkness is not connected in the two frames, since the shutter speed is high and he is hurtling down the mountain at 150km/h. For this reason I am saddened that the HD spec didn't include a 120Hz rate, perhaps as a 720i 120Hz. Some TVs support 120Hz - though only through interpolation. I don't think there are any that accept 120Hz sources over HDMI, etc.
The 60Hz LCD refresh rate is different since, except for a very few "Gamer" LCDs, the screen does not go black between refreshes. In the Gamer LCDs, switching all the pixels off momentarily is supposed to reduce motion blur - I'm not sure how well this works since I have never seen it in person.
However all of those are steady state - head stationary, object stationary - rates.
When you get fast motion, and combine that with persistence of vision, things break down. Especially at night. Especially for red, bright red, on a field of darkness. Taillights. At 100Hz, you cannot see the LEDs blinking, but movies your head back and forth burns copies of the tail light into your retina, like mouse trails. Alternatively, if you are stationary on the side of the road, a passing car leaves a ramjet-esque punctuated string of red taillights in your vision. This is very distracting. If only one could rewire them to spell out words as you are driving by... Hmm...
I live in Saskatchewan, where we get down to -50 and below, sometimes, in the winter. I have CFL bulbs in my outdoor security lights (over the doors and so on), on a switch that automatically turns them on at dusk and off at dawn. When it gets really cold in the winter the outside lights sometimes take about ten or fifteen minutes to get going. They burn a sort of pale pink colour that doesn't really give any usable light until they get warmed up, but after the first fifteen minutes they provide almost as much light as they do in the summer.
If you're a zombie and you know it, bite your friend!