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Questions Arising On Mercury In Compact Fluorescents
Posted by
kdawson
on Thursday March 20, @06:31PM
from the now-they-tell-us dept.
from the now-they-tell-us dept.
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.
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Hardware: A Super-Efficient Light Bulb 466 comments
Chroniton writes with news of a Silicon Valley company, Luxim, that has developed a tiny, full-spectrum light bulb, based on a plasma of argon gas, that gives off as much light as a streetlight while using less power. The Tic Tac-sized bulb operates at temperatures up to 6000K and produces 140 lumens/watt, almost ten times as efficient as standard incandescent lamps, and twice the efficiency of high-end LEDs. The new bulbs also have a lifetime of 20,000 hours. There's no mention of mercury or other heavy metals, which pose a problem for compact fluorescents.
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LED lighting (Score:5, Insightful)
Re:LED lighting (Score:5, Insightful)
Re:LED lighting (Score:5, Insightful)
For me, I'd add in a cost justification as well. I'll do it when they reach a cost that justifies their purchase over a incandescent or CFL bulb.
LED house lights are a lot like electric cars...
They're just too expensive at the necessary light levels for a home. Flashlights, being both dimmer on average and portable w/limited power supplies are a different justification.
For the disposal thing, I'd say to allow them into recycling trash. At the very least, properly manufactured CFLs should drop the number of bulbs tossed in the trash by a factor of 10-20.
Re:LED lighting (Score:5, Informative)
like daylight. Not blue, not yellow. It has 36 LEDs dotted around it, so it isn't in the
classic bulb form.
This is a similar one (Chinese products; could be countless copies):
http://evilidler.webofcrafts.net/S660E27-36D.jpg [webofcrafts.net]
Re:LED lighting (Score:5, Insightful)
On the one hand, they're Extremely bright for the electricity consumed, very good, they can come in any wavelength of color, for multicolored lights like Christmas lights, or for 'party bulbs' that with a little circuitry could produce a flashing swirl of rainbow colored light by switching various LEDS off and on... They're very small, and that means you can make any variety of decorator bulb configurations...
On the other hand, they NEVER BURN OUT. the MTBF on a LED is 300,000+ hours http://www.iddaerospace.com/design_development/faq_transition_flight_deck.htm [iddaerospace.com]
that's over 1305% longer than Compact Fluorescent Bulbs... in truth a LED can easily last 500,000 hours of use, the MTBF is just an estimate.... and forget them burning out from being switched on and off, Myth busters tried to do it, they tested every array of lighting combinations, and the LED array was happily blinking away 3 months later, when they finally pulled the plug on trying to get them to burn out from switching them on and off...
So, now what do you do? The government assumes that by 2012 LEDs will use 1/3 the watts per lumen VS Compact fluorescent bulbs... so it's not going to take environmentalists long to promote the usage of LED lighting...
So LEDS are a double edged sword for the lighting industry, on the one hand they're the best of the best for the environment, but on the other hand there is no turnover of bulbs. you'll be giving the LED bulbs to your grandkids before they have to replace them... For instance if you use a light 3 hours a day it will last statistically nearly 274 years. if like wal-mart you run the bulb 24/7/365 the bulbs will last an average of 34.2 years. 34.2 years.... yeah you might forget how to change a light bulb, once you get used to LEDs.
Re:LED lighting (Score:5, Insightful)
Re:LED lighting (Score:5, Informative)
Re:LED's blink too! (Score:5, Informative)
No matter how much you whine, you cannot see that.
If you can, then your only deluding yourself that you can.
Re:LED lighting (Score:5, Insightful)
Re:LED lighting (Score:5, Insightful)
Depends on their proximity to my bedroom window.
Re:Programmed Obsolescence (Score:5, Interesting)
Additionally, a lot of people are looking at LEDs like regular lights. They are not. They can be flexible, shock resistant, and sealed tight. They are ideal for putting light in places where we've never been able to put bulbs before. In floors. In counters. In sinks. In walkways. In door frames. As desk surfaces. You can make your slightly raised door sills out of a low-brightness LED so that they are visible to people going through. These aren't things you will ever want to replace. While very energy efficient, I think that large-scale LED production will significantly change how we light things, and those changes will necessitate "bulbs" that never burn out.
Of course, there will still be LED "bulbs" shaped like light bulbs, which fit into a standard socket. And I'm sure that some brilliant company will do as you say, and program in death. But the strips of "TruSun Dimmable"(tm) LEDs you have installed around the perimeter of your room when you re-do the ceiling won't have this "feature". They will be there for your grandkids to see.
Re:LED lighting (Score:5, Informative)
http://www.superbrightleds.com/cgi-bin/store/commerce.cgi?product=MR16 [superbrightleds.com]
They have bulbs ranging in brightness from $8 to $50. I've seen this site before, but never tried out the bulbs. $50 seems a bit much, but I might go for one in the $20 range and see how it works in my desk lamp.
Re:LED lighting (Score:5, Funny)
Not New News (Score:5, Interesting)
This was on the BBC [bbc.co.uk] some months ago.
They were relatively reassuring about the health implications:
Something to be aware of, but not hugely worrying.
I'm dead (Score:5, Funny)
So I'll be dying soon, anybody want to buy a low slashdot ID?
Sheldon
Tag this post: getoffmylawn
Re:I'm dead (Score:5, Informative)
The powder in a CF "bulb" is the phosphor, which is toxic and hazardous in an entirely different way.
And, because basically the same stuff is in fluorescent bulbs and white LEDs, nobody wants to make a big deal out of it.
Oh, and injecting mercury is not that bad. Metallic mercury is not especially dangerous, especially because your body is already equipped to excrete a reasonable amount of it. Organic mercury compounds, on the other hand, are hideously unsafe and some of them are toxic in quantities as small as a spilled drop, largely because they have an easy time crossing cell walls.
Other home dangers! (Score:5, Insightful)
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.
I don't get it (Score:5, Funny)
Good grief (Score:5, Insightful)
Look overhead (Score:5, Interesting)
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?
Do the math (Score:5, Informative)
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.
An introduction to mercury (Score:5, Informative)
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.
Re:Three questions. (Score:5, Informative)
2. Mercury in filling is amalgamated with other metals and practically stable against leaching or vaporisation. Some studies have suggested you absorb more mercury by having old fillings drilled out than by leaving them in for a lifetime.
To put the whole problem with the CFB mercury in relation, 100 Million light bulbs at 5 mg each contain a total of 500 kg of mercury.
The EPA estimate for mercury emissions from coal fired power plants is 50,000 kg a year.
Further perspective (Score:5, Interesting)
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.
Re:MSNBC (Score:5, Informative)
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.