Sunday, 13 September 2009

Mercury problem even worse than suspected

Chinese workers mercury poisoned!

As I mentioned out in my March post about mercury in CFLs, many CFLs made by leading manufacturers in China are produced in fully automated factories where no worker is exposed to mercury. But there are also many smaller manual factories, in which the phosphors and mercury are administered by hand. The Times Online article 'Green' lightbulbs poison workers confirms this information:
"In southern China, compact fluorescent lightbulbs destined for western consumers are being made in factories that range from high-tech multinational operations to sweat-shops, with widely varying standards of health and safety." [1]
As I pointed out, hand-dripping risks more mercury being injected into each CFL than the specified limit. VITO, the consultant firm hired by the European Commission to do the preparatory study before the ban, found this procedure to be the likely explanation for the widely varying mercury content in sampled CFLs:
"VITO performed a control on the mercury content of a limited sample CFLi’s, currently available on the market. The control was made by atomic fluorescence spectrometry, conform CMA 2/I/B.3." (Sampe 1: 1.8mg; sample 2: 1.1mg; sample 3: 6.4mg; sample 4: 3.5mg, sample 5: 0.28mg.) "It must be stated that sample #3 significantly exceeded the maximum allowed mercury content. This is probably caused by the cheap but inaccurate method of mercury filling (drip filling) that seems to be very common in most small far eastern production plants." [2]
I also warned that this manual dripping will poison workers, as mercury vapourises at room temperature (+20 degrees Celsius). Now this is exactly what has happened!
"Large numbers of Chinese workers have been poisoned by mercury, which forms part of the compact fluorescent lightbulbs." [1]
Also, mercury mines in China are being reopened to meet the increased Western demand for CFLs!
"A surge in foreign demand, set off by a European Union directive making these bulbs compulsory within three years, has also led to the reopening of mercury mines that have ruined the environment." [1]
1. 'Green' lightbulbs poison workers
2. Domestic Lighting, Part 1, Chapter 4

Mercury contamination of your home

As if this is not bad enough, it appears that a broken CFL at home is actually more cause for worry than previously thought.

After the now infamous (and cited ad nauseam) accident in Maine, the Maine DEP had its own science team test how much mercury is actually left in a room after breaking a CFL on floors with and without carpets, which resulted in revised cleanup recommendations:

Revised Cleanup Guidance
Maine Compact Fluorescent Lamp Breakage Study (the original report)
Mercury in CFLs - special investigation (long and scary reading, including summary of the Maine Report + interviews & addintional info collected by Invesitate Magazine TV, New Zeeland)
New Electric Politics: The mercury issue (shorter summary of the summary)

Some quotes from the Investigate Magazine summary [with my emphases]:
"First off, the often-cited claim that bulbs contain only 5mg of mercury was clarified: it's an average. (..) The average amount of mercury in a CFL is 5 mg with a range of 0.9 to 18 mg. Obviously, the smaller (in watts) the bulb, the less mercury. Higher power (brighter) bulbs generally have more, although there can be fluctuations between brands as well."

"'Mercury concentration in the study room air often exceeds the Maine Ambient Air Guideline (MAAG) of 300 nanograms per cubic meter (ng/m3) for some period of time, with short excursions over 25,000 ng/m3, sometimes over 50,000 ng/m3, and possibly over 100,000 ng/m3 from the breakage of a single compact fluorescent lamp,' the report confirms.

"That's up to 300 times higher than the recommended safe level of inhalable mercury vapour. From just one light bulb. According to the DEP scientific study, while the 300 ng/m3 limit is the maximum allowable daily dose of mercury for the sake of legislation, there is in fact
no known safe level for mercury exposure."

"To put the exposure in perspective, a study of workers who had been exposed on a regular basis to 33,000 nanograms/m3 of mercury (roughly a third of the 100,000 ng/m3 peak caused by a broken bulb), and compared in a neurological test to a control group of 70 unexposed people, found they scored worse on 'mental arithmetic, 2-digit search, switching attention, visual choice reaction time and finger tapping'."

"'Sensitive populations are of particular concern with mercury exposures for a number of reasons.' 'Elderly and unhealthy individuals may already be at comprised health and be more susceptible to mercury effects than a healthy individual. For example, mercury does kidney damage which could exacerbate an already existing kidney disease'."

"'Infants and toddlers have much more vulnerable brains.' 'Mercury exposures have serious impacts on fetal and infant brain development. Elemental mercury can cross the placenta from a mother to fetus.' 'It is well established that the developing organism may be much more sensitive than the adult to neurotoxic agents,' reports Maine's DEP study. 'For example,
methylmercury exposure can produce devastating effects in the fetus, including cerebral palsy, blindness, deafness, and even death, while producing no or minimal effects in the mother'."

"The report also noted that
following official clean-up guidelines was still not good enough to eliminate the pollution. 'Although following the pre-study cleanup guidance produces visibly clean flooring surfaces for both wood and carpets (shag and short nap), all types of flooring surfaces tested can retain mercury sources even when visibly clean. Flooring surfaces, once visibly clean, can emit mercury immediately at the source that can be greater than 50,000 ng/m3. Flooring surfaces that still contain mercury sources emit more mercury when agitated than when not agitated. This mercury source in the carpeting has particular significance for children rolling around on a floor, babies crawling, or non mobile infants placed on the floor'."

"[T]he scientists note that the mercury contamination was considerably worse – nearly double in fact – at summertime temperatures (32C) than winter (23C)."

"Additionally (and this is why carpets have to be destroyed), the scientific team repeatedly vacuumed carpets where bulbs had broken, to see if vacuuming did eliminate the residue. They found that even after several attempts, the mercury was still trapped in the carpet fibres. To make matters worse, some of the vacuum cleaners were so contaminated that cleaning them was impossible, meaning not only was the carpet over and out, so was the vacuum cleaner."

"'If clothing or bedding materials come in direct contact with broken glass or mercury-containing powder from inside the bulb that may stick to the fabric, the clothing or bedding should be thrown away,' warns the US EPA."
"Maine state government is now officially recommends (...) that 'homeowners consider not utilizing fluorescent lamps in situations where they could easily be broken, in bedrooms used by infants, small children or pregnant women, or over carpets in rooms frequented by infants, small children or pregnant women.'

"Then there's the problem of what to do with the toxic waste. Surprisingly, plastic jars, like large peanut butter containers with screw top lids were little better than plastic bags, also failing to prevent mercury vapour from leaking into the house. The best method of containing bulb waste is inside a glass jar with a hermetically sealed lid."

"Brandy Bridges: 'They're not as eco-friendly as we'd like to think. Just the fact that they're being shipped in trucks and who knows how many cases get dropped? You're in your local hardware store, and they're broken on the floor, and you're walking by unknowing that there's mercury there, that people are just walking by and breathing in, and a lot of people don't have a clue'."

"Perhaps the most dangerous aspect to the CFL mercury issue, however, is not the instant 'spike' exposure caused by a breakage, but the effect of a string of breakages over the years on the toxicity of suburban homes. Picture a low income family (...) forced to use CFLs because of the light bulb ban and because they cannot afford even more expensive halogens. Picture a breakage, then try and estimate the odds of a stressed out (or drugged up) householder following proper clean-up and disposal procedures.

"Then picture a few more breakages over the years, none of them dealt with properly. Then try and figure out how much mercury might accumulate in the carpets, floorboards and walls of such a house over a 20 year span. Then try and figure out the impact such poisoning might have on every family that moves through that house, and how many taxpayer dollars might be wasted dealing with the health or crime problems that erupt downstream because of mercury exposure.

"When you buy a house or move into a rental, you won't know whether the home you're moving into is contaminated by mercury, unless you go to the extreme expense of getting it tested. Your safety, and your family's safety, will rely on the ability and willingness of other ordinary [citizens] to properly dispose of mercury laden light bulbs, and you'll never really know. The real cost is not one light bulb breakage, but how badly affected homes will be after 20 years of amateur attempts to clean up one of the deadliest neurotoxins on the planet. A generation of children crawling on mercury-infested carpets would give new meaning to the phrase, "dumbed-down".

"On the strength of these scenarios alone, there's a good case for actually banning the use of CFLs in homes, outright and immediately."

I couldn't agree more. And I don't see how any responsible politician or environmental organisation could either, after getting this new information.

Mercury & coal

For those who still believe that incandescent bulbs "cause more mercury emissions via coal plants", please understand that it is nothing but a cheap PR trick which seems to originate from the pro-CFL/anti-lightbulb lobby organisation IAEEL 1993, and based alternately on:

1. U.S. conditions in which, at that time, 59% of electricity production came from coal. [1] June 2008 it was 48,5% and decreasing. [2]

2. A Danish 'study' (= calculation excercise) from 1991 [3] in which a 60W (730 lm) 1000h incandescent (GLS) was compared with a 15W (900 lm) 8000h CFL, the latter assumed to contain 0.69 mg mercury, while electricity production from coal was assumed at 95%, as was the case in Denmark at that time - the highest in Europe! [4]. Based on these assumptions, CFLs were estimated to emit 1.69 mg mercury per million lumen-hour during production, operation and crapping phase, and incandescents 4.86 mg. However, these figures were seriously flawed then, and are even more so today:

a. "0.69 mg mercury" in CFLs is seems like a random fantasy figure, especially back in 1991! In 1993, IAEEL estimated CFLs to contain an average of 5 mg. [1] Eu consultants VITO consider 4 mg to be a realistic average now. [5] (Both are extremely pro-CFL and are not likely to exaggerate.)

b. According to EuroStat, the EU share of coal used in electricity production was 39% in 1991 and has since decreased to 29% in 2006 (though varying widely between different countries). [6]

Correcting for a and b (while still assuming the 15W CFL to give as much light as a 60W GLS and lasting 8 times longer) we get:

- GLS operation phase: 4.86 mg - 66% = 1.65 mg (as long as EU permits unfiltered coal emissions) = total 1.65 mg Hg on average. (In countries that don't use fossil fuels for electricity production, like Luxembourg, Iceland, Norway, Sweden & Switzerland, the sum total is 0.)

- CFL operation phase: 1 mg - 66% = 0.34 mg + scrapping phase (assuming no recycling): 4 mg = total 4.34 mg Hg.

In other words, when feeding correct numbers into the calculation, we get the opposite result!

See also my recently updated post Life Cycle Assessment for more LCA studies and details. And my previous posts about Mercury and Recycling.

1. Mercury: A Broader Perspective, IAEEL Newsletter 3/93
2. EIA: Electric Power Monthly, September 2009
3. Life Cycle Analysis of Integral Compact Fluorescent Lamps, 1991
4. More on mercury, IAEEL Newsletter 1/94
5. Domestic Lighting, Part 1, Chapter 4
6. Eurostat: Panorama of Energy 2007


  1. Yes, CFL mercury is a much bigger problem compared to power station mercury release

    Of course this is not unrecognized,
    particularly in a practically emission-free country like Sweden.

    But then the talk is of "solidarity"
    with Germany etc, ignoring that Germans can and will deal directly to lower the emissions anyway
    in line with overall EU mercury policy
    (which is basically "let's get rid of all mercury.. except in CFLs"!)

    Interesting about the mercury drip filling as reported by VITO - that organisation being what the European Commission likes to refer to
    when it suits them,
    and being behind the current research for the Commission:

    Finally, there is a lot more attention post-EU ban to the mercury situation, also in the USA.

    Unfortunately, often with "ban when LEDs are ready", "buy LEDs instead" recommendations:
    but it should be remembered that the ban is wrong in itself for many other reasons

  2. Right.

    The only lamps for which a ban would make sense, would be the high pressure mercury street lamp + CFLs for private use.

  3. This is assuming all CFLs are broken and their mercury content dumped into the environment... I'd be interested to see what the ratio of returned-for-recycling-unbroken vs thrown-in-the-bin-or-broken CFLs is.

  4. Recycling rates vary between countries. Some countries have efficient recycling schemes, others have none. For EU, I've posted the available statistics in an earlier post:

  5. Read the other posts about mercury and health effects and decide for yourself if you need to switch to a safer incandescent lamp type.

    An online electrician course (which seems very much like spam) is not likely to give you health information.

    LEDs may not be as safe as previously assumed.