As I was suggesting at the end of part one, the harmonic distrotion effect is not the only problem with Compact Fluorescent bulb’s. Each bulb contains a small amount of mercury. Most of the environmental groups point to the fact that it is only a small amount of mercury and is not harmful whilst the bulb is intact. It is here that the issue becomes a potential problem. What about if the bulb breaks in your home? In this article Mercury in CFLs – special investigation by Ian Wishart, he reports:
We've all heard the marketing spin about so-called "energy-saver" light bulbs: they last seven times longer than an ordinary bulb, they use only a fifth of the (Real) power. In theory, compact fluorescent lights are the way of the future, a solution to soaring energy wastage and a sure-fire way to go green in the home and save cash doing it.
Sometimes what looks good on paper turns out to be not so flash in practice, and when politicians get involved it can be a recipe for disaster.
There are suspicions the light bulb policy may suffer the same limitations. Before you read any further, however, here's a figure to keep in mind:
"The energy saving potential is of the order of 6% of domestic sector electricity use, or 2% of total electricity use," top science consultant David Cogan has told the New Zealand government in a briefing paper. 1 Remember that figure: the banning of ordinary light bulbs will reduce total electricity demand by 2%. The question is, after you've read the full story,
whether you think…the … plan to save 2% is worth the effort.
THE MERCURY ISSUE:
Perhaps the most serious issue for householders arising out of next year's compulsory switch to predominantly CFLs is their mercury content. So far, the New Zealand Government has played this aspect very low key.
The Ministry for the Environment, found guilty last year of letting political appointees write its briefing papers instead of independent public servants, has posted this claim on its website:
"Energy saving lamps contain a small amount of mercury which makes them operate much more efficiently than incandescent and halogen lamps. Mercury is toxic to human health and bioaccumulates [Bioaccumulate – the accumulation of a substance, such as a toxic chemical, in various tissues of a living organism.] in the environment but the amount inside an individual lamp is not large enough to pose a hazard to users."
The spin is clear. The lamps are "energy saving", it is only a "small amount" of mercury, which makes the lights operate "much more efficiently". Importantly, on the safety side, the Ministry for the Environment assures New Zealanders that "the amount…is not large enough to pose a hazard to users". That is the official NZ Government position. Now let's examine the reality.
In March 2007, Brandy Bridges, a mother in the town of Prospect, Maine, in the US, heard the publicity about the new energy-saver light bulbs and went out and purchased two dozen of the CFLs for the family home.
While installing one in her young daughter's bedroom, Bridges accidentally broke the new CFL bulb, which shattered and fell to the carpet. Remembering that the bulbs contained a trace amount of mercury, she called around for advice, eventually hitting the Maine Department of Environmental Protection (DEP) who suggested she call in a hazardous waste crew.
…the Maine DEP called in its own science team to run some experiments on broken CFLs. The DEP team smashed dozens of bulbs in a series of tests to see just how much mercury they emitted, and how much was left in the environment after various clean-up scenarios were tried. The experiments were conducted over bare floors, and carpeted floors.
The study team reported back just a few months ago, in February 2008, and the findings in their massive 160 page report have stunned US safety authorities.
First off, the often-cited claim that bulbs contain only 5mg of mercury was clarified: it's an average.
"Without the mercury, the lamp would not produce visible light. 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.
One busted bulb in a bedroom produced very disturbing results in their tests.
"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.
…when Maine DEP scientists went back to Brandy Bridges' house some three months after the breakage, they found mercury contamination in the bedroom was still as high as 2000 ng/m3 – three months later and despite following all the cleanup recommendations.
In the end, the DEP ripped out her carpet and disposed of it as toxic waste. And little wonder. 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.
"The Maine Ambient Air Guideline (MAAG) of 300 ng/m3 is identical to the EPA reference concentration (RfC), which is designed to protect against chronic exposure. The RfC is based on a number of occupational studies, in which tremor, fine motor deficits, electroencephalography (EEG) and autonomic nervous system abnormalities, and cognitive deficits were observed. "A no-effect level (the level at which no adverse affects are observed) was not identified in these studies."
To make matters worse, scientists believe the 300 ng/m3 limit may not protect children or infants.
"Sensitive populations are of particular concern with mercury exposures for a number of reasons. Mercury exposures have serious impacts on foetal and infant brain development. Elemental mercury can cross the placenta from a mother to fetus.
For these reasons, acute peaks could be particularly problematic during pregnancy. Infants and toddlers have much more vulnerable brains.
"Neurotoxicants identified in adults may have different and more severe effects in developing organisms. Infants and toddlers also have a much higher rate of respiration than adults. Therefore they have a higher exposure to similar concentrations. They also are lower to the floor and therefore closer to the source of the exposure and presumably more apt to obtain a concentrated dose of mercury.
"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."
Additionally, pregnant women exposed to a broken CFL light bulb could literally destroy their baby, in the wrong circumstances:
"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, methyl mercury 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 US scientists say it is possible that one single "spike" dose of mercury could be enough to damage a baby or a child's brain, even if there is no further ongoing exposure. With the experiments showing a 20 watt CFL (equivalent to 100 watts ordinary) bulb can produce a spike of 100,000 ng/m3 of air, 300 times the recommended allowable maximum, this could
be a major safety problem with making CFLs the light of choice when ordinary bulbs are banned.
…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.
Sunday, September 27, 2009
Other “Green” Initiatives – Compact Florescent Light Globes - Part 2
Posted by Climate Observer at 27.9.09
Subscribe to: Post Comments (Atom)
Post a Comment