Compact fluorescent bulbs are rapidly replacing incandescent bulbs. Recently, the European Commission opted for a phase out of the latter in the next decade. But now, in one of the Baltic states (Lithuania), an environmental NGO has started a campaign against the increased use of fluorescent bulbs. The reason: mercury.

Mercury is a problem. In industrialized countries there is evidence that present exposure to mercury may increase the risk of fatal coronary disease in older man (1). And current mercury levels in the environment of industrialized countries may also have a negative impact on the development of human embryos, leading to a neurobehavioral deficit of newborns (2). So, there is a case for lowering environmental exposure to mercury. And releases of mercury from compact fluorescent bulbs after they have been tossed into the trash are, to say the least, not helpful in this respect.

However there is more to mercury and lighting than mercury present in fluorescent bulbs. Coal-fired power plants release large amounts of mercury. In principle it is possible to capture such mercury with high efficiency in smoke stacks. Actually, quite a number of waste incinerators in Western Europe do so. But operators of coal-fired power plants are even better than many American bankers in letting others bear the costs of the risks that they cause. So, I have not come across a coal-fired power plant that practices high efficiency capture of mercury. As incandescent light bulbs consume much more electricity than fluorescent bulbs this matters a lot, when the electricity grid is to a large extent fed by coal-fired power plants. In the USA and over the lifetime of one light bulb, the release of mercury is cut by on average about 8 mg when the consumer replaces an incandescent bulb by a compact fluorescent bulb (3).

So is the Baltic NGO wrong? Well, not completely. The point remains that when fluorescent bulbs are tossed in to the trash, mercury will be released. This adds to risk and also leads to the loss of what is by now a very scarce natural resource. To prevent this, a recycling system should be put in place, which allows for the high efficiency recycling of mercury. Deposit-refund systems are known to be conducive to high recycling rates, and such a system for compact fluorescent bulbs would seem a proper basis for mercury recycling.

(1) E. Guallar et al. New England Journal of Medicine 347 (2002) 1747-1754
(2) G. Huel et al. Environmental Health Perspectives 116 (2008) 263-267
(3) M.J. Eckelman et al. Environmental Science & Technology 42 (2008) 8564-8570