Starting in 2012, stores across Canada will begin phasing out the sale of incandescent light bulbs under the terms of a federal ban announced in 2007. The ban is expected to reduce greenhouse gas emissions by more than six million tonnes a year and save homeowners about $60 annually in electricity costs.

Compact fluorescent bulbs are vastly more efficient. They use up to 75 per cent less energy than incandescent bulbs, which means reduced greenhouse gas emissions from energy plants. Fluorescent bulbs also last up to 10 times longer.

Fluorescent bulbs are extremely energy-efficient, using up to 75 per cent less energy than incandescent bulbs. (Associated Press)

The effects of the ban on incandescents are already being felt in British Columbia, which is a year ahead of the rest of the country with its provincially mandated phaseout having begun in January 2011.

Both the federal and provincial moves dovetail with those of other jurisdictions around the world. In 2007, Australia became the first country to ban the incandescent bulb, followed shortly after by the European Union. As of Sept. 1, 2009, the EU ended the manufacture and import of 100-watt and frosted incandescent light bulbs. Clear bulbs will be banned progressively, until all traditional bulbs disappear from stores across Europe in 2012.

The reason such bans have been introduced is because of the technology used in each type of light bulb.

Incandescents work by heating a filament inside a tube until it is white hot and gives off light. But more than 90 per cent of the energy involved in that process escapes as heat.

Fluorescent bulbs, on the other hand, use only a small amount of electricity to excite the gas (mercury vapour) inside the tube. The gas then gives off invisible ultraviolet light, which bounces off the phosphor coating inside the bulb to produce visible light.

While there is no debate over the merits of fluorescent bulbs when it comes to greenhouse gas reduction, there is rising concern over their disposal because they contain mercury.

The problem with mercury

Chronic exposure to mercury — a naturally occurring element and a known neurotoxin — can damage the brain, spinal cord, kidneys and liver.

"Mercury can impair the ability to feel, see, move and taste and can cause numbness and tunnel vision. Long-term exposure can lead to progressively worse symptoms and ultimately personality changes, stupor and in extreme cases, coma or death," according to Health Canada.

Further, Health Canada says recent research suggests that even at low levels, mercury can have adverse health impacts on the cardiovascular and immune system.

While no mercury is released when the bulbs are in use, taking precautions when throwing them out is important. The U.S. Environmental Protection Agency estimates that three per cent of the total mercury in discarded fluorescent lamps is released to the atmosphere when they break during transportation to a disposal facility. Other researchers estimate emissions are as high as 17 per cent.

If a fluorescent bulb ends up in a landfill, the mercury can leech into the surrounding soil or be released into the atmosphere. If it is incinerated, the amount of mercury released into the atmosphere may be higher, according to Health Canada.

While fluorescent bulbs contain about five milligrams of mercury — less than in a watch battery, according to Natural Resources Canada — Health Canada recommends that items containing mercury be treated as hazardous waste.

Disposal varies across country

In Canada, the provinces are responsible for setting regulations around the disposal of household hazardous waste, but municipalities most often carry out the actual disposal.

Disposal programs vary from municipality to municipality, with some offering collection programs specifically for mercury-containing products, such as fluorescent bulbs, in which the mercury is captured and recycled. Other municipalities collect mercury-containing products as part of their general household hazardous waste program.

Not surprisingly, the Federation of Canadian Municipalities has said it would like manufacturers of fluorescent bulbs to assume the cost and responsibility for recycling them.

But new research suggests there may be a way to avoid the problem of mercury disposal altogether. McGill University scientists, for example, are experimenting with a new type of light bulb that uses electrodes made of carbon nanotubes, which would allow mercury to be replaced with water.