Mercury in Vehicles
Mercury-containing switches control vehicle convenience lighting (turning the hood and trunk lights on and off) and some anti-lock brake systems. These switches account for more than 99% of the mercury in automobiles today, with the other one percent found as a gas in high intensity discharge (HID) headlamps and navigational displays. Each switch contains just less than a gram of mercury, but cumulatively they amount to 13 to 15 tonnes of mercury in vehicles on the road in Canada today. Mercury in automobiles is the single largest source of mercury in use in Canadian products.
Import auto makers ceased using mercury switches in the mid-1990s, and North American auto makers began phasing them out in 1995. It wasn't until model year 2003 that mercury switches finally stopped being used in new cars. This represents a huge step forward for the North American auto manufacturing industry, but there is a 10-15 year legacy of mercury switches that needs to managed.
General Scrap in Regina has a program to encourage the removal of mercury switches from automobiles being prepared for recycling. Automobile recyclers remove the switches and give them to Wheat City Metals. SaskPower pays a bounty on the switches to keep them out of the recycling stream. Between 2003 and 2007, this program removed 170,000 mercury switches and prevented 195 kg of mercury emissions.
Cars have yet to become mercury-free. No manufacturers have yet agreed to eliminate mercury from HID headlamps--the use of these lamps is actually increasing. Mercury is also found in navigational displays, a feature which is becoming more and more popular in new automobiles .