Push to replace mercury thermometers is going global
By Judith D. Schwartz
Environmental Health News
December 5, 2008
Over the last decade in the United States and Europe, the mercury thermometer has gone the way of the rotary dial phone and analog television: virtually phased out.
Now the effort has gone global.
At a conference in New Delhi on Friday, international officials announced a global partnership to eradicate mercury in health care facilities worldwide. This initiative, coordinated by the World Health Organization and Health Care Without Harm, aims to replace 70 percent of all mercury thermometers and blood pressure devices worldwide with digital and aneroid alternatives by 2017.
It’s not just a quixotic dream, said Dr. Peter Orris, chief of environmental medicine at the University of Illinois at Chicago Medical Center. There are safer, more sustainable alternatives. Three or four years ago, he had to make a case to people in the developing world for giving up mercury devices. “Now,” he said, “people are coming to us.”
In the United States and Europe, regulations and efforts by environmental groups have prompted many hospitals to stop using medical devices that contain mercury. Thirteen states, including Illinois, Washington, Maine, Minnesota and California, have state laws prohibiting or restricting the sale or distribution of mercury thermometers, according to the U.S. Environmental Protection Agency.
Elsewhere, the Philippines is the first country in Southeast Asia to take the “no mercury in healthcare” pledge, and efforts have begun in several countries, including Taiwan, Mexico, Argentina, and South Africa.
Mercury-based thermometers are still used throughout the world, particularly in pediatrics. In any given hospital, thousands of thermometers may break over the course of a year, releasing mercury, a potent neurotoxin that spreads globally via the air and waterways.
Before its switchover to non-mercury instruments began, Argentina’s health care system discharged close to one metric ton of mercury into the environment through thermometer breakage every year, according to a report by Orris and colleagues published in May in the World Medical Journal. Sphygmomanometers, used to measure blood pressure, are less prone to break, but have larger mercury reservoirs and can leak.
Direct exposure to mercury vapors can be immediately dangerous, harming the brain, kidney, heart and lungs. In the environment, elemental mercury becomes methylmercury, which accumulates worldwide in tissues of fish and other wildlife as it moves up the food chain. Methylmercury has been linked with neurological effects, primarily IQ reductions, in fetuses and children, and some studies suggest that it might cause cardiovascular and immune effects, too.
Health care is a small source of mercury emissions. Much bigger culprits include coal-fired power plants, fossil fuel extraction, waste combustion and incineration, battery disposal, manufacture of chlorine and gold mining. U.S. coal plants, for example, spew 48 tons per day into the air, according to the EPA.
Yet health care uses can still have a significant environmental impact. Prior to the phase-out in the United States, hospitals contributed an estimated 4 to 5 percent of all mercury feeding into wastewater; thermometers alone accounted for 15 metric tons of the metal relegated to solid waste landfills.
“Other industries do a lot more. But this is an important place to start,” said Joshua Karliner, international coordinator for Health Care Without Harm, which is playing a major role in the global initiative, a component of a broader United Nations Environment Programme mercury project led by the EPA. “It’s still significant. And there are clear, affordable alternatives.” Once medical personnel realize the threat posed by mercury, he said, they can “raise the warning flag” in their countries.
In developing nations, mercury spills may not be properly cleaned in a timely way and instead are flushed down the drain and into the water system, incinerated, or dispatched to a landfill. One study of New Delhi hospitals by the Indian environmental group Toxic Links, a co-sponsor of the New Delhi conference, found a “substantial presence of mercury in ambient air” inside the hospitals. The levels exceeded several international safety standards. The room used to calibrate sphygmomanometers, in particular, was described as a mercury “hot spot.”
Indeed, the presence of mercury in a hospital setting is not limited to thermometers and blood pressure devices.
Nancy Mulvihill, vice president of not-for-profit Covenant Health Systems, a Catholic health care network with 20 facilities in New England, discovered this three years ago when Covenant pledged to eliminate mercury from all locations wherever possible. “It took a year, because mercury was in so much of what we used—thermometers, blood pressure devices, even the thermostats on the wall and fluorescent bulbs,” Mulvihill said.
The WHO/Health Care Without Harm partnership focuses solely on thermometers and sphygmomanometers, which are widely used and have viable alternatives.
Shifting to alternative thermometers is fairly straightforward, as digital thermometers are accepted as accurate and easy to use. The concern has been the cost, as the new thermometers have been more expensive. As of 2006, digital thermometers cost three times more than mercury ones in Mexico and Argentina and eleven times more in China.
However, with greater quantities produced, the price has decreased. According to Orris, once hospitals calculate the cost of mercury thermometer breakage and cleaning up after the breaks, the switch becomes a minor budgetary issue.
Encouraging people to invest in digital thermometers for home use is still a challenge in the developing world, Orris said. But mercury thermometers are largely being phased out so they are harder to find. China and, to a lesser extent, India are now the only countries making them. If a thermometer has a silver bulb, it contains mercury; if the bulb is any other color, it is mercury-free.
Blood pressure devices have been a tougher sell due to uncertainty about accuracy, said Orris. One factor is that non-mercury sphygmomanometers need to be calibrated four times a year compared with once or twice for the mercury instruments. When used properly, they are accurate, but in many cases, health care workers were not calibrating them.
Orris added that the quality of sphygmomanometers varies greatly by manufacturer, and that claims of dependability do not necessarily stand up. He recommends purchasing blood pressure units that have been evaluated by an impartial third party. Accurate models are out there, he stressed.
“It turns out that the biggest inaccuracy with blood pressure devices is the people doing the measuring.” For example, he said, with the dystolic measurement, people often wait for the tone to disappear, which means recording an inaccurate figure. Ongoing initiatives include training health care workers in the use of non-mercury devices, said Karliner.
On Thursday, business leaders, health care providers and multilateral aid agencies met in New Delhi and agreed to promote production of accurate, affordable, mercury-free medical devices. Karliner said he is confident that the movement is “taking hold quickly around the world.”