PCBs: What are the Risks? -Emergency Preparedness Digest Published by Emergency Preparedness Canada.. Vol 16, No.4, October-December 1989. pp. 23-26. The Emergency Preparedness Digest invited Environment Canada to provide them with facts. The following article is the result of that invitation. Last year's PCB fire at Saint-Basile-le-Grand di more than burn down a warehouse. It fanned the flames of controversy over one of our most troublesome chemicals. As a pall of thick smoke spread across the sky, the evacuation of 3,500 nearby residents began and people had to spend days away from their homes. They could only return after experts had checked for traces of PCBs as well as dioxins and furans, chemicals that can be produced by such uncontrolled PCB fires. By the time the ashes cooled, public attention was focussing not only on the reamining wastes but the thousands of tonnes of other PCBs stil in use or in storage awaiting destruction across Canada. Since then federal and provincial governments have been tightening the regulatory framework and increasing efforts to phase-out, safely store and destroy PCBs. However, a deep public fear of these chemicals sometimes blocks attempts at PCB destruction, particularly incineration. The opposition flared up again this summer when PCB wastes, including some from the Saint-Basile-le-Grand fire, were shipped to Great Britain for incineration. Although Canada had sent other PCBs to Britain for incineration and followed international protocols in this case, the shipment was turned away by British dockworkers. The wastes were brought back to Canada and unloaded at Baie-Comeau, in the face of citizen protests, and at one point, a court injunction. Soon after, the chemicals were trucked, under police guard and against citizen blockades, to a Hydro-Quebec storage sit at the nearby Manic-2 power project. These and other PCB incidents have led to a barrage of news stories, most of which say or leave the impression that PCBs are one of the most toxic chemicals. What are PCBs? Polychlorinated byphenyls (PCBs) are chlorinate hydrocarbons. In the past, thse chemicals were prized for their properties in industrial applications. But scientists discovered starting in the 1050s that PCBs were a health or environmental risk and they accumulated in the food chain. PCBs, which vary from colourless, oily liquids to thick, black resins, are a family with 209 chemical variations (isomers). They were first produced in 1881 and were manufactured in a commercial scale beginning in 1929. None were made in Canada and our supplies were imported mostly from the United States. Because PCBs have a high heat capacity, low flammability and low electrical conductivity, they were widely used in transformers, capacitors, electro-magnets and heat transfer equipment. When used in transformers the PCB level was usually between 60 and 80 percent. PCBs were also added to waxes, adhesives, platicizers, lubricants, caulking compounds, paints, pesticides, inks and carbonless carbon paper. Concern about PCBs rose in 1966 when Swedish scientists testing for DDT found PCBs in wildlife. Since 1972, a series of laws and voluntary restrictions in Canada and the United States have gradually controlled the use of PCBs to closed systems such as transformers, capacitors and electro-magnets. Under the Canadian Envrironmental Protection Act, PCBs are specified on the List of Toxic Substances. Federal and provincial laws prohibit all dispersive used of PCBs, prohibit discharges of PCBs into the environment and require that the chemicals be safely stored. For example, regulations for PCB waste storage on federal property require controlled access, containment to catch any leaks, fire alarm and extinguishing systems for storage sites that are inside buildings, and provisions for cleaning up spills. In addition, a fire control and emergency procedures plan must be developed in consultation with local fire authorities. Similar regualtions cover PCBs under provincial jurisdiction. Although old PCBs can still be used in their original equipment, their days appear numbered. Following the Saint-Basile-le-Grand fire, Canada's environmen ministers announved they intended to accelerate the phase-out of PSCs. How Much Is There In Canada? According to federal surveys about 40,000 tonnes were brought into Canada until a ban on new PCB imports was imposed under the Environmental Contamination Act in 1980. About 19,000 tonnes are in use, mainly in electrical equipment, and another 6,000 tonnes are in storage awaiting destruction. The remaining 15,000 tonnes are unaccounted for. Much of this was used in dispersive uses, such as plasticizers, inks, etc. and has been lost to the environment. Some is likely in pieces of electrical equipment that have not been listed with governments. Before the introduction of strict regulations in recent years, old PCB equipment was scrapped and the contaminated oil was often burned, dumped or even spread on roads as a dust suppressant. According to federal statistics ther are PCBs at more than 4,000 sites, either in use or in storage awaiting destruction. The chemicals are in more than 200,000 pieces of electrical equipment, including 10,000 transformers. PCB transformers are usually mounted inside buildings. The small transformers seen on electrical poles almost never contain high levels of PCBs though they may have some trace contamination. The major users of PCB equipment are electrical utilities, metal and pulp and paper industries. The remainder are scattered across a wide range of locations, including telephone and airline companies, printing plants, computer companies, universities, hospitals, government and office buildings. Three provinces hold more than 80 percent of the PCBs (in use and wastes)-Ontario at 39 percent, Alberta at 23 percent, and Quebec with 20 percent. In addition, thousands of other locations in the country contain small amounts of PCBs. They are buildings with old (pre 1980) fluorescent light fixtures, each of which contains about 30 to 60 grams of the chemical. What Are the Hazards of PCBs? PCBs are a potential health hazard to humans and to other inhabitants of our environment. However, they are less dangerous to handle than a number of other industrial substances such as chlorine or acids. PCBs build up in the food chain in a process called bioaccumula- tion. PCB levels in the water and plant life can be very low, but the chemical resists breakdown in the environment and concentrates in the fatty tissues of living creatures. As one creature devours another, the combined doses of PCBs (and a number of other chemicals) get passed along. Humans are exposed to minute amounts of PCBs from foods, air and water. All humans have a detectable level of PCBs in their body fat and blood, but these levels are not likely to cause adverse health effects, according to Health and Welfare Canada. Health and Welfare Canada has established PCB exposure limits for various foods consumed by Canadians. The departmetn also monitors typical Canadian diets, individual foods, air and water to ensure the public is not exposed to levels that pose a health risk. In parts of the Great Lakes-St. Lawrence ecosystem, PCB levels are high enough in some fish and other aquatic life that people are advised not to consume them. Information on these levels is available from agencies such as the Ontario ministries of Environment and Natural Resources. At the same time research is continuing to assess the health implications of sustained low-level exposure to PCBs. Health and Welfare Canada advises that sustained, high-level exposure to PCBs has been associated with adverse human health effects. These include chloracne, a painful and disfiguring skin condition, similar to adolescent acne. Other effects include eye discharge, swelling of the upper eyelids, muscle spasms, darkening of skin and nails, numbness of limbs, weakness, chronic bronchitis, a depressed immune system, irregular menstrual cycles, and decreased birth weight and smaller head circumference in newborn babies. The internation Agency for Research on Canver recently concluded that there is some evidence to link long-term, high-level, PCB exposure and an increased incidence of cancer, particularly liver cancer. This is based on studies of workers who were exposed to high concentrations of furan-contaminated PCBs. And these chemicals pose a threat to a wide variety of wildlife. Marine and fresh water invertebrates as well as most species and life stages of fish are particularly sensitive to PCBs. Birds also seem especially sensitive. So, it is not just because of direct health hazards but because of their ability to build up through the food chain around the world that PCBs are considered a dangerous chemical and great efforts are being made to prevent their release into the environment. How Should You Handle PCBs? Emergency workers will from time to time face PCBs, either through the inevitable spills that occur periodically, or through more PCB fires. According to Environemnt Canada officials, PCBs in storage are not highly toxic, but should be treated with care. They can be absorbed through the skin, and when, heated, give off vapours that can be inhaled. Anyone handling equipment or drums containing high- level PCBs should wear a face protector, hard hat, coveralls and rubber gloves. If there is a risk of fumes, a resporator should be worn. For more information, federal officials reccommend "Environment Canada's Handbook on PCBs in Electical Equipment", available from bookstores carrying federal publications. In a fire, there is a risk of breathing PCB fumes or the byproducts of combustion which include hydrochloric acid, as well as hazardous dioxins and furans. Environment Canada officials say that smoke from chemical fires in general should be avoided and fire- fighters who must face it should wear protective equipment, including a self-contained breathing apparatus. Clothing and other materials contaminated by PCBs cannot be re-used but have to be treated as PCB wastes and stored until they can be destroyed. What Do We Do with PCBs? There are two accepted ways of destroying PCBs in this country. The first is for low-level PCBs, which usually menas electrical cooling and insulating oil containing less than one percent of the chemical. Decontamination systems already in use mix the oil with sodium under heat to separate the chlorine and create sodium chloride, which is salt. Higher levels of PCBs can be destroyed by high-temperature incineration. Experience in several countries shows that 99.9999 percent of the PCBs can be eliminated if they are burned for two seconds at a temperature of at least 1200 degrees centigrade. The only such permanent incinerator in Canada is near the town of Swan Hills, north of Edmonton, and it is used for Alberta wastes; There are plans to build other fixed incinerators in Canada, but they are still being publicly reviewed. In the meantime, governments are turning to mobile incinerators in hope that the public will accept short-term destruction facilities. The Department of National Defence is having a transportable incinerator shipped to Goose Bay, Labrador, from the United States to burn PCB wastes. This burn, to take place during the winter, will destroy about 40 percent of federal PCB wastes in Canada. The federal government has also indicated that it wants to set up a second mobile incinerator somewhere in central Canada to burn other federally-controlled PCBs. Government spokespersons have said the incinerator could be used to destroy PCBs from other Canadian sources on a cost-recovery basis. In addition, the Ontario government has announced plans to have a U.S. company bring in another transportable incinerator to burn waste PCBs stored nera the town of Smithville in the Niagara Peninsula. The federal, Alberta, Ontario and Quebec governments will co-operate in testing a small mobile incinerator at the site of the hazardous waste destruction facility of Swan Hills, Alberta, to confirm if this equipment can meet the regulatory requirements of the governments involved. Environment Canada Sources on PCBs Environment Canada Headquarters: Commercial Chemicals Branch Hull, Quebec (819)997-1640 Waste Management Division Hull, Quebec (819)997-3377 Environment Canada Regional Offices: Atlantic Region Dartmouth, Nova Scotia (902) 426-3593 Quebec Region Montreal, Quebec (514)283-2349 Ontario Region Toronto, Ontario (416) 937-1055 Western and Northern Region Edmonton, Alberta (403) 468-8041 Pacific/Yukon Region West Vancouver, British Columbia (604) 666-0064 * * * * * * * *