5 March 1986
issue 157 | March 1986
issue 157 | March 1986
PCBs. Do the initials mean anything to you? Probably not. They stand for polychlorinated biphenyls, a chemical compound. But to thousands of Japanese in 1968, PCBs spelled tragedy.
At that time many residents of the Japanese island of Kyusha ate rice oil which had been contaminated with a chemical coolant from a leaking factory pipe. The coolant contained PCBs, a stable fire-retarding substance widely used in electrical transformers.
The afflicted Japanese developed what came to be called 'yusho' - rice oil disease. They suffered from bone deformities, jaundice, loss of memory, hair and sex drive, eye discharge, skin discolouration, respiratory infections and a host of other ailments. The US Environmental Protection Agency (EPA) study of deaths among the Japanese victims showed an abnormally high rate of cancer of the liver and stomach as well as indications that PCB poisoning may cause other cancers.
Polychlorinated biphenyls are a group of organochlorine compounds first synthesised in the 19th century. They are clear, pale yellow liquid, semi-solid or solid substances, their consistency increasing with their chlorination content. They have a mild aromatic smell.
They sound harmless enough. And indeed their stable, fire-retarding properties were good news for the electrical industry, whose products were always dogged by the risk of fire. In the 1930s and 1940s, for instance, there were several mining accidents caused by poorly insulated electric cables. But after the introduction of PCB-insulated cables, accidents decreased.
PCBs were a major breakthrough. Commercial production had begun by the US Monsanto company in 1929 and soon many industrialised countries were manufacturing them, mainly for use in electrical transformers where they are circulated inside to keep the unit cool.
Their use has contributed to our affluence by giving us safer electricity and electrical appliances. Electricity production has been increasing worldwide, going up by about 60 per cent in the years from 1970 to 1979 alone. Those PCB-filled transformers at power stations and on pylons/utility poles feed us domestic electricity in digestible form. And as our standard of living rises, we use more electricity to power the new video, spotlights, freezer and home computer.
What most consumers do not know is that there's a darker side to PCBs. As the Japanese found out, PCBs are poisonous.
In 1943 the New York State Department of Labour published a report on outbreaks of chloracne, dermatitis and deaths due to liver damage among workers handling equipment containing PCBs and similar compounds. 'Both Monsanto and the government were aware of the extremely dangerous nature of these chemicals four or five decades ago, says Lewis Regenstein, author of America the Poisoned, 'but nothing was done to restrict their use until the late 1970s.' At that time, manufacture of PCBs ceased in several countries including the US, UK and Japan, and controls on their use and safe disposal came in.
But already over one million tonnes of PCBs had been produced in the member countries of the Organisation for Economic Co-operation and Development (OECD), the clan of major Western industrialised nations. For PCBs had proved so useful that they featured in a wide range of other products besides transformers. They cropped up in adhesives, paints, printing inks, fire retardants, carbonless copy paper, hydraulic fluid and a range of plastic goods, as well as in fluorescent lights. The chemical was being dispersed far and wide.
Wide dispersal of PCBs was one factor that makes disposal difficult. There's another problem too: because of their stability PCBs do not break down in the environment when we have finished with them. Along with other waste they were normally disposed of in landfills. In the landfill, the harmless-looking poison keeps its potency, unscathed by nature's attempts to break it down. In time it percolates through into the groundwater and taints the streams. Fish ingest it and since PCBs remain stable and are not excreted, the poison accumulates in the fish organs. Anyone eating the fish then builds up a store of PCBs in their own body.
'PCBs are probably present in every species of wildlife on earth,' claims oceanographer Dr George Harvey. Sadly this includes breast-fed babies. An EPA study in 1975 - 76 found that the average US breastfeeding infant was taking in 10 times the EPA's safety level. The baby's small size means that s/he receives 100 times more PCBs per body weight than an adult.
As the dangers of PCBs were more widely known, pressure mounted for them to be withdrawn from use and disposed of safely. This is easier said than done. First you have to find your PCBs.
OECD estimates that member nations had produced over one million tonnes in the period 1930 to 1980. And since PCBs are persistent, most of this tonnage would still be around, somewhere. A totting-up showed that only about half could be accounted for in transformers and similar equipment.
What of the rest? Most of it is 'free in the environment' as the OECD puts it. This means no-one is quite sure where it is - some will have been used domestically in such things as carbonless copy paper or fluorescent lights. Some will no doubt have been dumped and be on its way into the groundwater.
But wherever they end up, PCB disposal is a headache. Landfilling is clearly dangerous. Burning them in an ordinary municipal incinerators at temperatures of about 400 degrees C releases toxic dioxin into the air. High-temperature incineration (about 1000 degrees C) is currently fashionable, but it is expensive and facilities are few. There are some 181,000 tonnes of PCBs currently in use in the EEC, for instance, but disposal capacity can only cope with about 9,000 tonnes a year. Because of the difficulties and expense involved many companies with unwanted PCBs have taken the easy way out they have paid someone to take the toxic menace off their hands, no questions asked.
It's a lucrative business for the illicit 'midnight dumpers'. One enterprising truck driver simply filled his tank truck with PCB-laced oil wastes and abandoned the vehicle in a New York suburb, Obviously it paid him to lose his truck but take the dumping fee.
OECD figures show that a large amount of the unaccounted-for PCBs tonnage was exported to non-OECD countries - the Third World. As late as 1982, Italy was sending PCB-filled transformers to North Africa and the Middle East. Italy has now ceased manufacture, but France and Spain still continue to produce them. Since PCBs are no longer acceptable in the rich world, it seems likely that these PCBs are winding up in the developing countries. Attempts by the NI to find out just where today's PCBs go met with little success. The UK's Hazardous Waste Inspectorate did not know that the countries concerned were still manufacturing them. The French distributor, Prodelec, appeared helpful on the surface but it proved impossible to speak directly to anyone who could answer our enquiries. Former manufacturers Bayer and Monsanto were unable to help.
So it appears that the legacy of our affluence is likely to persist in poor countries for many years, with more incidents of contamination. In the West we have begun to deal with the problem of PCBs at official levels, spurred on by public outcry. But what is going to happen in countries where the infrastructure doesn't exist to test for PCBs poisoning, where no high temperature facilities exist to dispose of the killer compounds, and where people handling the chemical probably do not know of its toxicity? We can sit tight and wait for another Kyusha tragedy, or we can press for the manufacturers to take up the responsibility for supervising safe disposal of PCBs in countries of export. It's not enough just to clean up our own backyard.