The dangers associated with the inhalation of asbestos fibres have been known for more than 20 years. Governments and industries have introduced regulatory measures requiring safety controls throughout the product lifecycle to limit asbestos exposure to the general public and workers. Only one fibre is now mined, chrysotile, and experience has demonstrated that it can be used safely, if recommended work practices are followed. And yet the controversy still persists. Why?
1. Because in some countries, the number of cases of lung cancer
and mesothelioma continues to grow.
Despite standard dust levels that have been in existence since the 1970s, the number of asbestos-related deaths in some countries is rising. This suggests that controls are ineffective. In fact, this is not the case at all.
An important feature of all asbestos-related diseases is the latency period: it takes 20 to 40 years for the first symptoms to manifest. Those affected today were exposed to large quantities of fibres, sometimes more than 100 f/cc up until the 1970s. These levels, mostly a result of workers installing extremely dusty sprayed-on (friable) asbestos insulation materials, were 100 to 200 times higher than currently regulated exposure limits in most countries. In addition, more hazardous amphibole varieties of asbestos were frequently used at the time. So, for the next fifteen years or so, cases linked to past exposure will continue to accumulate, mainly in cold-weather countries where these materials were used extensively. It will take another fifteen years beyond that before we begin to see the benefits of modern chrysotile control measures and the ban on amphiboles and friable products, which were introduced in the 1970s.
2. Because friable asbestos is still present in millions of
buildings today
After World War II, construction sites, especially in Europe and the United States, routinely used asbestos-based insulation products, which were sprayed on. The asbestos fibres (chrysotile, crocidolite and amosite), amalgamated with a liquefied binding agent, were applied directly on site, and sprayed onto walls, support beams and pipes. Talk about dust! Yet they were very popular materials because they protected against fire and afforded good thermal and acoustic insulation. They were used extensively in colder climates, to insulate commercial and administrative buildings, as well as factories and shipyards. For cost and technical reasons, builders often chose amphibole asbestos-based materials to insulate pipes and boilers. Starting in the 1970s, countries gradually banned the use of amphibole and sprayed-on friable insulation because of the high risks to workers.
And the problem has not gone away: it was all very well to ban all new uses of friable asbestos, but hundreds of thousands of buildings are still insulated with these fibres. And that is where the problem lies not with the chrysotile-cement being manufactured today. The friable asbestos installed in buildings is still a potential hazard and can endanger the health of maintenance and repair workers if they do not follow appropriate work practices.
The alarming statistics on asbestos-related diseases and the poor management of friable asbestos products in buildings have attracted attention. Pressure groups and the media have triggered a veritable panic and made asbestos "Public Enemy #1". People have difficulty believing that there is a safe exposure level, a threshold below which there is no danger. They also have difficulty distinguishing the risks to building occupants, which are nil when the product is in good condition, from the higher risks incurred by workers if they handle the product without taking due precautions.
In response to public opinion, governments in some countries have introduced extensive product prohibitions, retaining only products for which there are no suitable substitutes. In Europe, ten countries have chosen this path, among them France, Germany, Austria, Switzerland, Italy as well as the Scandinavian countries. In these countries, which included some of the heaviest users of sprayed insulation and amphibole fibres, asbestos represents one of the major causes of industrial disease.
But bans will not eliminate the problem. What needs to be done? Is the immediate and total removal of all in-place friable asbestos insulation the solution?
NO - says the Health Effects Institute-Asbestos Research (HEI-AR)
In 1991, this eminent American institute concluded that, in buildings which are routinely maintained, asbestos insulation does not appear to affect the health of occupants. There is insufficient proof to justify the systematic removal of intact materials. The Institute arrived at this conclusion after years of research ordered by the U.S. Congress and conducted by independent scientific and technical experts. According to their measurements, the level of asbestos fibres in the air of buildings is about 0.00027 f/cc, not significantly different than the levels normally found in ambient air, and thousands of times lower than today's regulated occupational exposure levels. The same working committee also compared cancer risks to buildings occupants with other types of risks:
| Occupant of a building containing asbestos | 0.04 |
| Radon, indoors | 2-5 |
| Tobacco smoke (secondary exposure) | 5-20 |
| Other lethal risks: | |
| - being struck by lightning | 0.3 |
| - eating a charcoal-broiled steak once a week | 0.1 |
| - smoking | 2,190 |
NO - says France's Académie nationale de médecine
The immediate and universal removal of all asbestos from public buildings would be an operation of massive proportions. Experience has also shown that in many cases removal is in fact dangerous to the environment unless the strictest safety precautions are taken. The cost in France alone would come to several billion francs. If such a decision were necessary to protect the health of occupants, evidently it would have to be done, regardless of the cost. But that does not seem to be the case (April 1996).
The United States originally took the same line as France. Under pressure from the media, the Americans first opted for a radical approach. But, for several years now, their experience has shown that the majority of systematic removal measures are very expensive with no objective improvement in health, either in the long or short term. Since then, they have opted for a management and control strategy for buildings insulated with asbestos.
NO - says the U.S. Environmental Protection Agency (EPA)
In its guidelines for managing buildings containing asbestos materials, the EPA endorses the following principles:
Must there be a total ban on the use of asbestos?
NO - says the U.S. Court of Appeals
The EPA did try to ban most uses of asbestos. However, upon review by the U.S. Court of Appeals, it was found that banning asbestos would do more harm than good. The Court found EPA's support for a ban deficient in several major ways. Firstly, the EPA failed to explore less burdensome alternatives to a ban. More specifically, it virtually ignored the feasibility of a controlled-use approach. Secondly, the Court criticized the EPA for ignoring the enormous costs of a ban. For example, the EPA argued that a ban of asbestos-cement pipe could hypothetically save about three lives over the next thirteen years, at a cost of between 128 to 227 million dollars or $43 to $76 million per life saved a price tag even the EPA admitted was high. The Court noted that the extremely high costs of banning asbestos in relation to the trivial benefits was unreasonable in comparison to other "less burdensome" regulatory options. Thirdly, the EPA failed to consider whether adequate substitutes were available for banned asbestos products and if there were substitutes, it did not demonstrate that these were necessarily safer than asbestos. Clearly, the EPA had not done its homework, and for this, the Court reprimanded it severely. In fact, the Court concluded that a ban of asbestos "may actually increase the risk of injury Americans face". For all of these and other reasons, the Court of Appeals ruled that the ban should be vacated in its entirety.
NO - says the French Académie nationale de médecine
Although the public might view this favourably, a total ban on asbestos would change nothing. In the Académie's analysis, a ban would not resolve the problems caused by the material's presence. Indeed, it is likely that a ban would sustain the mistaken impression that all asbestos-related problems had been solved, resulting in carelessness during renovation or demolition.
In conclusion