Document a4EGBkxOGjYJ1ZxqJwNdzVe3y

New Scientist 25 October 1979 2S1 Controlling cancer--asbestos shows the way New safety standards for asbestos, Lawrence McGinty recommended in a report published causing no ill effects. But more and more, yesterday, are more than they appear: both the H'SC and HSE face the problem the thinking behind them will almost of setting standards for cancer-causing certainly dominate the setting of future substances (such as asbestos) which have standards for all cancer-causing sub no such "threshold": they have some stances in the workplace. effect, however small, even at very low The long-awaited report (Asbestos: concentrations. Final Report of the Advisory Committee, The philosophy adopted by the advi vols 1 and 2, HMSO, 5 each), recom sory committee to escape this trap is mends tighter safety standards for the three fold. First, it says, manufacturers three main types of asbestos. It says blue and users of asbestos should have a duty asbestos (crocidolite) is so dangerous that "to consider the substitution of asbestos the current voluntary. ban should be by other materials so far as it is reason strengthened by law. Concentrations of ably practicable to do so". The Health white asbestos (chrysotile) in the work and Safety Executive, or the Commission, place should be kept as low "as is reason should issue general advice on substi ably practicable" and, in any case, lower tutes to help manufacturers decide than 1 fibre/millilitre in the air that whether asbestos is the best material to workers breathe. Similar strictures use. This falls far short of the measures should apply to brown asbestos (amosite), the TUC, representing the unions point says the report, except that the control of view, demanded in its evidence to the limit for this type of asbestos should advisory committee--it wanted the HSE be 0-5 fibres/ml. In all cases, employers to enforce a policy of gradual compulsory and users of asbestos should be obliged substitution. to consider safer alternatives. The second part of the advisory com The thinking behind these standards mittee's approach is to replace "safety Removing blue asbestos dumped next is new. It closely reflects the philosophy standards" by "control limits". This to a playground in London of safety standards for radiation set out recognises that even very low concentra by the International Commission on Radiological Protection. Indeed members of the Advisory Committee on Asbestos read ICRP Report 26, which expresses the commission's thinking. The logic behind the recommended standards is a way out of a bind that increasingly traps the Health and Safety Commission (HSQ and Executive (HSE), which are responsible for safety at work. Traditionally, so the theory goes, safety standards in industry were set on the basis of scientific evidence which showed, for any particular substance, how low concentrations of it had to be before tions of asbestos can cause cancer--there are no "safety limits". Instead the advisory committee recommends "con trol limits"--the "upper limit of per mitted exposure". Above this limit, the risks resulting from exposure would be "unduly high". Below the limit, risks would still exist, but they would not be unacceptable in all circumstances. Whatever the arguments for or against this philosophy, the advisory committee's specific recommendations for control limits for asbestos are sure to run into a barrage of opposition from scientists and trade unionists. First, its advocacy asbestos in the air--assumptions which not all researchers share with the advisory committee. In any case, trade unionists are hardly likely to be happy with a control limit which could, con ceivably, mean that 310 of the estimated 25 000 workers currently exposed to asbestos will die from diseases caused by their work. Neither does the report say anything at all about very small asbestos fibres--: too small to be seen by the present .microscopic methods of analysis. Some researchers believe that these fibres could prove dangerous--yet the control Observer of different standards for different types limits the advisory committee recom of asbestos contradicts a strong current mends ignore fibres that the light in scientific thinking. Irving J. Selikoff, microscope cannot see. of the Mount Sinai School of Medicine in The third pillar of the advisory com New York, who is probably the US's mittee's recommendations is that all ex leading asbestos researcher says: "It is posures to asbestos should be as small now generally conceded that . . . dis "as is reasonably practicable". Thus the tinctions as regards the need for con control limit is merely a "maximum" trol should not be made solely on the limit--the duty to reduce exposures to grounds of [fibre] type". In his evidence the minimum is overriding. Again, how to the advisory committee, Julian Peto, ever acceptable this approach may or a prominent asbestos researcher from may not be in theory, its practical appli Oxford University, specifically attacked cation by the advisory committee is the idea that chrysotile does not cause almost certain to leave many trade cancer of the lining of the lung or unionists dissatisfied. abdomen (mesothelioma). Yet the advi The advisory committee assessed what sory committee set a laxer "control limit" concentrations of asbestos are "reason for this type of asbestos, largely on the ably'practicable" to achieve in the asbes grounds that it "rarely" causes meso tos industry by calculating, in broad thelioma. terms, what measures the industry could The advisory committee sees a control afford. But in this task it relied almost limit of 1 fibre/ml for chrysotile as entirely on figures and estimates that the acceptable because exposure to this level industry itself provided--a procedure every day for 50 years would cause be hardly likely to inspire confidence. tween 0-02 and 1-25 per cent excess The advisory committee's report will deaths among workers so sexposed. But now go to the Health and Safety Com the accuracy of these figures depends mission which, in time, will issue draft crucially on assumptions about the regulations for comment So the report accuracy of past methods of measuring by no means ends the asbestos saga. | _ . 1 7`t 5