§ Mr. Knowlesasked the Secretary of State for the Environment if he will make a statement on the possible risks of man-made mineral fibres, in the light of the work by the World Health Organisation on this subject.
§ Mr. RidleyA summary report of an international symposium published last December by the World Health Organisation indicates that an increased lung cancer risk was observed in workers involved in the early days of the manufacture of these materials. The DHSS committee on carcinogenicity has reviewed the available evidence for workplace exposure at the request of the HSE and has indicated that exposure to man made mineral fibre (MMMF) should be accepted as having the potential to increase the risk of lung cancer.
The evidence we have shows that, in the MMMF industry, existing safety precautions are keeping fibre concentrations at the point of manufacture well below the limits considered by the WHO at the symposium. Further advice will be offered by HSE on other occupational exposures.
Work has recently begun to assess the extent of domestic exposures. MMMF in the form of glasswool and rockwool constitute the majority of loft insulation materials used in this country. On the limited data so far available, there appears to be negligible risk to the health of householders, either from existing loft insulation installations, or from laying it themselves, or from infrequent visits to their lofts. As a precautionary measure, the Government have work in hand to collect more data, and assess risks. We will give further advice and take action as necessary. Meanwhile, there is no reason for householders to remove MMMF from their lofts, but they should take simple precautions which we have already recommended such as wearing masks and gloves when working in lofts or in other places where the insulation is exposed.
I shall make another announcement when further medical advice is received.