§ Mr. Torneyasked the Secretary of State for Social Services if she has any further information on tests being carried out in Great Britain and the United States into any possible risk of cancer from the long-term use of certain hair dyes.
§ Dr. OwenFurther to my reply to my hon Friend on 8th July—[Vol. 895, c.108–9]—I apologise that it was not clear from my initial answer that the statement that early indications are that tests are proving negative did not refer to the study conducted by the University of Birmingham but to long-term American tests.
Two areas of research are involved, studies of mutagenicity and studies of carcinogenicity. As to the first, studies on the mutagenic effects of certain hair dyes on bacteria have been carried out at the University of Birmingham and elsewhere in the United Kingdom, and the results have been published. Similar studies have been carried out in the United States, and the Department's medical advisers have examined the results. Although mutagenic effects were observed in both sets of studies it is not yet possible to be certain about the relevance of such effects for human health.
The Department's medical advisers have studied carefully the results of long-term American tests in animals for cancer which they consider to be far more relevant in which some of the dyes subjected to mutagenicity testing have been used. So far they can find no evidence 296W that they produce cancer. Similar long-term studies using the remainder of the dyes subjected to mutagenicity testing are in progress, and the Department's medical advisers will examine the results of these studies as soon as they become available. The study conducted by the University of Birmingham to which I referred in my earlier reply is one of these.