§ 7. Dr. Strossasked the Minister of Health, as representing the Lord President of the Council, what information he has received from the Medical Research Council on the possibility of selective damage which the chromosomes may suffer from low levels of radiation from ionising rays; what research is being conducted on this problem by the Medical Research Council; and whether he will make a statement.
§ Mr. VosperThe Medical Research Council are supporting an extensive programme of research on the effects of exposure to low levels of ionising radiations. Chromosome damage, as distinct from gene mutation, appears to be induced only rarely by long continued exposure to radiation of low intensity. Research on this problem is continuing and the results will be published as they become available.
§ Dr. StrossIs the implication of the Minister's answer that in certain circumstances it is possible for the chromosomes to be damaged from only low levels of radiation if long sustained? Does that not mean that we should be especially careful in protecting the public from any extra ionising rays?
§ Mr. VosperI understand that the damage to chromosomes from low level radiation is extremely slight indeed. As the hon. Gentleman will realise, it is very difficult to carry out experiments on this.
§ Dr. SummerskillWill the right hon. Gentleman publish in the OFFICIAL REPORT the names of the members of the Council who are engaged in this work?
§ Mr. VosperI will see whether that can be done.
§ Mr. MasonCan the right hon. Gentleman say to what extent the Medical Research Council is conducting a survey of the effects of radiation on people who are subject to a higher background of radiation solely because of where they are living?
§ Mr. VosperI think that comes into the researches of the Medical Research Council, but it does not particularly follow this Question.
§ 8. Dr. Strossasked the Minister of Health, as representing the Lord President of the Council, by how much the expectation of life is reduced as a result of exposure for ten years to the maximum permissible ionising radiation to which workers in radioactive substances may be exposed.
§ Mr. VosperThere is very little evidence regarding the possibility that exposure to radiation may affect the expectation of life in man, and it is therefore impossible to estimate the effect in this respect of any particular dose. The present recommended maximum permissible levels have been chosen as providing a substantial margin of safety below the minimum dose known to produce any effect.
§ Dr. StrossIs it not suspected, however, that ten or fifteen years' work at the maximum permitted dose would reduce the expectation of life by about eighteen months?
§ Mr. VosperAs the hon. Gentleman again knows, there is a great variety of medical opinion about this. I would not wish to accept that estimate as being the correct one. It could well be less.
§ Mr. BlenkinsopWould the right hon. Gentleman consult his right hon. Friend the Minister of Labour about issuing regulations on this matter and state what progress has been made?
§ Mr. VosperI will note that point.