Lead Pollution (Hansard, 7 March 1979)

§ Mr. Denis Howell

Yes. The text of the letter is as followsI promised to write about the points you raised in the lead debate on 12 December which there was not time to cover in my reply. I think there are five main headings: the Gravelly Hill study; the total amounts of lead in vehicle emissions; the Warren Spring multi-element survey; privately financed Harwell research; and the Harwell study of lead from motor vehicles. Your points about the Membership of the Lawther Working Party and about the report to DHSS on recent evidence on lead and child health by doctors at Great Ormond Street are for the Secretary of State for Health and Social Services, and I have drawn his attention to them. You have criticised the survey techniques used in the Gravelly Hill study. It is true that the response was much better in Sutton Coldfield than in the more central areas. The report is entirely frank about this and about the reservations there must be about the results obtained for the inner city children. One of the central conclusions of the report, set out in paragraph 107 is that "a problem [of relatively high blood lead levels amongst pre-school children in the inner zone] exists; its scale will not be known until we have more data". As you know the Working Party which is following up the report is setting in hand further surveys. The reason the response in the inner areas was poor was that it is difficult to get the people who live there to take their children in surveys of this kind to a hospital—any hospital—to give a blood sample. The report details the considerable efforts that the team made to publicise the survey, to offer transport and visit people to persuade them to take part. Good Hope hospital was used because it was the one made available by the health authority. In retrospect, it would have been better, and again the report says this, if one of the more central hospitals had been used; but it is a matter of opinion whether it would have made all that much difference. In the further surveys it is planned to take samples in people's homes, although this procedure does create problems of possible contamination of blood samples which the earlier survey wanted to avoid by taking them in the hospital. 698W Turning to the total amount of atmospheric lead from vehicle emissions, the reduction in the permitted lead level to 0.40 m/1 in January 1981 will keep the amount used in petrol below the 1971 level of 10,000 tonnes per year—at least until 1985, on the basis of current forecasts of growth in traffic. This is in line with the Government's present policy of containing total lead emissions. As I said in the House, the Government has in hand a detailed study of the options for further reduction, including going down to the German level, or taking lead out altogether. The Warren Spring "multi-element" survey was designed to measure general background levels at a variety of urban sites, rather than specifically kerbside exposure. People do, of course, frequently live and work in buildings at the heights you quoted. One of the problems with siting monitors lower down is that they are very frequently vandalised. However, Warren Spring are carrying out a separate study of kerbside concentrations. The results will be available in due course, in the usual way, and I will see that you receive a copy. The UK industrial midlands report you referred to was a laboratory draft report on a study of the concentrations of metals in the atmosphere at several Midlands factory sites. I have asked Warren Spring to issue the report, and it should be available shortly. You also asked about the Harwell studies commissioned by industry and referred to in a Parliamentary Reply on 30 November 1978. Whether such studies are published is a matter for the companies concerned, to whom the reports belong, and for Harwell. However, I gather that one of the studies will be available from Harwell in a week or so: this is the study I referred to in my reply on 24 January to your question and is of lead pollution in West London. (The sponsors, Associated Octel have already sent copies to the local authority and to those involved in the current legal action against them and the oil companies.) I understand that the other study you asked about has been submitted to "Nature" for publication. I am glad that you now accept that it was always the intention that the Harwell report on lead from motor vehicles should be published. I would only add that there was no reason for academic colleagues to conclude that the work was secret: I understand that Dr. Chamberlain told them that he would prefer that the findings should not be discussed, except with those whose work was quoted in the report, until it was published and freely available. The point you referred to about the assumptions in the report on lead intake from food, on the rate of gastro-intestinal absorption, and on average air intake have been taken up by Dr. Chamberlain in his reply to Dr. Bryce-Smith in the "New Scientist" of 21 December. The correspondence is continuing. The report is among the evidence being assessed by Professor Lawther's working party. I hope I have covered in this letter and in my reply to the debate the points you have raised. Let me know if there are any others.