§ 2.40 p.m.
§ LORD DOUGLAS OF BARLOCHMy Lords, I beg leave to ask the Question which stands in my name on the Order Paper.
§ [The Question was as follows:
§ To ask Her Majesty's Government whether any steps are being taken to limit the lead content of drinking water to the International Standard Limit of the World Health Organisation, namely 0.05 milligrams per litre (approximately one ten-thousandth of an ounce per pint).]
§ THE PARLIAMENTARY SECRETARY, MINISTRY OF HOUSING AND LOCAL GOVERNMENT (LORD KENNET)My Lords, the responsibility 628 for securing a supply of pure and wholesome water lies with the statutory water undertakers. As to safeguards against an excessive lead content and other impurities, my right honourable friend's predecesors for many years have advised undertakers to carry out chemical examinations of the water they supply; and they do so. Where they consider that the nature of the water demands it they reduce the acidity by alkali treatment; or they can prohibit, by means of bylaws, the use of lead pipes. Moreover, an independent check is performed by medical officers of health who take their own samples to test water purity. My right honourable friend considers that adequate safeguards exist and that the water supply underakers are well aware of the existence of this problem. He therefore sees no case for prescribed standards. I am, of course, aware of the correspondence on this subject in the Lancet; but since the chemistry involved is rather complicated, I suggest to my noble friend that I should write to him in greater detail.
§ LORD DOUGLAS OF BARLOCHMy Lords, may I ask my noble friend whether his reply indicates that in fact the water supplies of this country conform to the recommendations of the World Health Organisation, or are very near to them?
§ LORD KENNETMy Lords, it is difficult to answer "Yes" or "No" to that question, because the variable in this matter is not so easily controlled at the level of how much lead there is in the water but rather at the degree of acidity of the water, since it is acidity in the water which is capable of dissolving the lead in the pipes, and there may be lead pipes anywhere.
LORD SALTOUNMy Lords, may I ask the noble Lord a question in this connection? This information is rather surprising to me, because I have always understood that it is pure water that dissolves lead and that the best way to stop water taking up lead was to adulterate it a little. Is that not the case?
§ LORD KENNETMy Lords, I said that the chemistry was complicated. While I am ready to do my best to pursue this matter this afternoon, I would suggest that if I write to my noble friend to answer his Question more fully perhaps I could send the noble Lord a copy of it.
§ LORD DOUGLAS OF BARLOCHMy Lords, may I ask my noble friend whether it is not the case that the ability of the human body to excrete lead is extremely limited and that comparatively small amounts will build up to a toxic level; and is that not the purpose of the Standard Limit of the World Health Organisation? Secondly, does it not appear from recent papers in medical journals that lead poisoning is more common than might be supposed and that cases might remain undetected for many years, and perhaps for ever?
§ LORD KENNETMy Lords, it is true that it has been known that cases have gone undetected, but I would not agree that the recent reports of three cases, spread over a good many years, which appeared in the Lancet indicate a high incidence of this condition.
§ LORD LEATHERLANDMy Lords, in view of this Question, I wonder whether my noble friend could give the public an assurance that even though there may sometimes be slight impurities in the water, there is sometimes arsenic even in beer, and that in both cases there is no danger to the public if they consume them.
§ LORD KENNETMy Lords, here we are talking about the general level of purity of British water supplies, and I can give the House and public the assurance that it is not had and is getting better all the time.
§ LORD DOUGLAS OF BARLOCHMy Lords, may I ask my noble friend whether, in this connection, it is not necessary to have regard to other sources of intake of lead, such as lead additives in motor fuels and lead deposits from polluted atmospheres?
§ LORD KENNETMy Lords, that is another question, of which I should require notice.
§ BARONESS SUMMERSKILLMy Lords, I wonder whether the noble Lord could say how many areas have introduced by-laws to prohibit the use of lead pipes.
§ LORD KENNETNot without warning, my Lords.