I have many points to deal with. I cannot give way.
It is particularly the effect on children that makes the health case for taking this action now. As I said on 4th March, it is the total intake that is important.
The hon. Member for Northwich (Mr. Goodlad) asked about the evidence. I answer that question, as the hon. Gentleman graciously conceded. The paper on which we rely was prepared by Dr. F. W. Alexander, Dr. H. T. Delves and Professor Barbara Clayton. It says that children are believed to absorb lead at a higher rate than adults and are therefore at greater risk from lead from all sources. Moreover, lead from petrol can get into people, particularly children, other than by breathing in lead in the air.
The fact remains that the only potential source of the intake of lead into the human system that we have it in our power to reduce now is the lead that we put into petrol. That is the case for taking direct action. Professor Barbara Clayton advised us to do so to keep things as they are and not let them become worse—in other words, to make sure that the emissions of lead into the atmosphere are kept at 1971 levels. That is precisely what the Government's proposals are. It would be grossly irresponsible of the House to depart from that medical advice and programme.
I come now to the economic considerations. This matter was raised earlier by a number of right hon. and hon. Members, including the right hon. Member for Knutsford (Mr. Davies) who, very generously, has not sought to speak tonight, thus allowing others to have their turn. Removing lead from petrol means that there is a higher oil requirement. That means either that we import more oil, or, as North Sea oil becomes available, we export less of it. Either way, it has an effect on our balance of payments. The point is that when North Sea oil is flowing, our balance of payments position will be stronger and we shall be able to afford to pay more. For this reason, equating the health argument with economic considerations, the Government have decided to come down to the recommended level of ·40 grammes per litre by 1981 in three stages—to ·50 grammes as soon as possible, to ·45 grammes by 1978, and to ·40 by 1981. My only regret is that the balance of payments position does not enable us to meet that target sooner than 1981. On a realistic assessment, the Government have just about got it right.
It is true that the Germans have moved beyond ·40 grammes, to ·15 grammes per litre. This brings me to the important question asked by my hon. Friend the Member for South Shields (Mr. Blenkinsop) about the effect on the British car industry if we do not follow the European example. The answer is self-evident. Unless British manufacturers are encouraged to manufacture engines capable of reaching the standards demanded in Europe and the United States this is bound to have an adverse effect on their future export prospects. That was an important factor in the Government's considerations.
Because the British motor industry cannot immediately move to that situation it is vital that the House gives it proper and adequate notice of the way in which we intend to move. It would be ludicrous if, at a time when continental countries—particularly Germany—and the United States are moving in the direction of lead-free petrol, or petrol containing only small quantities of lead, we failed to follow that example and inflicted injury upon the export prospects of car manufacturers. Here again, the economic interests coincide with the health interests. If we move, as I hope we shall, to this level by 1981 it will cost £70 million on the balance of payments, whereas if we moved to the final level immediately it would cost £170 million.
The subject of the Gravelly Hill report was raised, in particular by my hon. Friends the Members for Birmingham, Erdington (Mr. Silverman) and Birmingham, Perry Barr (Mr. Rooker). The working party which produced the report was established after a visit there by me at the invitation of my hon. Friend the Member for Birmingham, Erdington. There has been first-class co-operation between Aston University, Birmingham University, the City of Birmingham and my Department.
As it is public knowledge, I shall not weary the House with all the details of the findings of the working party, but I agree with my hon. Friend the Member for Sheffield, Heeley (Mr. Hooley) that the significance of its report is that it showed that the blood lead levels of children in urban and city environments exceeded those of children elsewhere. We intend to do much more research into these matters and the House will want us to keep this subject under constant review. The general range of lead levels in the blood of children tested in the Gravelly Hill and Birmingham areas was between 12 and 16 milligrammes per 100 millilitres, but there were occasional instances in which it reached nearly 35 milligrammes.
I have been asked many questions about filters and filter traps. I am advised that filter traps would not materially help us in the programmes that I have announced, but that if we move to levels below 0·40 grammes, filter traps may be of great benefit. However, the motor car industry itself has advised that it would require at least three years' notice of the installation of filter traps for its own purposes.
Filter traps are not the answer to this problem. I have already told the House that we are determined to keep the amount of lead emission from motor cars down to 1971 levels. It would take a long time to fit filter traps to existing motor cars, let alone fit them to new models. That being so, I can only say that, following our examination of the situation, we can keep within the 1971 levels only by taking lead out of petrol in progressively increasing quantities, as the directives propose.