§ Mr. Atkinson
asked the Secretary of State for Transport what is the estimated weight of tetraethyl lead which is discharged into the atmosphere per hour as a result of 1,000 motor cars per hour travelling slowly along a 100-yard section of a four-lane roadway; and what is the estimated effect following the change in the regulations on 30th November 1976 reducing the lead content in petrol.
§ Mr. Horam
It is estimated that the imposition of the new limit of 0.50 grammes per litre would result in a reduction from about 3.3 to 3.0 grammes in the total weight of lead emitted in the situation described. A further reduction could be expected with the introduction of the lower limit of 0.45 grammes per litre on 1st January 1978.