The point is that it is precisely in the urban areas that the danger arises. It is there that the concentration of lead is most serious. With the number of motor vehicles in the Soviet Union in the 1950s, or even today, the danger in the non-urban areas would not be great. Surveys taken in America and Birmingham show a high level of lead in the atmosphere in urban areas, especially in areas where there is a heavy traffic flow. This is true of an area in my constituency called Gravelly Hill interchange which we call Spaghetti Junction.
Tests carried out at Gravelly Hill interchange by the joint working party initiated by my right hon. Friend the Minister of State show that over several years there was a significant increase in the lead content in the blood of people living in that area. Most people would agree that airborne lead is not the greatest source of lead poisoning. Lead paint, lead taken internally and factories operating processes involving lead constitute greater risks. The point is that this is an additional source, cumulative with the others. After examining the figures for Gravelly Hill, there can be little question that there has been an increase in the blood-lead content of statistical significance.