§ 93. Mr. John Hallasked the Secretary of State for Education and Science if the Medical Research Council's Air Pollution Research Unit has been able to estimate the amount of benzpyrene likely to be inhaled each day by residents of densely populated cities; and what study he has made of the conclusions of Professor F. C. Pybus, a copy of which has been sent him, in which it is pointed out that atmospheric pollution is a most serious cause of lung cancer and of cancer generally.
§ Mr. CroslandThe Unit has made estimates of the kind referred to in the Question; the most recent measurements show that an active person might inhale half-a-microgram of benzpyrene per day in the City of London. In residential areas of London and some provincial towns the amount might be twice as much. Only a small fraction of this, however, would be retained in the lung since the majority of smoke particles are exhaled.
I am advised that the main conclusions drawn by Professor Pybus are not supported by the evidence. Although air pollution may play a part in the production
322Wedition of my Department's List 69 (Secondary Education in each Local Education Authority Area), published annually by Her Majesty's Stationery Office.
of lung cancer, research to date has not provided evidence of a direct causal relationship.