Biological effects of exposure to lead in ambient air among Tokyo inhabitants.

Abstract

The purpose of this study was to examine whether the health of Tokyo inhabitants was affected by lead in the ambient air, on the bases of place of residence, age and sex. The study came about as a direct result of public concern over a press report that people living near busy traffic intersections were being poisoned by lead in the air. In 1970 and 1971, the laboratories of the Tokyo Metropolitan Institute of Health and the Occupational Health Service Center performed laboratory tests on inhabitants who were concerned about air pollution and presented themselves to their local health departments. The results were then passed on to the Keio University School of Medicine for evaluation.The average lead levels in blood and urine were slightly higher in those person living in houses which faced a main street (13.3 μg/100ml blood) than in those who living on side streets (12.8 μg/100ml). However, there was no association found to exist according to the distance of the house from the main street. Blood lead levels were higher in males (15.0 μg/100ml) than in females (11.2 μg/100 ml). Lead levels in urine were also higher in males than in females: 13.1 μg/100 ml as opposed to 11.7 μg/100ml. There was no particular association between age and lead levels in blood or urine.The average lead levels in blood and urine differed by district but showed no systematic pattern or relationship to the population density. This seems to be due to technical differences between the two laboratories responsible for the testing as well as to the difficulty in determining such small amounts of lead in blood and urine.In conclusion, according to the available techniques, there was no evidence of an increased level of lead in blood or urine as a result of lead in the ambient air of Tokyo. The results obtained in this study agree with a previous report by the present authors' and with a report by Tepper and Levin2 from the U.S.A.