[Susceptible populations and urban atmospheric pollution. Development of a policy of protection].

The short term vulnerability of sections of the population to the harmful effects of chemical pollutants in the urban atmosphere represents an important unresolved problem of public health. These groups include young children, the elderly, asthmatic patients, and patients with chronic bronchitis and cardio-respiratory insufficiency. A recently ratified French law on air and rational energy use is aimed at resolving this problem in the context of recognizing that everybody has a right to breathe air which is not damaging to their health. In order to achieve this objective and direct the measures to be taken to reduce the emission of pollutants relating to industrial activity, to heating and to road traffic, the law provides for an extension to the chain of automatic registering stations which enable the recording of atmospheric data in large urban centers. It also defines the limits of substances allowed in the air over given periods and revises the critical levels of particulate and gaseous pollutants allowed according to current experimental and epidemiological data. Thresholds for information and for alerting the population will also be defined, with eventually restrictive measures for industry and for car traffic envisaged. These provisions are a major step for the protection of susceptible populations and should be enhanced in the near future by extension to cover other potentially noxious substances. This requires continued study on the short and long term effects of atmospheric pollution on people's health.