In July Moscow air was most polluted

The state of Moscow's atmospheric air between May and July 2002 was gauged from 6,500 laboratory samples of the air taken by 48 travelling posts, RIA Novosti was told at the press-service of Moscow's State Sanitary and Epidemiological Service, or Gossanepidsluzhba.

Tests were carried out for the content of 12 pollutants in the air: nitrogen dioxide, carbon oxide, phenol and others. Analysis showed that most of the air pollutants did not have concentrations exceeding permissible hygienic norms (maximum permissible concentrations). On the other hand, carbon oxide, nitrogen dioxide, formaldehyde and hydrocarbons of the petrol faction exceeded the permissible concentration values. A contributing factor was unfavourable weather conditions when emitted noxious substances were accumulated in the lower layers of the atmosphere. Such periods were longest in July -- three to four days each.

Most of the negative samples were collected by posts situated close to busy motorways. The main carbon oxide polluter of the city air is motor transport, with exhaust gases contributing over 90 per cent of this impurity. It was also noted that air pollutant concentrations decreased with distance from the major superhighways.