[The direct health effects of air pollution in Vratsa in 1991].

The effect of air pollution in the town of Vratsa on the daily morbidity of the population has been studied during the first half of 1991. Studies are performed on the correlation between the daily dynamics in the pollution according to specific for the town indices ammonia, hydrogen sulfide, sulphur dioxide, nitric oxides, dust, meteorological parameters temperature of the air, relative humidity, air velocity, barometric pressure and some respiratory and allergic diseases among the population. It is already established that the level of the air pollution in the town of Vratsa, among which dominate ammonia and hydrogen sulfide, have a direct effect on the acute respiratory morbidity, more expressed among the children. This influence is traced both in episodes of increased pollution, and in the course of several days afterwards and is conductive by the combination of unfavourable meteorological conditions, hindering the dispersion of the atmospheric pollutants.