In a group of 8-12-year-old children from two areas of Bratislava with a different degree of air pollution the authors investigated repeatedly the growth of the children. It was revealed that in boys and girls from the exposed area growth was retarded, as compared with children from a relatively clean area as well as when compared with the Bratislava population. After improvement of the living environment in the exposed area children who grew up in an environment, where the two areas did not differ as to contamination of the atmosphere, achieved the same growth level at the age of 10 years. The results draw attention to the importance of care of the living environment and of attempts to eliminate noxious substances from the atmosphere which is reflected in a better health status and development of the child organism.