Substantial decreases in air pollution levels following German reunification appear to have translated into improved respiratory health for children in East Germany.
The improvements have resulted from chemical and power plant closings, combined with conversion from brown coal to gas heat in many dwellings. Since previous studies have examined links between increases in respiratory illness and rising air pollution, researchers from the GSF–Institute of Epidemiology in Oberschleissheim attempted to determine whether decreased pollution could lead to improvements in respiratory symptoms.
Voelker R. Breathing Easier. JAMA. 2000;284(2):169. doi:10.1001/jama.284.2.169-JWM00005-2-1