Fig. 1From: Asthma and COPD exacerbation in relation to outdoor air pollution in the metropolitan area of Berlin, Germanyavailable at all five stations, PM at stations 1, 3, and 4, O3 at stations 1 and 3City of Berlin boundaries (black line) with Charité campuses (red squares), meteorological station (green dot), and urban background air quality monitoring stations (blue numbers). NO2 data was Back to article page