In June 2026, the Binningen monitoring station recorded zero days with a KBI of 1, indicating no days with low air pollution. There were 17 days with a KBI of 2, representing moderate pollution. More significantly, there were two days with a KBI of 3, indicating marked pollution, and seven days with a KBI of 4, indicating significant pollution. No days reached a KBI of 5 or 6. The KBI, or Kurzzeit-Belastungs-Index, is a short-term exposure index that combines the concentrations of ozone, nitrogen dioxide, and particulate matter into a single value to assess overall air quality. The mean concentration for ozone was 77.6 µg/m³, with a maximum of 175.8 µg/m³. For nitrogen dioxide, the mean was 6.1 µg/m³ and the maximum was 31.4 µg/m³. For particulate matter, the mean was 13.7 µg/m³ and the maximum was 41.6 µg/m³. All values are listed in Table 1, and regulatory thresholds are listed in Table 3.

Compared to previous years, June 2026 shows a mixed picture. For days with a KBI of 1, the month ranked 6th out of 9 years, meaning it had fewer such days than most other years. For days with a KBI of 2, it also ranked 6th. In terms of maximum pollutant concentrations, June 2026 ranked 2nd for maximum ozone, indicating a relatively high peak value. It ranked 8th for maximum nitrogen dioxide and 4th for maximum particulate matter. The monthly average and maximum values for June are reported in Table 2 and also displayed in Figures 1 to 3.