Table 2.

Levels of the different environmental exposures of the eligible participants from the Swiss National Cohort at baseline (2001).

Exposure	Mean (SD)
Road traffic noise [Lden (dB)]	54.4 (8.2)
Railway noise [Lden (dB)]	38.6 (11.1)
Aircraft noise [Lden (dB)]	34.5 (7.8)
${\mathrm{PM}}_{2.5}$ concentration ($\mathrm{\mu }\mathrm{g}/{\mathrm{m}}^3$) [mean (SD)]	15.9 (2.4)
${\mathrm{NO}}_2$ concentration ($\mathrm{\mu }\mathrm{g}/{\mathrm{m}}^3$) [mean (SD)]	23.7 (7.5)
NDVI exposure (no unit) [mean (SD)]	0.57 (0.11)

Note: dB, decibel; ICD, International Statistical Classification of Diseases and Related Health Problems, 10th Revision; Lden, day-evening-night level; NDVI, normalized difference vegetation index; SD, standard deviation.