Table 1

Descriptive characteristics of hospital admissions counts, traffic-related pollutants and meteorological variables in London, UK for 2011–2012

Number of daysMeanMedianIQR (75th–25th centile)90th Centile
Hospital admissions
Cardiovascular (years)
Respiratory (years)
Pollutants (μg/m3; CO in mg/m3)
General traffic indicator
 NOx urban increment70342.530.833.184.4
Petrol vehicle exhaust
 CO urban increment7240.
Diesel vehicle exhaust
 EC (in PM10)6821.
 EC urban (in PM10)5900.
 BC (in PM2.5)7021.51.212.8
 BC urban (in PM2.5)6290.
Vehicle non-exhaust
 Cu (in PM10)6770.00930.00720.00750.0176
 Zn (in PM10)6770.0120.00870.00910.0246
 Al (in PM10)6770.0760.05550.06050.1528
Regulated pollutants (μg/m3)
Meteorological parameters
 Mean temperature (°C)73111.7011.707.518.10
 Relative humidity (%)73176.4378.0014.688.50
  • PM, particulate matter; PM2.5, particles with aerodynamic diameter <2.5 μm; PM10, particles with aerodynamic diameter <10 μm.