Table 2.
Distribution of PM, NO 2 and traffic exposure in rural and in urban areas
| |
Total area (N = 402) |
Rural area (N = 190) |
Urban area (N = 212) |
p-Value
e
|
|---|---|---|---|---|
| Variable | Median (IQR) | Median (IQR) | Median (IQR) | |
|
Nearest monitoring stations (Five-year mean)
a
|
|
|
|
|
| NO2 [μg/m3] |
30.8 (13.2) |
20.2 (0) |
33.4 (2.6) |
< 0.0001 |
| PM10 [μg/m3] |
25.3 (3) |
25.2 (0) |
28.2 (3.4) |
< 0.0001 |
|
LUR-modelled exposure
b
|
|
|
|
|
| NO2 [μg/m3] |
26.0 (9.42) |
23.0 (2) |
31.9 (10.3) |
< 0.0001 |
| PM10 [μg/m3] |
26.4 (2.26) |
25.6 (0.89) |
27.7 (2.7) |
< 0.0001 |
| PM2.5 [μg/m3] |
17.4 (2.06) |
17.0 (0.42) |
18.9 (1.7) |
< 0.0001 |
| PM2.5 absorbance [10−5 m−1] |
1.38 (0.44) |
1.20 (0.13) |
1.62 (0.47) |
< 0.0001 |
| Traffic loadc [vehicle*km/day] |
0 (990) |
0 (0) |
0 (1330) |
0.0003 |
| |
% |
% |
% |
|
| Distance < 100 md | 19.1 | 14.7 | 23.1 | 0.0331 f |
aFive-year mean of 2003 – 2007 from the nearest monitoring station of the State Environment Agency covering the area in an 8-km grid (1 station in Borken, 5 stations in Ruhr-Area).
bLand-use regression modelled exposure using data from a measurement campaign (2008/2009) gained in the framework of the EU-ESCAPE study for assessment of individual long-term exposure (Modelling based on the measurements from 40 stations for NO2 and 20 stations for PM).
cTraffic volume within a 100 m buffer around the home, calculated as the sum of the products of the number of vehicles from all roads with ≥ 5,000 vehicles per day multiplied with the street section length in the 100 m buffer.
dDistance of residential address < 100 m from major road with more than 10,000 vehicles per day.
ep-Value of Wilcoxon test for the difference of means between rural and urban area.
fp-Value of χ2-test for the difference between rural and urban area.