Table 2 CAPs composition and ambient gaseous pollutants during 8-h exposure periods in Detroit and Grand Rapids

CAPs mass

μg/m³

542

519

Organic carbon

μg/m³

177

280

Elementary carbon

μg/m³

4

7

Sulfate

μg/m³

216

58

Nitrate

μg/m³

19

23

Ammonium

μg/m³

48

51

Mg

ng/mg³

580

770

Al

ng/mg³

762

608

Ca

ng/mg³

1557

2365

V

ng/mg³

22

6

Mn

ng/mg³

108

236

Fe

ng/mg³

2760

3410

Ni

ng/mg³

9

10

Cu

ng/mg³

64

228

Zn

ng/mg³

594

438

Se

ng/mg³

141

61

Rb

ng/mg³

3.4

4.2

Mo

ng/mg³

4.6

5.2

Cd

ng/mg³

2.3

1.9

Ba

ng/mg³

7.0

25.1

La

ng/mg³

2.0

1.1

Ce

ng/mg³

3.0

3.7

Pb

ng/mg³

107

49

Ambient gaseous pollutants

CO

ppm

0.6

1.2

SO₂

ppb

29

2

NO

ppb

9

14

NO₂

ppb

22

15