Element

Concentrations of particulate per sample (wt%)

Bus

Truck

S

52.67

30.08

Fe

16.51

22.24

Si

11.83

7.63

Ca

9.00

23.82

Zn

2.95

12.10

P

1.85

2.11

Ni

1.37

0.29

Cr

0.69

0.56

Ti

0.62

0.44

Mn

0.31

0.49

Cu

0.18

0.24