Metals
29
6 0 , 0 0 0 - . - - - - - - - - - - - . . . - - - - - - - - - - - - - - - - - - - - ,
55,000 1 AI ,,/'\
50,000 V"-J
45,000
\
40,000
"
i 35,000
c:
o
~ 30,000
"E
~
5 25,000
u
20,000
/\
j\
15,000
a
a_a
10,000
5,000
a-a/\a~\
f~-~~AJ~~_~I
o
A B D E F G H
J K L M N O P Q R S T UVWXZ
Sample location
Table 2.14
Mean background concentration of heavy metals in the sediments of the Rideau River
using different extraction methods (from [37])
mgkg- 1
4.0N HN0 3
1 N NHzOH . HCl
Metal Total a
+ 0.7 N HCl
0.5 N HCl
+ 25 % acetic acid
0.05 N EDTA
Cd
0,3
0,4
0,2
Cu
42
13
11
2
8
Pb
84
24
17
16
16
Zn
94
67
36
20
16
Ni
72
23
8
3
3
Cr
108
37
7
2
Co
57
17
6
2
4
Mn
582
451
305
304
275
Fe
31000
30000
6700
3000
2600
AI
46200
15000
3930
1150
620
a HF - HN0 3 - HCl0 4 with PTFE bomb decomposition