4 Isotope Geochemistry in the Environment
59
1.20
1.10
1.00
1/,
13
Russia (Altai)
6
5~\ ,~ o41~o_.,' ~' ,
,,v
3 -..j,// .~ t " ~
1
~ - ~ . J"~"
AustraLia (ThT)
AustraLia (BHT)
l
l
i
I
I
I
I
I
I
I
|
I
I
I
1
l
J
t
2.30
2.35
2.40
2.45
~~ / Z~
Fig. 4.9. Anthropogenic lead contamination in Munich (Germany) shown using
2~ Pb/--'~ Pb and --'~ pb/2~ Pb ratios. 1: sewage works; 2: petrol lead (1985-87); 3: air filter:
4: beer; 5: blood; 6: tap water; 7-9: older sewage works; I0: soil; I1: triassic Pb-Zn
deposits; 12: carbon coal; 13: sediments of Isar river in Mumch; 14: limestones of the
Munich area: 15: sewage work deposits from 1976. (Horn et al. 1987)
An additional isotope study that may be of interest here was able to demonstrate
anthropogenic lead contamination and the origin of this lead in a large European
city (Munich, Germany; Horn et al. 1987). In this study, not only were Pb isotope
analyses carried out on water, sediment and soil samples, but also on petrol,
blood, beer and other materials such as air filter dust and coal. It is striking in the
-'~176
vs. z~176
diagram (Fig. 4.9) that almost all components go
towards defining a mixing line, with carbon-coal on one side and petrol lead on
the other defining the end members. The coal shows enhanced 2~176
and
_,o.,~pb/207pb isotopic ratios, while petrol lead used between 1985 and 1987 shows
low lead isotope compositions. Lead in petrol which is an anti-knocking agent
(lead tetramethyl) derives from two Australian localities, Broken-Hill and
Thakaringa in the proportion 60:40.
The isotopic composition of the lead from the air filter can be looked at as a
product of the mixing of lead from coal and petrol lead. This ought to be at least
close to the truth as the air filter was located near a coal-heated power station. The
isotopic ratio of blood lead lies likewise on the same mixing line : petrol lead - air
filter - coal lead. From the isotope data it is easy to estimate that about 35% of the
whole blood lead content comes from petrol. Beer lead shows somewhat lower
lead isotopic ratios but lies close to blood lead. The proportion of petrol lead in
beer lies around 40%. This relatively high amount is not surprising when we
59
1.20
1.10
1.00
1/,
13
Russia (Altai)
6
5~\ ,~ o41~o_.,' ~' ,
,,v
3 -..j,// .~ t " ~
1
~ - ~ . J"~"
AustraLia (ThT)
AustraLia (BHT)
l
l
i
I
I
I
I
I
I
I
|
I
I
I
1
l
J
t
2.30
2.35
2.40
2.45
~~ / Z~
Fig. 4.9. Anthropogenic lead contamination in Munich (Germany) shown using
2~ Pb/--'~ Pb and --'~ pb/2~ Pb ratios. 1: sewage works; 2: petrol lead (1985-87); 3: air filter:
4: beer; 5: blood; 6: tap water; 7-9: older sewage works; I0: soil; I1: triassic Pb-Zn
deposits; 12: carbon coal; 13: sediments of Isar river in Mumch; 14: limestones of the
Munich area: 15: sewage work deposits from 1976. (Horn et al. 1987)
An additional isotope study that may be of interest here was able to demonstrate
anthropogenic lead contamination and the origin of this lead in a large European
city (Munich, Germany; Horn et al. 1987). In this study, not only were Pb isotope
analyses carried out on water, sediment and soil samples, but also on petrol,
blood, beer and other materials such as air filter dust and coal. It is striking in the
-'~176
vs. z~176
diagram (Fig. 4.9) that almost all components go
towards defining a mixing line, with carbon-coal on one side and petrol lead on
the other defining the end members. The coal shows enhanced 2~176
and
_,o.,~pb/207pb isotopic ratios, while petrol lead used between 1985 and 1987 shows
low lead isotope compositions. Lead in petrol which is an anti-knocking agent
(lead tetramethyl) derives from two Australian localities, Broken-Hill and
Thakaringa in the proportion 60:40.
The isotopic composition of the lead from the air filter can be looked at as a
product of the mixing of lead from coal and petrol lead. This ought to be at least
close to the truth as the air filter was located near a coal-heated power station. The
isotopic ratio of blood lead lies likewise on the same mixing line : petrol lead - air
filter - coal lead. From the isotope data it is easy to estimate that about 35% of the
whole blood lead content comes from petrol. Beer lead shows somewhat lower
lead isotopic ratios but lies close to blood lead. The proportion of petrol lead in
beer lies around 40%. This relatively high amount is not surprising when we