70 55 
Lead Distribution 
X background 
value 
fiq/q 
0 0-50 
!!!!l!l! 50-100 
HHi 100-150 
Hi 150-200 
■H >200 
0-5 X 
5-IOX 
I0-I5X 
15-20 X 
>200 X 
BOSTON HARBOR 
0 2 4 
05 
00 
Figure 5. Lead Distribution in Boston Harbor Sediments. Data Contoured by Hand 
Using Data Compiled of Fitzgerald (1980) and White (1972). Background 
Sediment Concentrations are Based on Average Value of Four Massachusetts 
Sediment Samples. See White (1972) for Details. 
44 
