Vol.1 part 4-5 - Department of Invertebrate Zoology

provided for a rather broad examination of tissue levels
of trace metals of biota from the entire study area but it
provided very limited data for any single organism .
More samples of fewer species would improve the reliability
of the data and information regarding possible
differences within the study area . Comparison of the values
with other areas of the Gulf Coast (STOCS and
MAFLA) for those organisms common to all three studies
shows no consistent elevations in the Louisiana study
area . The levels of the trace metals measured in biota
are well below those necessary to cause public health
concern .
E. Recommendations for Further Studies
Further development is needed of the data evaluation
technique of linear regression of sediment
trace metal concentrations with other chemical
and physical parameters . This technique is a
valuable tool in determining abnormal levels of
trace metals in the sediments and could be
expanded to investigate other chemical and physical
parameters that correlate with trace metal
concentrations . More intensive investigations into
the technique and its limitations are needed . Sufficient
data to further evaluate this technique already
exist from previous studies done in the Gulf
of Mexico and elsewhere .
2 . An in situ means of determining trace metal pollution
from a point source (e.g ., petroleum production
platforms) is needed to eliminate extraneous
factors that could prevent an accurate determination
of a pollution event or of long-term
chronic pollution .
Placing filter-feeding organisms (clams, oysters,
etc .) at a petroleum production platform (in non-contaminating
cages) and harvesting them 6 months to 1
year later would be one way of determining trace metal
pollution . A similar control group of filter-feeding organisms
would also be placed at a site such as an inactive
production platform, buoy, sunken ship, etc . The
trace metal concentrations in the soft tissues of the organisms
from the active platform site would be compared
to those from the control site ; this comparison would
provide data on the amount of trace metal pollution
coming from an active petroleum production platform .
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