69 
from major drainage systems. For example, a recent study 9/ revealed 
that about 1300 pounds of pesticides (DDT metabolites and dieldrin) 
entered equatorial Atlantic waters from the atmosphere, as compared 
to the 4300 pounds that have been calculated to enter San Francisco 
Bay annually, or the estimated 225,000 pounds that annually empty 
into the Gulf of Mexico from the Mississippi River. Possibly a 
significantly greater proportion of pollutants from land drainage 
become bound in coastal bottom sediments than pollutants which enter 
marine environments directly from the atmosphere. Thus, contribu- 
tion from at least some atmospheric contaminants in a given area 
may be comparable to their contribution from the land. 
The amount of waste materials deliberately released into the 
ocean annually in the next decade is expected to be significantly 
greater than what was dumped in 1968 (see Appendix 3). Increas- 
ingly stringent regulations as they relate to air and water pol- 
lution make sea disposal more and more attractive to cities and 
industries. The scarcity of available land for disposal sites, 
adds further incentive for looking to the sea as an easy and rela- 
tively inexpensive solution. That the ocean environment will be 
further affected no one can deny. The uncertainty is only in the 
magnitude and nature of the effects and their long-term consequences. 
The assimilative capacity of the ocean is great but it is 
becoming apparent that the mechanisms of these assimilative proc- 
esses are being threatened. Coastal environments have a limited 
capacity to receive wastes, a capacity that has already been 
exceeded in many areas. Gradually we are beginning to recognize 
the awesome and terrible consequences of biological amplification 
of DDT and other biologically active hydrocarbons, heavy metals, 
radioisotopes, and other industrial wastes. Many of these substances 
already occur in substantially greater concentrations in the upper 
layer of the ocean than in the total ocean. Thus, calculations of 
the capacity of the ocean to assimilate wastes need to consider the 
infinitely slow mixing process between the upper and deeper layers. 
The fate of pathogenic organisms in marine waters has not been 
studied extensively, though their pessible routes are identifiable 
and include water movement as well as concentration and retention 
_in food organisms. For example, laboratory studies have shown 
that oysters can accumulate polio virus to at least 60 times ambi- 
“ent concentrations in water. Experimental evidence shows further 
that water is a very poor indicator of viral concentrations, that 
the coliform counts. in water and oysters are inadequate indicators 
=) Riseborough, R. W., et al., SCIENCE V 159 3820, March 15, 1968, 
pp. 1233-35, “Pesticides Trans-Atlantic Movement in the Northeast 
Trade." 
46 
