damage to oyster larvae and developing English 

 sole eggs at concentrations greater than 10 mg/1 

 of 10-percent SWL. According to this report, 

 oyster growth and market condition is adversely 

 affected and phytoplankton productivity is in- 

 hibited at SWL concentrations over 50 mg/1. 



Determining the toxicity of complex wastes like 

 oil, refinery petrochemicals, and pulpmill wastes 

 presents a number of problems. For one thing, 

 they contain many known and, perhaps, equally 

 as many unknown toxic substances in small quan- 

 tities. The toxicological and other physical and 

 chemical characteristics can vary considerably dur- 

 ing any given day, in any given plant, due to 

 changes in processes, sources of supplies, and the 

 end product being produced. Considerable varia- 

 tion in effluent characteristics can occur even in a 

 1-day period. The resulting wastes from these in- 

 dustries contain upwards of several hundreds of 

 compounds representing a number of homologous 

 series of compounds from different organic groups. 

 This complexity is augmented by the treatment of 

 the wastes, as well as by the spectrum of products 

 manufactured from the complex starting material 

 used. The relative ability to react biochemicahy 

 and to exert an oxygen demand is characteristic of 

 organic materials of such primary significance. 



Many groups or series of compounds indicated 

 to be present in such wastes have been shown to 

 be toxic in varying degrees to aquatic life. It is 

 extremely difficult at this time, however, to place a 

 concentration limit or set threshold criteria for 

 such complex systems and hence should be indi- 

 vidually bioassayed and their discharge managed 

 accordingly. 



Waterfront and boating activities. — Increasing 

 activities by commercial, military, and recreational 

 vessel operators raise the specter of introduction of 

 toxic materials in quantities sufficient to affect 

 marine organisms adversely. This is particularly 

 likely in the case of confined waters of small tidal 

 tributaries, lagoons, embayments, and other ma- 

 rine areas employed as harbors. 



Toxic materials are used to prevent activities of 

 boring and fouling marine organisms. Usually, 

 however, every effort is bent in the case of toxic 

 coatings to prevent rapid release of toxic materials 

 into the environment since rapid loss reduces ef- 

 fectiveness of such coatings and increases costs. 

 Some leaching is unavoidable — even necessary. 

 Thus, the presence in confined harbors of many 

 vessels whose bottoms are coated with toxic mate- 

 rials already presents hazards in some places. This 

 would be especially true after spring "fitting out" 

 for small boats. 



Boatowners, boat and boatyard operators, fish- 



ing and commercial pier and marina operators are 

 not especially noted for the care extended to 

 nearby waters. Commonly, everything that can be 

 is flushed or jettisoned into the water. Purposeful 

 discharges are many — though perhaps decreasing 

 as emphasis on water pollution has increased. 

 Paint leaching, paint spillage, oil and gasoline 

 spillage, detergents, wood preservatives, ex- 

 hausted containers, metallic objects of all types 

 (zinc, copper, brass, iron, etc.), and other jetsam 

 contribute to contamination from these sources. 



Except for confined areas where there are many 

 of these operations such as large shipyards, major 

 military and commercial anchorages, and large 

 and small boat anchorages, it is doubtful that tox- 

 icity from these operations is of serious proportions 

 in tidal waters at this point. As with other fouling 

 or contaminating activities of society, however, 

 efforts should be made to keep biological damage 

 from these sources to a minimum. Some discharges 

 are controllable and should fall under the same 

 rules as industrial or community discharges. In the 

 case of large marinas, shipyards, or major anchor- 

 ages, requirements suggested elsewhere may have 

 to be applied. Future research should include spe- 

 cific attention to this aspect. 



Similar comments can be made about water- 

 front structures and port operations. There is con- 

 siderable use of toxic materials in preservation of 

 wood, steel, and masonry structures used on ma- 

 rine waterfronts. Discharge of toxic materials, 

 surfactants, petroleum products, other materials 

 and jetsam is common. Similar recommendations 

 can be made for control and research as those for 

 boat, boatyard, and vessel operations. 



Disposal of laboratory wastes. — The rapid 

 growth of marine sciences during the past decade 

 is reflected in an ever-increasing number of sta- 

 tions and laboratories engaged in the study of 

 various aspects of oceanography. These institu- 

 tions are located along the entire coastline of the 

 United States: 28 on the Atlantic, 12 on the Gulf, 

 and 29 on the Pacific. About 2,500 persons (in- 

 vestigators, students, technicians, and laboratory 

 assistants) are employed in these 66 establish- 

 ments (Hiatt, 1963). 



The above number includes institutions operated 

 by Federal and State governments, by universities 

 or privately endowed concerns which receive their 

 main support from the government and national 

 foundations. Other laboratories, hospitals, and re- 

 search institutions operated by industrial concerns 

 for their specific needs are not included in this 

 total. The laboratories range from small establish- 

 ments, with less than four investigators, to very 

 large institutions employing or providing research 

 space for 200 to 500 investigators. 



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