TABLE III-3. Concentration of Phenolic Com- 

 pounds That Cause Tainting of Fish Flesh 



After Bandt (1955) page 77 (except for phenol). 



Concentration 

 affecting taste 

 and odor (mg/l) 



Fish tested 



Pure compounds: 



Phenol 15 to 25 Trout, carp, tench, 



chub, eel, min- 

 now, perch, blue- 

 gill, pike, gold- 

 fish. 



Cresols 10 Tench, carp, eel, 



trout, minnow. 



Xylenols 1 to 5 Roach, perch, carp. 



Pyrocatechol 2 to 5 Perch, carp, roach. 



Pyrogallol 20 to 30 Roach, carp. 



P-Quinone 0.5 Carp, tench, roach. 



Pyridine 5 Roach, carp. 



Naphthalene 1 Roach. 



Alpha NaphthoL_0.5 Roach, carp. 



Quinoline 0.5 to 1.0 do. 



Chlorophenol __-0.1 



Mixed phenolic wastes: 



Coal-coking 



wastes 0.02 to 0.1 Freshwater fish. 



Coal-tar wastes__0.1 do. 



Phenols in 



polluted river_-0.02 to 0.15__- Minnows. 



Sewage contain- 

 ing phenols ..0.1 Freshwater fish. 



A preliminary laboratory study (English, Mc- 

 Dermott, and Henderson, 1963) shows that out- 

 board motor exhaust damages the quality of water 

 in several ways, the most noticeable of which is 

 causing unpleasant taste and odor in the water and 

 off-flavoring of fish flesh. A later field study, Eng- 

 lish et al. (1963a, b) and Surber et al. (1965) 

 determined the threshold level of tainting of fish in 

 pond and lake waters to be about 2.6 gal/acre-foot 

 of fuel, accumulating over a 2-month period. The 

 gasoline used was regular grade and the lubricating 

 oil ( 1/2 pint/gal) was a popular brand of packaged 

 outboard motor oil. 



Recommendation: Materials that impart odor or taste 

 to fish flesh or other freshwater edible products such as 

 crayfish, clams, prawns, etc., should not be allowed to 

 enter receiving waters at levels that produce tainting. 

 Where it seems probable that a discharge may result in 

 tainting of edible aquatic products, bioassays and taste 

 panels are suggested for determining whether tainting 

 is likely. 



Radioactive materials in fresh 

 and marine waters 



Ionizing radiation, when absorbed in living 

 tissue in quantities substantially above that of nat- 

 ural background, is recognized as injurious. It is 

 necessary, therefore, to prevent excessive levels of 



radiation from reaching any organism we wish to 

 preserve, be it human, fish, or invertebrate. Beyond 

 the obvious fact that they emit ionizing radia- 

 tion, radioactive wastes are similar in many re- 

 spects to other chemical wastes. Man's senses can- 

 not detect radiation unless it is present in massive 

 amounts. Radiation can be detected, however, by 

 means of electronic instruments and quantities 

 present at very low levels in the environment can 

 be measured with remarkable accuracy. Because 

 of the potential danger, the disposal of radioactive 

 materials has been well planned and controlled. 

 Injuries and loss of life from disposal of radioactive 

 materials or from accidents involving these mate- 

 rials have been minimal. Four factors have con- 

 tributed to this safety record: (1) scientists and 

 legislators were aware of the dangers associated 

 with the release of radioactive materials into the 

 environment prior to the need for disposal; (2) re- 

 search has progressed to protect man against ra- 

 diation effects and levels of radiation that could be 

 released; (3) as knowledge of nuclear energy in- 

 creased, standards were developed for handling, 

 shipping, and disposing of radioactive substances; 

 and (4) an extensive monitoring program was in- 

 augurated and has been functioning for years. 



Upon introduction into an aquatic environment, 

 radioactive wastes can: (1) remain in solution 

 or in suspension, (2) precipitate and settle to 

 the bottom, or ( 3 ) be taken up by plants and ani- 

 mals. Immediately upon introduction of radioac- 

 tive materials into the water, certain factors inter- 

 act to dilute and disperse these materials, while 

 simultaneously other factors tend to concentrate 

 the radioactivity. Among those factors that dilute 

 and disperse radioactivity are currents, turbulent 

 diffusion, isotopic dilution, and biological trans- 

 port. Radioactivity is concentrated biologically by 

 uptake directly from the water and passage 

 through food webs, chemically and physically by 

 adsorption, ion exchange, coprecipitation, floccula- 

 tion, and sedimentation. 



Radioactive wastes in the aquatic environment 

 may be cycled through water, sediment, and the 

 biota. Each radionuclide tends to take a charac- 

 teristic route and has its own rate of movement 

 from component to component prior to coming to 

 rest in a temporary reservoir, one of the three 

 components of the ecosystem. Isotopes can move 

 from the water to the sediments or to the biota. In 

 effect, the sediments and biota compete for the 

 isotopes in the water. Even though in some in- 

 stances sediments are initially successful in remov- 

 ing large quantities of radionuclides from the 

 water, and thus preventing their immediate uptake 

 by the biota, this sediment-associated radioactivity 



49 



