In a concentration of 0.5 percent, the embryos sur- 

 vived for 13 days (end of test); in 1.25 percent, 

 8i days; in 2.5 percent, 6 days; and in 5 percent, 

 4i days. Barnacles suffered 80 to 90-percent 

 mortality within 70 hours in 2.0-percent mixtures 

 of oil in sea water. They became inactive in 23 

 hours in concentrations of 2 percent and above. 

 Tubularia suffered 90 to 100-percent mortality 

 within 24 hours after being placed in water con- 

 taining a 1:200 oil-carbonized sand aggregate. 

 Water extracts of crude oil were lethal within 24 

 hours at concentrations of 500 mg/1 and greater. 



Experiments with oysters consisted primarily of 

 determining the effect of oil adsorbed on carbon- 

 ized sand on the number of hours the oysters re- 

 main open and feeding and on the rate of water 

 transport, across the gills. A paste-like aggregate of 

 oil in carbonized sand (50 ml crude oil to 127 g 

 sand) was prepared, wiped clean of excess oil, and 

 placed in the mixing chamber. Sea water was de- 

 livered through this chamber to the recording ap- 

 paratus at a rate slightly in excess of the rate of 

 water transport by oyster gills (Galtsoff, 1964; 

 Chipman and Galtsoff, 1949). There was a notice- 

 able decrease in the number of hours the test 

 oysters remained open and in the daily water trans- 

 port rate through the gills. The time open was re- 

 duced from 95 to 100 percent during the first 4 

 days of testing to only 19.8 percent on the 14th 

 day. The total amount of water transported per 

 day, and presumably used for feeding and respira- 

 tion, was reduced from 207 to 3 10 liters during the 

 first 6 days to only 2.9 to 1 liter per day during 

 the period between the eighth and 14th day of 

 continuous testing. These tests indicate that oil 

 incorporated into the sediments near oyster beds 

 continues to leach water-soluble substances which 

 depress the normal functions of the mollusk. 



Critical observations are lacking on the effect of 

 oil on pelagic larvae of marine invertebrates, but 

 there is good reason to assume that crude oil and 

 petroleum products are highly toxic to free-swim- 

 ming larvae of oysters. Speer (1928) considers 

 that they are killed by contact with surface oil film. 

 Laboratory experience of Galtsoff (impublished 

 records) shows that oyster larvae from 5 to 6 days 

 old were killed when minor quantities of fuel oil 

 were spilled by ships in the Woods Hole harbor 

 and the contaminated water penetrated into the 

 laboratory sea water supply. 



The tests described above leave no doubt that 

 water-soluble substances are leached from oil 

 spilled into water and adversely affect marine life. 

 It is reasonable to assume that the water soluble 

 materials of oil may contain various hydrocarbons, 

 phenols, sulfides, and other substances toxic to 



aquatic life. The water-soluble fraction leached 

 from crude oil is easily oxidized by aeration and 

 loses its toxicity (Chipman and Galtsoff, 1949). 



Carcinogenic Substances From 

 Oil-Polluted Waters 



Presence of hydrocarbons similar to benzo- 

 pyrene in oil-polluted coastal waters and sediments 

 of France in the Mediterranean was reported by 

 Mallet (1965) and Mallet and Sardou (1965). 

 The effluents from the industrial establishments on 

 the shores at Villefranche Bay comprise tar sub- 

 stances, which contain benzopyrenes, benzo-8, 

 9-fluoranthene, dibenzanthracenes, chrysene, 10- 

 methyl anthracene, and nitrogenous derivatives 

 such as dimethylbenzacridine. These substances 

 are carried out into the bay water and settle on the 

 bottom. The pollution is augmented by incom- 

 pletely burned oils discharged by turbine ships. 

 The content of benzopyrene in bottom sediments 

 ranges from 500 micrograms in 100 g sample col- 

 lected at the depth of 8 to 13 cm to 1.6 micro- 

 grams at 200 cm. Similar contamination is of im- 

 portance in the Gulf of Fos, Etang de Berne, and 

 in the delta of the Rhone River. 



Carcinogenic hydrocarbons were foimd to be 

 stored in plankton of the bay of Villefranche, in 

 concentrations varying from 2.5 to 40 micrograms 

 per 100 g. Fixation of benzopyrenes was found 

 also in the bodies of holothurians (Lalou, 1965) 

 in a bay near Antibes. The reported concentration 

 in the visceral mass of holothurian was slightiy 

 higher than that in the bottom sediment. 



Observations on storage of carcinogenic com- 

 pounds found in oil-polluted water are biologically 

 significant. The important question of biological 

 magnification as these compounds are ingested by 

 plankton feeders remains unanswered and needs 

 to be investigated. 



Sampling of Oil-Polluted Sea Water 



The question of the minimal concentration of oil 

 and petroleum products consistent with unin- 

 hibited growth and reproduction of aquatic species 

 is more difficult to answer than it is in the case of 

 other contaminants. As has been shown above, oil 

 is found in water in four distinct phases: (1) sur- 

 face oil film, (2) emulsion in sea water, (3) ex- 

 tract of water soluble substances, and (4) semi- 

 solid aggregate of oil and sediment covering the 

 bottom. Obviously, no single sample could include 

 all four phases and the method of sampling should 



73 



