some of the chemical characteristics o£ the sediments. More recently, 

 detailed chemical and biological surveys of the area were undertaken 

 (Mackay, et al, 1972). 



Since summer 1971, increased sampling over a wide area has provided 

 a clearer understanding of the factors controlling the distribution and 

 dispersion of trace substances and a determination of their effect on 

 the fauna of the area. Organochlorine pesticides and polychlorinated 

 biphenyls, known to occur in sewage sludge, are presently being studied 

 by the University of Glasgow. 



As in the New York Bight, completed investigations of the dumping 

 grounds of the Firth of Clyde found a strong association of heavy metals 

 with organically rich sediments. Also, animals taken near the center of 

 the dumping area were found to contain much higher levels of trace ele- 

 ments than those taken further away. No sampling station was devoid of 

 fauna, though species composition varied considerably. For example, a 

 change was observed, from a molluskan/echinoderm community further from 

 the center of the dump to a polychaete community near the center. 



A study of the effects of sludge dumping in the outer Thames Estuary, 

 England (Shelton, 1971), determined that oxygen content of the bottom 

 waters was near saturation. Lower oxygen concentrations were observed in 

 surface waters. No apparent changes in benthic infaunal populations 

 were observed. 



b. Turkey . Large quantities of untreated sewage and industrial 

 wastes are discharged annually into the Bosphorus, Sea of Marmara and 

 Dardanelles from Istanbul and other municipalities in Turkey. 



This area was studied by Woodward-Envicon, Inc. , an environmental 

 consulting firm of San Diego, California, under the sponsorship of the 

 Turkish government, the City of Istanbul and the World Health Organization 

 (Marine Pollution Bulletin, 1972). 



The study determined that such discharges contributed 200-1,000 

 milligrams per liter suspended solids, had a biological oxygen demand of 

 150-400 milligrams per liter, resulted in pH of 7.1-8.4, and contained 

 from 5 X 10^ to 5 x 10^ coliform bacteria per 100 milliliters. Analyses 

 of samples taken from 22 bathing beaches by the Istanbul Public Health 

 Institute showed that seven of the beaches are highly polluted, and that 

 there is a high risk of typhoid, hepatitis, bacillary dysentery and gastro- 

 enteritis from such high concentrations of bacteria. 



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