182 U. S. BUREAU or FISHERIES 



study of the fluorine content of various fishery products and the effect 

 of this fluorine, as it naturaUy occurs in some fishery products, in the 

 metaboUsm of the animal organism. A series of so-caUed "balance" 

 experiments were started, in our College Park laboratories, to deter- 

 mine the intake and excretion of fluorine in rats fed a diet of canned 

 fish, containing about 8 parts per million of fluorine. Preliminary 

 work on this problem indicates that there were no apparent toxic 

 symptoms in the experimental animals after a test period of 12 

 weeks, and the consumption of fish was very statisfactory. 



MANUFACTURE OF FISHERY BYPRODUCTS 



The utilization of waste for the manufacture of byproducts is becom- 

 ing of increasing importance, probably more so in the fishery industries, 

 than in other food industries. It has been estimated that the value of 

 fishery byproducts represents about 15 percent of the total value of all 

 fishery products in the United States, When we study the diversifi- 

 cation of these byproducts and their uses, they loom into even greater 

 economic importance than their relative volume would seem to indi- 

 cate. Fishery byproducts furnish raw materials or finished products 

 for such highly important consuming industries as the drug, paint and 

 varnish, soap, and feed industries. Accordingly, our technologists are 

 giving increasing attention to the conversion of fish waste and other 

 waste materials resulting from our fishery harvest into useful by- 

 products. During 1937, investigations dealing with the preservation 

 of fishery byproducts were carried on in the Seattle technological 

 laboratory under the supervision of Roger W. Harrison, technologist 

 in charge, with the assistance of Andrew W. Anderson, assistant 

 technologist (subsequently transferred to the market news service); 

 Robert E. Silver, junior chemist; and Leslie Lo wen, Neil Nellis, and 

 Robert Rucker, research associates and student assistants; and in 

 our College Park technological laboratory under the supervision of 

 of James M. Lemon, technologist in charge, with the assistance of 

 S. R. Pottinger, junior technologist; M. E. Stansby, junior chemist; 

 Joseph F. Puncochar, junior bacteriologist; and Harold E. Crowther, 

 R. H. Flowers, and C. E. Swift, research associates and student 

 assistants. 



UTILIZATION OF SALMON-CANNERY TRIMMINGS 



In previous reports we have discussed the economic importance of 

 the waste accumulated during the preparation of salmon for canning 

 and the progress being made in the Bureau's studies on methods of 

 utilization. During 1937, we had hoped to extend this work to pilot 

 plant operations but due to unforeseen delays in getting the new 

 technological laboratory building in Seattle, Wash., in readiness such 

 studies were necessarily postponed and the investigation was confined 

 to work permitted by the facilities of the chemical laboratories. 



In view of this, a rather extensive survey was made on the chemical 

 and physical properties of the oil obtainable from the various com- 

 ponents of salmon waste and from the total waste of the five species of 

 salmon from the principal fishing areas of this fish in the United 

 States and Alaska. As indicated in our last report, it is possible to 

 obtain oils having quite widely varying properties. The chemical 

 studies on these samples were continued during the past year for the 



