206 U. S. BUREAU OF FISHERIES 
STUDIES OF METHODS OF PREPARING CRAB MEAT 
At the request of a group of crab-meat packers, funds were provided 
to this Bureau by Congress, effective July 1, 1938, for the purpose of 
making a chemical and bacteriological investigation of existing methods 
of preparing crab meat, in the hope that improvements in such 
methods could be recommended to the industry. The 6 months 
which have been devoted to this survey have been concerned largely 
with the bacteriological phases of the problem. Following a survey 
of equipment and methods used by the packers of crab meat in the 
Chesapeake Bay area, a temporary field laboratory was established 
at Crisfield, Md., in which bacteriological and chemical examinations 
of commercial samples of prepared crab meat were made for the 
purpose of making definite recommendations designed to improve 
handling practices. 
As a result of a thorough study of the methods employed by the 
various crab-packing plants, several recommendations were made 
to the packers which should result in definite improvement of the 
product. A detailed report on the results obtained thus far in this 
investigation has been prepared and will be published in the near 
future. 
PHARMACOLOGICAL STUDIES 
As more has become known in recent years’ concerning the impor- 
tance and significance of fishery products in the diet of man and his 
domestic animals, there has been an increasing demand for knowledge 
concerning the physiological effects of the different constituents of 
fishery products under the varying conditions under which they are 
manufactured and included in man’s diet or in the rations of live- 
stock. This particularly involves the metabolism of mineral constitu- 
ents such as copper, arsenic, and fluorine. It also concerns studies 
of possible toxicity of products such as fish meal when improperly 
manufactured, or when decomposed due to careless conditions of 
handling after manufacture and before reaching the feed manufac- 
turer or ultimate consumer. 
CHEMICAL AND PHARMACOLOGICAL STUDIES OF THE FLUORINE IN 
FISHERY PRODUCTS 
As stated in the 1937 report of this Division, a high content of 
fluorine in the diet has been responsible for mottled enamel of teeth 
in both man and domestic animals. In cases where this difficulty has 
been particularly noticeable, the fluorine has been traced to mineral 
mixtures of inorganic origin incorporated in the diet. However, as 
a result of this difficulty, there has been a demand for more knowl- 
edge concerning the fluorine content of such food products as meat 
and fish and the physiological effect of fluorine from a natural food 
source as compared with fluorine of inorganic origin. Because of 
this situation, our technologists, in 1937, began chemical and phar- 
macological studies of fluorine in fishery products. Our work thus 
far has been confined to canned salmon and canned mackerel. Chem- 
ical analyses of the samples used in the tests showed a content of 5.8 
parts per million of fluorine in the salmon on a fresh basis and 27 
Pa 
