BUREAU. OF CHEMISTRY. 



427 



Food and drug samples examined in the various branch laboratories during the fiscal year 



ended June 30, 1911. 



BOSTON LABORATORY. 



The work at the Boston laboratory was, as usual, about equally- 

 divided between import and interstate samples. The following 

 special investigations have been continued or undertaken during the 

 year: 



Fish. — Work to detect, chemically, slight decomposition taking 

 place in fish was continued from last year. This has been confined 

 primarily to the sardines of the Maine coast, which, when caught 

 rilled with "red feed," a small crustacean, decompose very rapidly, 

 and in a few hours, under usual conditions, are unfit for packing. 

 The corrosion of unprotected tin containers by sardines in mustard 

 sauce, as shown by periodical examinations of a lot packed under the 

 supervision of the laboratory, showed that after processing the con- 

 tents of the cans of the size known as eighths, contained about 200 mg 

 of tin per. kilo, which amount rapidly increased during four months' 

 storage, at the end of which time about 800 mg per kilo were present. 

 The packers have now generally adopted lacquered tins for these goods. 



Arsenic in shellac used in connection with food. — An in- 

 vestigation was made of the content of arsenic in shellac of all kinds, 

 but particularly in such brands as are used bj^ confectioners for coat- 

 ing candy and by brewers as a varnish for their vats and other recep- 

 tacles. Early in the year a confectioner's shellac was examined 

 which contained 0.2 per cent of arsenic. This led to a stiulj of such 

 shellacs, and all examined were found to contain more or less arsenic, 

 which is added in India in the form of the yellow sulphid to improve 

 the color of the product, enabling an inferior product to be sold as a 



