The following investigation of the condition of foods packed in tin cans was prompted by an alleged case of poisoning, which occurred at Mansfield, Ohio, in April, 1890.  A man and woman were reported to the writer as having been made sick by eating pumpkin pie made from canned pumpkin.  The attending physician pronounced the case one of lead poisoning.  The wholesale dealer from whose stock the canned pumpkin originally came, procured a portion of the same at the house where the poisoning occurred, and sent it to the writer for examination.

The results of the examination as reported in Serial No. 552, below, showed that the canned pumpkin contained an amount of stannous salts equivalent to 6.4 maximum doses and 51.4 minimum doses of stannous chloride per pound.  On being notified of this fact, the dealer sent a can of the same brand of pumpkin from his stock.  The inner coating of the can was found to be badly eroded, and upon examination, as reported in Serial No. 563, below, one pound of the pumpkin contained tin salts equivalent to 7 maximum and 56 minimum doses of stannous chloride.

The unexpected large amount of tin salts in such an insipid article as canned pumpkin, and the claimed ill effects of the consumption of the same, suggested the advisability of extending the investigation to other canned goods in common use.  Accordingly a line of articles was purchased in open market as sold to consumers, no pains being taken to procure old samples.  The collection embraced fruits, vegetables, fish and condensed milk.  With the exception of the condensed milk, every article examined was contaminated with salts of tin.  In most cases the amount of tin salts present was so large that there can be no doubt of danger to health from the consumption of the food, especially if several kinds are consumed at the same meal.

METHOD.

The method employed in the determination of the tin was simply as follows: 

The contents of each can were emptied into a large porcelain dish, and the condition of the inner coating of the can noted.  After thoroughly mixing the contents, fifty grammes were weighed off and incinerated in a porcelain dish of suitable size.  The residue was treated with a large excess of concentrated hydrochloric acid, evaporated to dryness, moistened with hydrochloric acid, water was added, and the mass was filtered and washed, the insoluble matter being all washed upon the filter.  After drying the filter with its contents, the whole was again incinerated in a porcelain dish and the residue treated as before.  The solution thus obtained was properly diluted and saturated with hydrogen sulphide.  After standing about twelve hours in a covered beaker the precipitate was filtered off and the tin weighed as stannic oxide.

RESULTS OF EXAMINATION.

Serial No. 552.—­Sample of canned pumpkin, received of F.A.  Derthick, April 22, 1890, sent by Albert F. Remy & Co., Mansfield, Ohio.  Pie made from it supposed to have made a man and woman sick.  The attending physician pronounced the case one of lead poisoning.