From time to time, during the past twelve years, paragraphs have
appeared in newspapers and other periodicals tending in effect to warn
the public at least against the indiscriminate use of canned foods. And
whenever there has been any foundation in fact for such cautions, it has
commonly rested on the alleged presence and harmfulness of tin in the
food. At the worst, the amount of tin present has been absurdly small,
affording an opportunity for one literary representative of medicine to
state that before a man could be seriously affected by the tin, even if
it occurred in the form of a compound of the metal, he would have to
consume at a meal ten pounds of the food containing the largest amount
of tin ever detected.

But the greatest proportions of tin thus referred to are, according to
my experiments, far beyond those ever likely to be actually present in
the food itself in the form of a compound of tin; present, that is to
say, on account of the action of the fluids or juices of the food on the
tin of the can. Such action and such consequent solution of the tin, and
consequent admixture of a possibly assimilable compound of tin with the
food, in my opinion never occurs to an extent which in relation to
health has any significance whatever. The occurrence of tin, not as a
compound, but as the metal itself, is, if possible, still less
important.

During the last fifteen years I have frequently examined canned foods,
not only with respect to the food itself as food, and to the process of
canning, but with regard to the relation of the food to, or the
influence if any of the metal of, the can itself. So lately as within
the past two or three months I have examined sixteen varieties of canned
food for metals, with the following results:

Decimal parts of
a grain of tin
(or other foreign
metal) present in
Name of article a quarter of a lb.
examined.

Salmon none.
Lobsters none.
Oysters 0.004
Sardines none.
Lobster paste none.
Salmon paste none.
Bloater paste 0.002
Potted beef none.
Potted tongue none.
Potted "Str