In the previous article1we described in detail a method of determining quantitatively minute amounts of arsenic in biologic material. In order that a conclusion not influenced by a normal variation can be obtained from this series of analyses, it has been necessary to make a study of the possible arsenic content both in patients who are receiving and in those who have never had any treatment whatever in which arsenic is used as a remedial agent. The ingestion of foods prepared by artificial processes, fruits which may have been sprayed with arsenical solutions, sea food which in some localities is contaminated to a large degree with arsenic, copper, etc., candy made from glucose, together with a large variety of other possibilities of arsenic ingestion, makes it necessary to gain some idea as to the "normal" arsenic content among our patients. Gautier and Clausmann2analyzed a variety of food articles,