The story of indium as a nutritional sensation originated in early seventies with
the research conducted by Dr. Henry Alfred Schroeder from the Darthmouth School
Below we include a brief report on that research as described in two papers published
in the Journal of Medicine. However, we expect our critically thinking readers
to check us on everything we report and we gladly give tips and help on how to do it.
There is a vast database of scientific papers related to medicine, maintained
by the government, and available to the general public on the internet. It is called
Once you locate a paper of interest in the database you have to go to the public library
to find and read the content. Sometimes, but not always, the abstract is published online.
To locate the papers of Dr. Schroeder related to indium studies type "Schroeder AND indium" in the query window.
If you narrow your search by adding the "mouse" keyword you will find the two papers
Scandium, chromium(VI), gallium, yttrium, rhodium, palladium, indium in mice: effects on growth and life span. J Nutr. 1971 Oct;101(10):1431-7. No abstract available. PMID: 5098882 [PubMed - indexed for MEDLINE]
If you follow the links you will be able to read the abstract of the first paper.
No abstract of the second paper is available in PubMed. For your convenience we include
the missing abstract here.
Scandium, Chromium(VI), Gallium, Yttrium, Rhodium, Paladium, Indium in Mice:
Effects on Growth and Life Span
HENRY A. SCHROEDER and MARIAN MITCHENER Department of Physiology, Dartmouth Medical School, Hanover,
New Hampshire 03755 and Brattleboro Memorial Hospital,
Brattleboro, Vermont 05301
ABSTRACT In order to evaluate possible innate toxic effects of small doses
of scandium, hexavalent chromium, gallium, yttrium, indium, rhodium and
palladium in terms of growth and survival, 958 mice divided as to sex were raised
in an environment limited in metallic contamination and given 5 ppm metal in drinking
water from weaning until natural death. Body weight was measured at monthly
intervals up to 6 months, at 1 year and at 18 months of age. The feeding of gallium
was accompanied by significant but not marked suppression of weight at 14 of 16
intervals in both sexes; the feeding of scandium was associated with growth suppression
at 10, of indium at 8, of palladium at 7 and of rhodium at 6 of 16 intervals compared
to mean weights of controls. The feeding of yttrium and hexavalent chromium were associated
with significant lessening of growth at 12 and 8 of 16 intervals, respectively. Survival
of gallium-fed females at older ages was less than that of controls, whereas survival
of palladium-fed males and yttrium-fed mice of both sexes were greater. Tumors were found
at necropsy in 16.3% of one group of controls, 27.4% of the scandium, 26.0% of the gallium,
13.0% of the indium, 28.8% of of the rhodium and 29.2% of the palladium groups. Malignant
tumors were increased in rhodium and palladium groups, at a minimally significant level
of confidence (P < 0.05), all but one tumor being malignant. In a second series, tumors were
present in 26.8% of controls, 27.6% of the mice fed chromium(VI) and 33% of the mice
fed yttrium appear to exhibit slight carcinogenic activity in mice.
J. Nutr. 101:1431-1438, 1971
In these experiments mice devided into 7 test groups (scandium, chromium, gallium,
yttrium, palladium, and indium group) plus the control group were kept for life
in the same conditions. Each group was fed the same diet consisting of rye flour,
powdered milk, and vegetable oil enriched with vitamins and few essential minerals.
They were all given spring water cleared from metallic contaminants by deionizing process.
The difference was that each group, except for the control, had one specific trace element
added to their drinking water. When they died they were dissected
and different measures were taken.
The indium group were given indium in the form of indium chloride (InCl3) with water
containing 5 ppm of the mineral. The table below demonstrates how non-essential element indium
raised the uptake of several essential minerals in different organs in mice. The table is
somewhat simplified showing only the average amount of metal in an organ. Those who want
to evaluate the statistical significance of the numbers shown should read the original
paper and examine standard deviations.
Essential trace metals in tissues of both sexes of mice