Rabbits were given repeated ear vein injections of saline and aqueous suspensions of exceedingly fine quartz, Rand mine dust, sillimanite, orthoclase, muscovite, rutile, glass and mixtures of mine dust and coal. The total doses varied in animals that did not die prematurely between 60 and 360 mg. of material. The period of observation was likewise variable but for each dust some animals survived well over a year.
The authors note the occurrence of silica shock incident to injecting fine quartz and attribute it to change in the normal hydrogen concentration of the blood serum.
They note the development of typical silicotic lesions in the spleen, liver, lymph nodes and bone marrow on injecting quartz and mine dust and the inert type of reaction caused by the other pure minerals, thus confirming observations made in the Saranac Laboratory, where this method originated. They discovered lesions in the kidneys, pancreas and adrenal