The Influence of Chronic Fluorine Toxicosis in Laying Hens Upon the Fluorine Content of the Egg and Its Relation to the Lipoid Content of the Egg Yolk

Abstract
The addition of fluorine in the form of rock phosphate to the rations of laying hens results in a distinct and measurable increase in the fluorine content of the eggs. The fluorine accompanies the constituents of the egg yolk. It is completely separated from the non-fat portion of the yolk by extraction of the fatty constitutents with ether or ethyl alcohol. It appears that the fluorine wholly or in large part at least, remains with the acetone-insoluble portion of the fat-like substances of the egg yolk. This suggests that fluorine is deposited in the egg in combination with the complex lipoids of the yolk. It appears that fluorine is present in minute quantities in the normal egg. Increased fluorine ingestion did not reduce the size of the eggs in this series of experiments. The possibility of harmful effects arising from eggs from fluorine fed hens is discussed.