Human Bones Solubility in Seawater

Abstract

Introduction: In January 1968, an Israeli submarine "Dakar" sank in the Mediterranean Sea. The Dakar’s wreckage was not found until May 1999, when it was located between the islands of Cyprus and Crete at depth more than 3,000 m by the Nauticos Corporation, the same company which found a British passenger liner "Titanic" that sank in the North Atlantic Ocean after it collided with an iceberg. The possibility to recover any existing remains of the crew members in the sunken submarine “Dakar” and to give them Jewish burial had been widely discussed in Israel. Background: The human bones consist of mineral and organic matrixes. Therefore, the solubility of the bones in seawater will depend on the behavior of these two matrixes. The main mineral component of human bones is a calcium phosphate mineral which is similar in composition and structure to minerals within the apatite group. Thus, the human bones are rigid body tissue consisting of biological cells embedded in an abundant, hard intercellular material. Objective: The main objective is to study the possibility of solubility of human bones after prolonged time in deep waters. Methods: The solubility of minerals in natural waters can be calculated from thermodynamic considerations provided that the equilibrium constants are known, and ionic activity coefficients can be obtained. Using the approaches developed by Pitzer's scientific school for ionic activity coefficients calculations it was demonstrated in this article that neither hydroxyapatite nor fluorapatite can be dissolved in seawater. Results: It is well known, according to various publications, that no skeleton remains were found in most cases of sunken ships wreckage in deep seawaters. The question is how this contradiction can be explained if mineral constituents of human bones could not be dissolved in seawater, but no skeletons have been found in sunken ships being prolonged time in deep depths. We assume that the reason for this phenomenon is that skeleton bones in addition to mineral matrix contain organic constituents which can be dissolved in seawater due to various natural biological and chemical processes. After the dissolution of the organic constitutes of the bones, the bones remains could not be preserved as a whole in sunk ships. Conclusion: It can be assumed that due to the dissolution of human bones' organic contents in seawater, human bodies’ remains cannot be found in most cases in sunken ships after a prolonged time in deep waters.