The influence of lead on the biomechanical properties of bone tissue in rats

Environmental lead (Pb) is a serious public health problem. At high levels, Pb is devastating to almost all organs. On the other hand, it is difficult to determine a safe level of exposure to Pb. More than 90% of the Pb in the adult human body and 70% in a child's body is stored in the bones. In the presented study, the effects of lead exposure on bones were studied for rats treated orally with Pb acetate in drinking water for 14 days. The hypothesis was tested that lead exposure negatively affects bone structure. Femur strength was measured in a three-point bending test, whereas infrared spectroscopy (FTIR) was used to measure molecular structural changes. Lead significantly decreased the ratio of area of two types of vibrational transitions, which are highly specific to mineral to matrix ratio. The results of the biomechanical study show that femurs of rats treated by Pb-acetate appeared to be weaker than bones of the control group, and may produce a condition for the development of higher risk of fractures. Additionally, a great difference in body mass was observed between control and the Pb acetate-treated groups. The lower bone mineral content and the weaker mechanical properties of bones from Pb-treated rats are associated with the pathologic state dependent of the exposure of lead.