A hundred and twenty 21 day-old Wistar male rats were divided into four groups: each group was given drinking water containing 0 (control), 1, 5 and 10ppm of cadmium daily. After four weeks, a hematological test, bending and compressive strength tests of the long bones and a cadmium determination of bone were carried out. The right femur and humerus were used for the bending test, and the left ones for the compressive test. The compressive strength of the diaphysis and the metaphysis were measured respectively by using the crosscut portions of bone.
The bending strength, elasticity and deflection were statistically insignificant between the control and the cadmium groups. The strength to resist the compressive stress, which is a component of the bending stress, reduced in the diaphysis of the 5 and 10ppm groups and in the metaphysis of the 10ppm group. Dose related changes in the elasticity and deformation in compression tests were not observed.
The hematological results of the 1ppm group were not different from those of the control group. In the 5 and 10ppm groups, anemia, decrease in serum iron and BUN and increase in serum phosphorus were observed, and the differences between the control and the 10ppm groups were larger than those between the control and the 5ppm groups. In the 10ppm group, the serum Alp activity also decreased.
The cadmium concentrations were 12.7±8.4, 20.6±8.4, 74.3±18.7 and 127.3±23.2ng/g dry weight of the femur and 10.1±2.8, 17.0±4.3, 101.0±22.5 and 134.5±35.4ng/g dry weight of the humerus in the control, 1, 5 and 10ppm groups respectively.
