[The effects of cadmium on the levels of insulin in smelters].

OBJECTIVE

To investigate the effects of cadmium on the levels of insulin and blood glucose in exposed workers.

METHODS

Ninety-eight cadmium-exposed workers in a smeltery in the mid-south district of our country were selected as the exposed subjects while the healthy doctors in the workers hospital who were not exposed to the cadmium were treated as the control. The subjects were grouped according to the exposure time, the blood cadmium and the urine cadmium. The variety of the level of serum insulin was investigated for the workers in different groups of the exposure time, the blood cadmium and the urine cadmium. The variety of the levels of the blood zinc and urine zinc were also determined. The relationships among the blood cadmium, the blood zinc and the serum insulin were analyzed.

RESULTS

The level of blood glucose in the group of the exposure time of more than 20 years [(4.9 +/- 0.6) mmol/L] was significantly higher than that in the control group [(4.6 +/- 0.60) mmol/L] with significantly statistical difference (P < 0.01). The level of serum insulin in the group of the exposure time of more than 10 years [(8.58 +/- 4.91) microIU/ml] was significantly lower than that in the control group [(11.57 +/- 5.42) microIU] with the significantly statistical difference (P < 0.05) and the level of serum insulin would be decreased significantly with the increase of the blood cadmium and urinary cadmium. The level of the urine zinc was increased significantly in the workers of the exposure time of more than 20 years. The correlation analysis indicated that the negative correlation was found between the level of serum insulin and the level of blood cadmium, as well as between the level of the serum insulin and the level of the urinary cadmium; the positive correlation was found between the level of blood glucose and the level of insulin, as well as between the level of blood glucose and the level of C peptide in serum.

CONCLUSION

The exposure to cadmium can cause the decrease of serum insulin and may affect the level of blood glucose.