Further studies of blood levels of some tumor markers in the area polluted by polychlorinated biphenyls and control population.

摘要

The levels of beta2-microglobulin (beta2-m), alpha-fetoprotein (AFP) and thyroglobulin (TG) were measured in the serum of 245 employees of chemical factory formerly producing polychlorinated biphenyls (PCB) consisting of 54 males (age range 24-65 years, median 45) and 191 females (age range 20-69 years, median 45). The control population consisted of 636 adults from control areas of northwest and east Slovakia. The frequency of beta2-microglobulin levels lower than 1.6 microg/ml in 242 employees of chemical factory was 76.8% (186/242) which was three times higher (P<0.001) than 24.4% (155/635) in 636 controls. Still more remarkable difference was obtained when using the cut/off level of 1.2 microg/ml, the frequency of such values in the employees being 45.4% (110/242) vs. 4.4% (28/635) in the controls. In contrast, no difference in alpha-fetoprotein levels was observed between the employees and the controls, the respective frequency of these < 5.0 ng/ml being 87.6% (212/242) vs. 86.2% (389/451) and these < 10.0 ng/ml being 100.0% (242/242) vs. 97.8% (441/451). Similarly, the frequency of normal thyroglobulin levels < 50.0 ng/ml) did not differ, being 95.6% (174/182) in the employees and 87.9% (87/99) in the controls. Most of a total of 20 cases with thyroglobulin level > 50.0 ng/ml showed sonographicaly enlarged and multinodular thyroid with focal or diffuse hypoechogenicity, three of them showed solitary nodule with a diameter > 10 mm. Although the decreased levels of beta2-microglobulin might be somehow related to the modulation of immune system, more plausible explanation appears to be the possible impairment of renal tubules by PCB similar to that caused by heavy metals resulting in increased urinary excretion of beta2-microglobulin and decrease of its blood level.