The concentration of selected cancer markers (TPA, TPS, CYFRA 21-1, CEA) in workers occupationally exposed to arsenic (As) and some heavy metals (Pb, Cd) during a two-year observation study.

OBJECTIVE

Molecular epidemiology studies have lately been focused on occupational cancer associated with exposure to chemical carcinogens in work environment. Measuring serum levels of tumour markers ie. the substances produced in transformed cells, is a modern method used in the prevention or early detection of cancer. A two-year observation study was constructed to investigate the relationship between arsenic, lead, and cadmium concentrations and the levels of cancer markers: TPA (tissue polipeptide antigen), TPS (tissue polipeptide specific antigen), and CYFRA 21-1 in 69 male workers occupationally exposed to As and Pb, and environmentally exposed to Cd via tobacco smoking.

RESULTS

Significant correlations were found between CEA and blood Cd concentrations or between CEA and period of work under exposure. Multiple regression tests revealed also relationships between some cancer markers and the work period, and thereby the lifetime exposure to heavy metals. Duration of work under exposure significantly influenced TPA and TPS concentrations in these models. All the metals examined were found to have influence on the concentration of cancer markers, except for CYFRA 21-1, but the direction of this influence varied. Lead (especially FEP level) and cadmium were also among the metals affecting TPA concentration profile, although the multiple regression ratio for Cd-TPA correlation was negative.

CONCLUSIONS

The strong positive correlation between blood concentrations of Cd and CEA, the marker of abnormal cellular differentiation, may reflect neoplastic transformation of normal cells stimulated by some carcinogens (e.g. cadmium). All the examined carcinogenic, or potentially carcinogenic metals (As, Cd, Pb) belong to the group of factors having impact on serum TPS and/or TPA concentrations in exposed workers. No correlation was found between CYFRA 21-1 and any metal studied but it is plausible that changes in the concentration level of this marker might be revealed after a longer observation period.