Retrospective study of concentration levels of Pb, Cd, Cu and Se in serum of the Czech population in time period 1970-1999.

The retrospective study evolution of trends in concentrations of Cd, Pb, Cu and Se in the population of the Czech Republic over 30 years period could be useful in design of regulations concerning health protection, prevention of diseases caused by deficiency of trace elements and have considerable economic importance. Concentrations of the named elements in the serum were determined by means of atomic absorption spectrometry (AAS) after mineralisation in a microwave digestion system. The 1433 samples of serum (730 males and 703 females, average age 48.7 and 49.1 years respectively) from a time period 1970-1995 were obtained from the Serum bank of National Institute of Public Health and volunteers (1999). Serum samples from the years 1970, 1975, 1980, 1985, 1990, 1995 and 1999 were examined. The accuracy of the results was checked by means of the Control material Seronorm Whole Blood 404,107 and Seronorm Serum 704,121, Nycomed. The concentration of Cd had a decreasing trend for the years 1975-1999 (0.82 microgram Cd.l-1 vs 0.47 microgram Cd.l-1). The levels of Pb are falling in the interval 1970-1980 (15.6 micrograms Pb.l-1 vs. 6.6 micrograms Pb.l-1). In year 1985 concentration of Pb increased (10.7 micrograms Pb.l-1) but subsequently decreased again (1995--6.4 micrograms Pb.l-1). In year 1999, it was 8.9 micrograms.l-1. The concentration of Cu decreased in period 1970-1990 (1525 micrograms Cu.l-1 vs. 990 micrograms Cu.l-1). From 1990 to 1999 the levels of Cu had an increasing tendency (1999--1060 micrograms Cu.l-1). Levels of Se in the interval 1970-1985 were surprisingly equal (58.1 micrograms Se.l(-1)-54.4 micrograms Se.l-1). However in the interval 1986-1990 the level of Se sharp declined (38.3 micrograms Se.l-1). Since 1990 levels of Se in serum increased again, up to 67.1 micrograms Se.l-1 in 1999. Statistically significant differences between men and women were found only in Cu and Pb concentrations. Concentrations of under study elements corresponded to the published values concerning unexposed population.