Exposure and risk assessment of the Czech population to chlorinated pesticides and polychlorinated biphenyls using archived serum samples from the period 1970 to 1990
Abstract
The serum samples from the years 1970-1990 archived at the temperature of -20oC in the biobank primarily intended for serological survey performed in the CR since 1960 were pooled and analyzed for DDT, its metabolites, HCB, HCHs, and indicator PCB congeners using up-to-date GC/MS/MS methods to retrospectively assess health risks according to current health guidelines. Samples were pooled based on the decade of sampling, age, gender, and three geographical areas; in adults, one pooled samples consisted of ten and in children of twenty individual samples.
Altogether 233 pooled samples were analyzed. For all organochlorine pesticides (OCPs), significant downward trends were observed in the period 1970-1990 (p<0.001).
The levels of HCB exceeded the Biomonitoring Equivalent (BE) value. The hazard quotient (HQ) in Prague and Ostrava during the 1970s and 1980s was about 40 and in the 1990s it had dropped to about five.
In Uherské Hradiště, the HQ in 1975 was one order of magnitude higher (about 170), and had decreased to approximately 12 by 1987. For both HCB and the DDT sum, the BE-related carcinogenic risk of actual concentrations in the past exceeded significantly the individually accepted cancer risk level of 10(-4).
The levels of the main PCB congeners in the 1970s through 1990s revealed an upward time trend in all analyzed strata. The highest concentrations were found in the serum of residents from the hot-spot area Uherské Hradiště.
Critical PCB sum concentration levels (700ng/g lipid for vulnerable population groups and 1800ng/g lipid for other population groups) were substantially exceeded with an increasing time trend. PCB sum had exceeded HBM II values of 7μg/L of serum since 1980 in all age strata.
In conclusion, the body burden of the Czech general population relative to persistent organic pollutants (POPs) in the period 1970 through 1990 significantly exceeded currently existing health based limit values.