More than 500 whole blood samples of normal subjects from Germany collected
in 1991-1996 have been analyzed for polychlorinated dibenzo-p-dioxins (PCD
D) and dibenzofurans (PCDF) by capillary gas chromatography/high-resolution
mass spectrometry. Over the examined time period a continuous decrease of
the PCDD/F concentrations in human blood was observed. The mean levels foun
d were about 42.7 pg I-TEq/g (lipid basis) in 1991 and 20.7 pg I-TEq/g (liq
uid basis) in 1996 {median: 40.8 and 19.2}. A reduction to about half was f
ound for most congeners. Each 1-year subset of the, entire collective shows
a positive correlation of the PCDD/F blood levels with age for most of the
congeners, the sum values, and the calculated toxicity equivalents. For st
atistical evaluation a multiplicative model was used: Concentration in bloo
d=A.age(B). The correlation is mostly pronounced for lower chlorinated PCDD
and for 2,3,4,7,8-PentaCDF. (C) 2000 Academic Press.