Crude coal tar (CCT) contains polycyclic aromatic hydrocarbons (PAHs). Benzo[a]pyrene (BaP) is metabolized into a highly reactive metabolite benzo[a]pyrene-7,8-diol-9,10-epoxide (BPDE) that is able to bind to DNA and creates BPDE-DNA adducts.
Adducted DNA becomes immunogenic and induces immune response by production of antibodies against BPDE-DNA adducts (Ab-BPDE-DNA). Circulating Ab-BPDE-DNA was proposed as potential biomarker of genotoxic exposure to BaP (PAHs).
Goeckerman therapy (GT) of psoriasis uses dermal application of CCT ointment (PAHs). In presented study (children with psoriasis treated by GT; n = 19) the therapy significantly increased the level of Ab-BPDE-DNA (EI = 0.29/0.19-0.34 vs. 0.31/0.25-0.40; median/lower-upper quartile; p < 0.01).
The results support the idea of Ab-BPDE-DNA level as a possible tentative indicator of exposure, effects and susceptibility of the organism to the exposure of BaP (PAHs).