The Goeckerman regimen (GR) for the treatment of
psoriasis comprises dermal application of crude
coal tar (
polycyclic aromatic hydrocarbons, PAHs) and exposure to ultraviolet radiation (UVR). PAHs and UVR are mutagenic and carcinogenic agents. We evaluated dermal absorption of PAHs as well as the mutagenic and genotoxic effects of GR in 16 children with
psoriasis, by determining levels of
1-hydroxypyrene (1-OHP), 1-,2-,3-,4-hydroxyphenanthrene, (1-OHPhe, 2-OHPhe, 3-OHPhe, and 4-OHPhe), urinary mutagenicity (Salmonella mutagenicity assay, Ames test) and numbers of
chromosomal aberrations in peripheral lymphocytes (CA), in urine and/or blood, before and after GR. The
Psoriasis Area and Severity Index (PASI) score was used to evaluate clinical efficacy of GR. Compared with pre-treatment levels, there were significant increases in urinary concentrations of 1-OHP (p<0.001), 1-OHPhe (p<0.001), 2-OHPhe (p<0.001), 3-OHPhe (p<0.001), and 4-OHPhe (p<0.01), indicating a high degree of dermal absorption of PAHs. There were also significantly increased numbers of revertants in the Ames test in two different strains (YG1041-S9, p<0.01; YG1041+S9, p<0.001; TA98+S9, p<0.01), which demonstrates urinary mutagenicity. We also found a significant increase in the number of CA (p<0.001) and significantly decreased number of CA (p<0.01) at 81 days post-treatment, suggesting that GR has a temporary genotoxic effect. The PASI scores were significantly decreased after
GR (p<0.001), confirming the clinical benefit of GR. In conclusion, our results demonstrate mutagenic and temporary genotoxic effects of GR in the group of 16 treated child patients.