THE INHIBITING EFFECT OF PABA ON PHOTOCARCINOGENESIS

The efficacy of a 5% solution of para-aminobenzoic acid (PABA) to protect against photocarcinogenesis was tested in 6 groups, each of which contained 30 light pigmented hairless mice. The light source was a Phillips TL 40 W/12, which mainly emits UVB. PABA significantly retarded the tumor induction time (p<0.05) and reduced both tumor yield and carcinoma yield (p<0.05). The dorsal skin of the mice was removed and weighed. The mean weight of UVR-exposed mice skin protected with PABA did not differ from that of the controls, but in the non-protected UVR-exposed mice the skin samples were significantly heavier (p<0.05). © 1990 Springer-Verlag.