Potential for genetic damage from multivitamin solutions exposed to phototherapy illumination.

The ability of standard phototherapy illumination to produce damage in intracellular DNA is well established. In this study, the addition of a dilute solution (1:6400) of a clinically-used multivitamin concentrate to human KB cells was found to enhance the generation of single-strand DNA breaks produced by broad-spectrum fluorescent light. The effect of the exogenous photosensitizing agent (multivitamins) was blocked by the enzyme catalase; thus, the photoproduct responsible for the DNA modification was hydrogen peroxide, an extremely reactive molecule capable of damaging a variety of biologic macromolecules.