“…Such concerns seem justified in view of DNA modifying activity of phototherapy (9), a property shared with many chemical carcinogens and teratogens (1). The photodynamic damage of intracellular DNA has been well characterized and is enhanced by, but not dependent upon, the presence of exogenous photosensitizing agents (3,7,10,11). Such enhancement takes on clinical significance when it is realized that many low birth-weight infants receiving phototherapy are simultaneously administered parenteral hyperalimentation solutions containing photosensitizers, i.e., multivitamins, amino acids, etc.…”