Rw. West et al., NEOPLASTIC TRANSFORMATION OF NEONATAL HUMAN FIBROBLASTS EXPOSED IN-VITRO TO RADIATION FROM A QUARTZ-HALOGEN LAMP, Photodermatology, photoimmunology & photomedicine, 11(3), 1995, pp. 119-123
The use of unfiltered quartz-halogen lamps exposes human skin to radia
tion that spans much of the ultraviolet (UV) spectrum. Reports indicat
e that exposure to quartz-halogen lamps is erythemogenic, mutagenic, a
nd carcinogenic. To compare the carcinogenic potential of quartz-halog
en lamps with that of other UV sources, we determined the dose depende
nce for cytotoxicity and neoplastic transformation in neonatal human f
ibroblasts exposed in vitro to: a 15 W germicidal lamp (primarily 254
MI radiation), a 15 W Cool White fluorescent lamp, and an unfiltered 2
0 W quartz-halogen lamp. Fluence-survival relationships were multiphas
ic with linear dose response below about 40% survival, and all three s
ources produced fluence-dependent transformation as indicated by induc
tion of anchorage-independent growth. Maximum transformation frequenci
es were observed at fluences of 5-8 J/m(2) for the germicidal lamp, 6.
3 kJ/m(2) for the fluorescent lamp, and 300 J/m(2) for the quartz-halo
gen lamp. These data confirm the carcinogenic potential of the quartz-
halogen lamp.