Enhanced near-ultraviolet light sensitivity induced by coal combustor effluents in cultured mammalian cells

The cytotoxicity of radiation from Westinghouse sun lamps (principal emission 290-340 nm) was enhanced by treatment of cells with nontoxic concentrations of condensate from the gaseous effluent from a pressurized, fluidized-bed coal combustor. The effect was similar to the photoenhanced cell killing induced by nontoxic concentrations of 7,12-dimethylbenz[a]anthracene, a carcinogenic derivative of substances produced by incomplete combusion of fossil fuels. Furthermore, light-dependent cell killing requiring the presence of the condensate was observed even when the sun lamp emission was filtered (principal emission 300-340 nm) to eliminate cell killing due to near-ultraviolet light alone, or when a black light near ultraviolet source (emission maximum, 365 nm) was used. It is suggested that coal combustor effluents may act synergistically with the short-wavelength component of sunlight.