Mutagenicity and cytotoxicity of coal fly ash from fluidized-bed and conventional combustion.

In summary, fly-ash samples from a pressurized fluidized-bed combustion miniplant were found to consist of submicron, irregular particles that were cytotoxic and contained bioavailable mutagens. The fly-ash emission sample from a conventional coal-fired power plant was found to consist of spherical particles that were also cytotoxic but less mutagenic. The FBC fly ash investigated here was collected from an experimental miniplant and should not be considered representative of fly ash that may be obtained in the future from larger commercial-scale FBC plants. Further health and environmental assessment studies of coal fly-ash samples collected at multiple sites, including commercial-scale fluidized-bed and other conventional combustors, are needed to evaluate the potential health effects of coal fly ash from both types of combustion technology.