Red oak condensate: its apparent lack of cytotoxic and genotoxic effects as compared with three other wood-drying condensates.

A major activity of the lumber industry is the kiln-drying of wood. In order to ascertain whether wood-drying condensates pose a possible environmental hazard, the cytotoxicity and genotoxicity of these condensates in vitro, were tested using an assay validated using Chinese hamster ovary (CHO) cells and a known genotoxicant, mitomycin C. Subsequently, the assay was developed for the human peripheral blood lymphocyte (HPBL) system, as it was felt that results derived from human cells would reflect the situation more closely in vivo. Condensates from Southern yellow pine, Eastern white pine and Douglas fir trees were tested in CHO and HPBL systems and have demonstrated cytotoxic and genotoxic effects in vitro, as reported elsewhere. Red oak condensate has also been tested using the HPBL system. Thus far, results are consistent with the hypothesis that there is no difference between the cytotoxic and genotoxic effects of treated cells versus controls. This finding indicates either that the condensate of red oak poses no appreciable genetic hazard as measured by cytotoxicity and genotoxicity assays, or that the condensate has lost its potency with time and storage; both of these possibilities have important environmental implications.