Douglas-fir: a third wood-drying condensate found to exhibit in vitro cytotoxicity and genotoxicity

The present study applies the approach described in Mark et al. for the testing of toxic chemicals produced during the drying of Douglas-fir. The genotoxic potential of Douglas-fir condensate has been previously unexplored and is thus an area of appropriate concern to the forest products industry, regulatory, agencies, and the general public. Previous research conducted in this laboratory has identified two wood-drying condensates that yield positive cytotoxic and genotoxic effects. The results of testing Southern yellow pine and Eastern white pine condensates have been reported elsewhere. Douglas-fir condensate, a third wood-drying condensate, was added in vitro in concentrations ranging from 0.1 to 100 microliters/ml to cultures of Chinese Hamster Ovary (CHO-WBL) cells. A dose response curve was observed with this condensate for both cytotoxicity and genotoxicity. The number of viable cells as well as the mitotic index (MI) and proliferative rate index (PRI) varied inversely with dosage. The result of chromosome aberration (Abs) analysis and sister chromatid exchange (SCE) analysis, both cytogenetic measures of genotoxicity, also gave statistically significant results.