1 (BtQ) 2 (BhQ) nants that have been detected in automobile exhaust, urban air particulates, and cigarette~ moke.~-~ BfQ and BhQ have been shown to be metabolically activated to products mutagenic to Salmonella typhimurium. 5-8 In contrast to BfQ and BhQ, their carbon analogue phenanthrene is nonm~ tagenic.~ In a previous paper, 1 we have described the synthesis of dihydrodiol and diol epoxide derivatives of benzo [flquinoline. Since we are ...