The filamentous fungus Cunninghamella elegans IM 1785/21Gp has an ability to remove phenanthrene to hydroxylated products with high efficiency. The sensitivity of C. elegans spores to phenanthrene derived metabolic products, 9-phenanthrols, as a model example of hydroxyderivatives produced by this fungus, was determined in this work. Calorimetric measurements showed that 9-phenanthrol disturbed the metabolic activity and spore germination of C. elegans less than phenanthrene did. However, at concentrations exceeding 60-70 mg L-1, phenanthrol strongly affected the intracellular processes of this fungus. (c) 2004 Elsevier B.V. All rights reserved.