PW08 Aquatic Ecotoxicology II
Exhibit Hall
8:00 AM - Wednesday
(PW139) Toxicity and EROD-inducing potency of alkylated polycyclic aromatic hydrocarbons (PAHs) in fish.
Turcotte, D1, Hodson, P1, Brown, R1, 1 Queen's University, Kingston, Ontario, Canada
ABSTRACT- Previous embryo toxicity tests with Japanese medaka (Oryzias latipes) have indicated higher toxicity of C1-C4 alkyl-phenanthrenes (alkyl-PHE) and alkyl-anthracenes (alkyl-ANT) than the non-alkylated PHE and ANT compounds. The general toxicity of PHE and ANT is known to be enhanced by activation processes, including activation by cytochrome oxidases (CYP) from postmitochondrial supernatant fraction (S9 fraction) and photoactivation by light. Initial experiments in our group have suggested a link between intrinsic activation of C1-C4-PHE by Cytochrome oxidases and the enhanced toxicity of the alkylated compounds. In this work, we are investigating the S9 and photoactivation of alkyl-PHE and alkyl-ANT to compare the effects on toxicity with activation of PHE and ANT. Toxicity will be indicated by embryo toxicity of the medaka and by EROD induction in juvenile trout (Oncorhynchus mykiss). Current experiments show that S9 activation of alkyl-anthracenes produces different derivatives than photoactivation. The photo-activated and non activated compounds do not show the same level of toxicity in medaka. A comparison of EROD activity for the alkyl-ANT and their photoactivated derivatives has been done with juvenile rainbow trout. These results show that photoactivation of certain non-inducing PAHs (like anthracene) can yield derivatives that induce EROD activity in fish. Future work will include an investigation of the ability of activated alkyl-ANT to induce EROD activity in rainbow trout, including quantitation at the protein level with immunoblotting of the induced CYP.
Key words: EROD, PAHs, Fish, toxicity