“…Indeed, adverse health effects have been observed in juvenile salmon from the Duwamish Estuary, which is contaminated with PAHs and PCBs. Fish from this area showed immunosuppression, reduced disease resistance and decreased growth rates (Arkoosh et al, 1991(Arkoosh et al, , 1994(Arkoosh et al, , 1998(Arkoosh et al, , 2001Varanasi et al, 1993;Casillas et al, 1995Casillas et al, , 1998, as well as biochemical alterations such as DNA damage (i.e., PAH-DNA adducts in liver) and induction of cytochrome P4501A (CYP1A), an enzyme that metabolizes selected contaminants including PAHs, dioxins and furans, and dioxin-like PCB congeners McCain et al, 1990;Varanasi et al, 1993;Collier et al, 1998;Stehr et al, 2000). These biochemical alterations are not necessarily indicative of adverse health effects in themselves, but are associated with disease conditions including reproductive and developmental abnormalities and liver disease (Williams et al, 1998;Whyte et al, 2000;Myers et al, 2003).…”