Food web transfer ofPAH metabolites is another area that has received little attention. Because many species can metabolize PAHs, it is generally assumed that trophic transfer and biomagnification (an increase in tissue concentration over two or more trophic levels) of these compounds is not important for food webs. Trophic transfer and biomagnification of PAHs is not expected for food webs involving vertebrates; however, species from the lower trophic levels that are not able to effectively metabolize these compounds may exhibit food web transfer if vertebrates are not involved. Even though parent PAHs may not be biomagnified, prey species may contain high levels of metabolites that could be accumulated by predators. A few studies have found that fish accumulate PAH metabolites after ingesting invertebrates that had metabolized these compounds. Because these metabolites can be very toxic, additional research examining bioaccumulation of PAH metabolites from ingested prey is very important for a complete understanding of trophic transfer and the potential for toxic effects.
Was this article helpful?