“…Recent studies have also shown an increase of highly carboxylated porphyrins (HCP, i.e., sum of uro-, hepta-, hexa-, and pentaporphyrin) in wild birds from the Great Lakes (Fox et al, 1988;Kennedy and Fox, 1990). A similar result has been found in pike (Esox lucius) from the Rhine River, heavily contaminated by hexachlorobenzene, hexachlorobiphenyl, DDT, and DDE (Koss et al, 1986). Furthermore, a dose-response relationship between exposure to hexachlorobenzene and levels of HCP in rats has also been reported (Kennedy and Wigfield, 1990).…”