No abstract

The metabolism of 10 different congeners of polychlorinated biphenyls (PCBs) was tested in cell cultures of 12 different plant species. The rate of metabolism was determined through comparison with cells inactivated by treatment with perchloric acid. The metabolism of defined PCB congeners was strongly dependent on the plant species. In particular, two Fabaceae species exhibited high capacities for metabolizing different congeners. Except for PCB 15 (4,4′‐dichlorobiphenyl), it was shown that a lower chlorination grade is associated with higher metabolism rates. Also, it was shown that substitution and molecular configuration play an important role in the metabolism of PCBs in plants. In studies with 14C‐PCB 1 (2‐chlorobiphenyl) in soybean cultures, one dihydroxylated and six different monohydroxylated compounds were detected after acid hydrolysis of polar metabolites (conjugates). Hydrolysis of metabolites of 14C‐PCB 52 (2,2′,5,5′‐tetrachlorobiphenyl) in wheat cell cultures yielded four monohydroxylated and three dihydroxylated metabolites.