Toxicity and metabolism of 4-n-nonylphenol in cell suspension cultures of different plant species

4-Nonylphenol, a metabolite of nonionic surfactants, is a compound of environmental concern due to its aquatic toxicity and estrogenic effects. The phytotoxicity of 4-n-nonylphenol was tested in 14 different cell suspension cultures. Except for carrot cells, 4-n-nonylphenol was toxic to all plant cells tested. The concentration causing 50% growth reduction in cell suspension cultures differed between plant species and ranged from 0.05 to more than 1.00 mM. The metabolism of 4-n-nonyl[U-C-14]phenol was investigated with cell suspension cultures according to a standardized test procedure (Langebartels, C.; Harms, H. Angew. Bot 1986, 9, 113-123). The distribution of radioactivity in fractions was dependent on the incubation time, dose, and plant species tested. Every plant species in cell suspension culture exhibited a unique metabolic behavior with respect to quantitative and qualitative parameters. However, there were similarities among taxonomically related plant species. There is evidence that the tolerance to 4-n-nonylphenol is correlated with the formation of nonextractable residues. Nonextractable residues were characterized with respect to the cell wall fractions containing radioactivity. With 7 of 12 cell cultures, lignin was the main fraction with radioactivity.