Definition of polychlorinated biphenyl in US English:

polychlorinated biphenyl

(also PCB)


  • Any of a class of toxic aromatic compounds, often formed as waste in industrial processes, whose molecules contain two benzene rings in which hydrogen atoms have been replaced by chlorine atoms.

    • ‘Although trained as a veterinarian, Miyata cut his teeth as an environmental scientist researching another toxic chemical, polychlorinated biphenyl, at the Osaka Prefecture Institute of Public Health.’
    • ‘Presumed modern substances, dioxins typically are byproducts of the production of industrial chemicals such as polychlorinated biphenyls and some pesticides.’
    • ‘Further tests discovered traces of some of the world's most toxic industrial chemicals, including polychlorinated biphenyls and dioxin, in Arctic wildlife.’
    • ‘With respect to chemical potency and brain impairment, we found that hydrogen sulfide and polychlorinated biphenyls caused the most abnormalities in brain function - an average of 15.’
    • ‘This is an important convention, as it provides for the safe disposal of persistent organic pollutants, including polychlorinated biphenyl.’


polychlorinated biphenyl

/ˌpälēˈklôrəˌnātid bīˈfenəl/