 Between then and 1914, large amounts of PCBs were released into the environment, to the extent that there are still measurable amounts of PCBs in feathers of birds currently held in museums.In 1935, Monsanto Chemical Company (now Solutia Inc) took over commercial production of PCBs from Swann Chemical Company which had begun in 1929.PCBs, originally termed "chlorinated diphenyls", were commercially produced as mixtures of isomers at different degrees of chlorination.