PCBs are long recognized as a concern for human health. They are linked to cancer and effects on the immune, reproductive and neurological systems. The suite of industrial chemicals was banned in the late 1970s after decades of use as insulators and stabilizers in electrical transformers, lubricants and many other industrial applications. Yet, people and wildlife are still exposed to the persistent pollutants. Rats that were exposed to these mixtures of persistent chemicals while developing in the womb and while nursing had impaired inner ear function and hearing loss as adults. The results confirm both rodent and human research that find PCB exposures can result in cochlear dysfunction and – importantly – extends this disruption to a mixture of PCBs and PBDEs.