“Sure enough … it was PCB oil,” said Cynthia Yost, who was among teachers who sent pieces of carpet and classroom air filters to a lab. Tests found elevated levels of the toxic chemicals, used as ...

Millions of fluorescent light ballasts containing PCBs probably remain in schools and day care centers across the U.S. four decades after the chemicals were banned over concerns that they could cause ...

This combination of images from April 28, 2014, and July 15, 2016, respectively, and provided by teacher Cynthia Yost, shows black residue from a failed fluorescent light ballast, left, and a carpet ...

Millions of fluorescent light ballasts containing PCBs probably remain in schools and day care centers across the U.S. four decades after the chemicals were banned over concerns that they could cause ...

Regulators also discovered that old fluorescent light ballasts remained a potentially widespread source of PCB contamination. The EPA had allowed the ballasts to remain in use because chemicals were ...

This combination of images from April 28, 2014, and July 15, 2016, respectively, and provided by teacher Cynthia Yost, shows black residue from a failed fluorescent light ballast, left, and a carpet ...