Just wondering did she only test her own Tupperware or a big cross section? May be they were used for measuring paint or something in the past and had traces of residue left in them? If it was only found in measuring cups this is more likely as the factory would make all Tupperware with the same plastic so it is highly unlikely they would use a different composition for making only the measuring cups. As they are old they would have had many things ensured in them over the years.
Published 17th February 2020