Hi clare and allI'm not sure whether the story of somebody dying through over exposure to thermoform is true, but I wouldn't be surprised if there are carcinogens in the plastics - if not nowadays, perhaps in the past.
Like some of you, I still have my carol book of thermoform sheets. I even kept my geography maps of South America and Australia. The rest of my form thought I was mad for keeping the maps, but I still look at them occasionally. The staff at school were much better at producing maps than the RNIB. I can remember one teacher even using it to create a picture from The Little Prince, and one to show us the Greek letters.
Way before braille embossers, a lot of the books from the prison braille transcription units were issued in thermoform and I also remember receiving a few from the students' library.
Linda