I'm really no expert on the whole BPA thing, and I've read a lot of mixed research about it. I say "considered" toxic because of some of the research that has come out about it. I think ultimately we're not totally sure of the impact it has on health. There are quite a few studies done on this so far but none are particularly conclusive.

Here's one relating to cashiers: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4824622/

And a more generalized one relating to factory workers who produce products containing BPA (like thermal paper): https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5634705/

It seems the government of France is also taking a stance against the use of thermal paper in the EU. There have been some concerns about BPA levels in groundwater, too, but this would be from all sources of BPA that end up in landfills, not just thermal paper.

Calling it "highly" toxic might not be entirely accurate when compared to something like radium, but one of the issues with BPA is we're not entirely sure of the health impacts. As a hormone disruptor, it seems to manifest in undetectable ways (links to heart disease, infertility, etc.) so it may be hard to pin down the effects of exposure until enough historical data has been gathered.

According to Health Canada (my country) 92.7% of their sample population had BPA concentrations in blood, a number that actually increased in the 7 years after it was banned from consumer products. (https://globalnews.ca/news/3694669/bpa-blood-samples-common/)

I'm also not trying to call for an immediate ban on it or anything like that, but merely stating that creating more of it without solving this problem is probably not a great idea.