How harmful is parquet glue to health when using underfloor heating?

Baufritz advertises that their own parquet adhesive contains no plasticizers whatsoever. However, you cannot buy it (i.e., without the house). The thing is, Baufritz surely doesn't mix it themselves. With some research, you might find out which manufacturer it comes from. Alternatively, on the website of the quality label [Blauer Engel], you can find some products, e.g., from Bostik or Mapei, that are declared as "without plasticizing ingredients." For example, "Bostik WOOD H770 ECO PREMIUM." Whether it's any good, I can't say though. :)

Solvent-free and plasticizer-free options are available from various manufacturers. I have been using adhesives from Bona for years – a solvent-free variant with the Emicode EC1 PLUS label. The label is for products that operate at the technical limit of what is possible ==> very low emissions.

I think Blauer Engel is to be considered about as reputable as a foundation that tests things (in the sense of not at all, because purchased/limited evaluation)?

And in some areas, limit values are allowed in Germany that are unthinkable in other countries. I can’t quite put it together anymore, but maybe formaldehyde was involved.

Titanium dioxide has only recently been on the (suspected?) list of carcinogenic substances in Germany. It is contained in every paint with the white cat or other paints, while it has long been banned in other countries.

It’s a science and can drive you quite crazy...

I was not aware that Stiftung Warentest is "bought". Do you have sources for this thesis?
No offense intended, I'm really interested!

No sources, hearsay, therefore changed above.

But for example with dog food, the dilemma is: Yes, the tests were correct in that packaging and ingredients were examined and the ingredients listed were in it --> full score. But whether these ingredients are healthy for animals, no one has investigated. Consequently, an uninformed dog owner buys from the discount store because "It's the test winner at the foundation," but feeds their dog more or less grain mush with meat flavor.

like Stiftung, which tests things (in the sense of not at all, because bought/limited evaluation)?

I was not aware that Stiftung Warentest is "bought". Do you have sources for this claim?

So, as someone who works at a company whose products are also regularly tested by the Stiftung, I can say that the test results are not bought. As far as I know, it is not directly influenced by the company whose product is tested or by sending specially prepared test samples. They are ordered just like anyone else.
What is bought is the license to use the test seal for advertising purposes.
The significance of the test results or the test methods may, depending on the product, indeed be questionable, but that is another matter.