I have a digital thermometer with a probe. The probe is stainless steel but the cable and probe housing are apparently made of PVC. In my last brew I just submerged the whole probe in the boiler before the grain steep and left it there until I had cooled the wort. It was a 75m boil.
It's occurred to me now that this was a really stupid idea. The thermometer still seems to be working ok but I'm worried that chemicals will have leached into the beer. Should I throw the beer out or drink it? I can't really find any useful info on whether PVC is toxic under those circumstances.
UPDATE ON THIS Thanks very much for your answers. In the end I opted to throw out this batch. I expect it would have been perfectly fine but I don't want to be sitting there with cancer in twenty years wondering about it.