If everything does, then nothing specific can. That’s a way to protect real toxic offenders from liability. You say you got cancer from some particular environmental toxin, you name the source, and try to sue. “Remember the movie Erin Brockovich and Hexagonal Chromium”. The defense would say, you park your car in a ramp. There’s a posted notice. You pump your own gas. There’s a posted notice. Ergo you can’t isolate the defendant’s toxin as the sole cause of your disease. I’m not a lawyer. It just seems to me like a cleverly deployed lawfare smokescreen.