This is actually a serious issue that’s ruining food supplies (particularly in the oceans). Farmed catfish in the USA has been noted for high levels of dioxins. US chicken often contained crazy levels of arsenic until agricultural practices changed to avoid that. Broth made from bones often contains more lead than the daily allowable intake (something like 475% more in the case of broth made with chicken bones, skin, and cartilage present, but still far too much when using just the meat).
We are exposing ourselves to dangerous substances every day due to bioaccumulation in animal foods.
See https://en.wikipedia.org/wiki/Biomagnification