This can cause pressure to build up in the veins, eventually causing them to burst. When this happens, you may vomit blood or ...

Discover the top causes of black poop like diet, supplements, and gut health conditions, plus the best treatment options ...

If someone has recently consumed any of these and their stool is black, there is likely no cause for concern. However, bleeding in the gastrointestinal tract can also cause black, tarry stools.

(AP) — The U.S. Coast Guard has been searching for tar balls that began showing up on South Florida beaches over the weekend, but so far the source of the black muck remains a mystery.