When I lived on the coast of South Texas from 82-87 there were always oil and tar balls washing up on the beach from the 1979 oil spill from the Ixtop rig Spend a day at the beach and before you go in the house you had to spend 20 minutes wiping tar off your feet, plus there was always so much junk washed up on the beach from industrial size bleach jugs to rusty cans. They were not items left from normal beach goers but dumped into the sea off oil rigs and cargo ships. It could really be disgusting especially after a storm.