Something similar happened to a buddy, well, ex-buddy.....gassed himself...
ANYWAYS,
welding the bright iron one day, Aluminum, in tennis shoooooes, he commenced to dropping molten AL down his shoe top at the ankle.
If anyone knows what happens when you drop the tiniest amount of molten AL on the floor, it immediately turns into silver dollar sized flat pancaked pieces.
Well, that's what happened to that rather large drop of molten AL that went into that tennis shoe.
AN instant flash burn the size of a coke can top to the meat.
AND the AL stuck to the meat to be pulled away!
THAT was aweful to smell and see.
It took months to heal and remain infection free.