RedactedNarrative: Operator was towing 2 tubers on a Air Head revolution tube when the injured fell off the tube. She was dragged by the line for a short distance and it caused injury.  The victim's dad was on shore and was watching what was occurring, jumped into his vessel and went over to where his daughter was in the water.  He jumped in held her head up and cut the tow line as he saw the hook was embedded.  The  investigator was unable to determine whether the hook was faulty or if there were any recalls on it. The tow line had been purchased years ago but the tube was just purchased 2 weeks ago.  It is not known how the hook became dislodged from the eye and embedded.  Investigator indicates that it appears that the operator was operating in a responsible manner prior to this incident occurring, there was a lookout and tubers were wearing life jackets.  No cause was determined except that it was an unfortunate accident.