The agency is advising people to avoid misusing or inhaling the products that are marketed as whipped cream chargers but have been used as recreational drugs.
Mr. Kennedy told executives of major food companies that he wants synthetic colors removed from their products. “Decision time is imminent,” a trade group warned its members.
At a hearing, Dr. Marty Makary, the nominee for F.D.A. commissioner, fielded questions focused on whether he would review or reopen certain policy areas.
Dr. Marty Makary will testify before the Senate health committee on Thursday. Lawmakers may press him over staff reductions and changes in agency direction on issues like vaccines.