Here is a link about OTC flea products:
Flea and Tick Product Ingredients: What You Should Know : The Humane Society of the United States
From that site is this information:
The products
The NRDC's report lists flea- and tick-control products marketed under the following major brand names that have been found to contain OPs: Alco, Americare, Beaphar, Double Duty, Ford's Freedom Five, Happy Jack, Hartz, Hopkins, Kill-Ko, Protection, Rabon, Riverdale, Sergeant's, Unicorn, Vet-Kem, Victory, and Zema. To protect their pets and children, consumers should consult with a veterinarian before purchasing any over-the-counter (OTC) products