Banned Scotchgard chemical still contaminating San Francisco seals
What makes perfluorinated chemicals (PFCs) so stubbornly persistent is that they contain fluorine bonds, which are the shortest and strongest of chemical bonds. These same characteristics make them popular with manufacturers as coatings because they repel oil and water, stabilize heat and act as leveling agents to ingredients in cookware, textiles, carpeting, paper and other products. 3M Company began selling Scotchgard made with PFOS in 1956. Nearly half a century later, after studies showed it was accumulating in human tissues, the company agreed to stop producing the chemical by 2002.