Kary explored the risks posed by antibacterial chemical triclosan in Colgate Total toothpaste, in part by examining pages of Colgate-Palmolive’s Food and Drug Administration application that were kept private after the toothpaste’s 1997 approval. Bloomberg News asked scientists to review the previously undisclosed pages, summaries of scientific studies Colgate submitted as part of its new-drug application. The pages contained indications, the scientists concluded, of a potential health danger in one of America’s top-selling toothpastes. Studies contained in these pages reported delayed bone growth and premature births in animals exposed to triclosan. Colgate’s application dismissed these effects as incidental, in part because they didn’t increase with the dose. In the years since Total’s approval, as the pages remained out of public view, independent scientists have built a better understanding of chemicals that disrupt hormonal functioning. The size of the dose, researchers have found, bears less relation to developmental irregularities than when the dose occurs. Triclosan is among these endocrine disruptors — a class of chemicals that has been linked, more broadly, to endocrine-related diseases including cancers, low birthweight babies, early breast development in girls and undescended testicles in boys. Other research has linked triclosan to the growth of cancer cells and bacteria. In recent years, several manufacturers have removed triclosan from hand soaps, deodorants and other health-care products. Minnesota has banned it from most health-care products. Colgate stands by Total toothpaste’s safety and its role in fighting gum disease, which can progress to periodontal disease. The FDA has also stood by its approval of the application filed by Colgate. Kary’s article raises questions about whether the FDA did appropriate due diligence in approving Total 17 years ago, and whether its approval should stand in light of new research.
