Controversy – Bassin study on the link between fluoridation and osteosarcoma

2001 – Elise Bassin completes her PhD thesis at Harvard Dental School, under the supervision of Professor Chester Douglass. Her thesis was an investigation of a possible relationship between exposure to fluoride and osteosarcoma. She discovers that if males are exposed to fluoride in their sixth to eighth years, their risk of osteosarcoma by the age of 20 is increased five to seven times. Bassin successfully defends her thesis and gains her PhD, even though her findings contradict those of Douglass’s research in 1991. The implications of Bassin’s study for the tens of millions of people living in fluoridated areas are apparent – the fluoride added to their water could be putting their young boys’ health and lives in serious danger. However, Bassin’s findings are not published or reported to the scientific community or the public.

2002 – Douglass attends a British Fluoridation Society meeting. At this meeting, as at other professional meetings, he does not alert his colleagues to Bassin’s findings.

2004 – Douglass testifies to the National Research Council (NRC) that he has not found evidence to indicate that fluoride is linked to osteosarcoma. In his testimony, he cites Bassin’s study. He gives no indication that its findings are in direct contradiction to his assertion.

January 2005 – the Fluoride Action Network’s Michael Connett uncovers Bassin’s thesis in the Harvard Medical School’s Rare Books Room, following a tip off. Some four years after its completion, the research and its findings are made public.

June 2005 – the Environmental Working Group (EWG) files an ethics complaint against Douglass with Harvard and the National Institutes of Environmental Health Sciences, who provided significant funding to Douglass’s research. The EWG accuses him of misrepresenting Bassin’s study and raising questions about conflicts of interest. It emerges that  Douglass was editor-in-chief of the Colgate Oral Care Report and had worked as a consultant to Colgate, who manufacture fluoridated toothpaste, for the preceding ten years. Media outlets including the Wall Street Journal, NBC and Fox 25 Boston pick up the story.

May 2006 – five years after Bassin made her findings, they are published in the journal Cancer Causes and Control. Douglass responds to the study in a letter, which appears in the very same issue of the journal in which the study is first published. The letter urges that Bassin’s study be interpreted with “caution” and considered as a subset of a larger study. Douglass asserts that his findings in this larger study, “currently being prepared for publication” (that is, in May 2006), have not replicated Bassin’s.

August 2006 – in a four paragraph statement, Harvard clears Douglass of misconduct. The statement does not give reasons for the findings of the review.

2008 – Douglass retires from his chairmanship of the Department of Oral Health Policy and Epidemiology at the Harvard School of Dental Medicine. Chris Neurath and Paul Connett review the methodology for Douglass’s study, as outlined in his letter of May 2006 and discover that this methodology cannot produce results that would refute Bassin’s findings.

August 2010 – Douglass’s study, referred to in his letter of May 2006, is presumably still “being prepared for publication” as it has not, to date, been published.

July 2011 – Douglass finally published his long-promised study. But it failed to even address age-related risk, let alone disprove it. As predicted, it just looked at bone-fluoride levels, which shows total lifetime exposure, not age-related exposure. It had serious methodological flaws, for example the control group had a median age of 41 compared with 18, and there was a serious imbalance in gender weighting. the study was also much smaller than Bassin’s; not larger as Douglass had promised.

Bassin’s study stands as the best sceince we have on the osteosarcoma-fluoride issue.