David Egilman, rebutting a defence of asbestos industry financed scientist David Bernstein’s work by UK professor Ken Donaldson, points out the standard protocol for testing fibres for carcinogenicity in humans is a two-year animal inhalation study – not a five-day study of the sort overseen by Bernstein. Bernstein has used the test to argue chrysotile was less “biopersistent” so less harmful. Although the two-year test was endorsed by an expert government panel – of which Bernstein was a member – in the mid-1990s, Bernstein decided the five-day test would suffice. Egilman, a Brown University professor who has been an expert witness for asbestos plaintiffs, noted “the key question is… do the fibres persist long enough to induce the disease (eg. induction of mutations when cancer is the outcome of interest)? The answer to this question is clearly yes.”

K Donaldson, G Oberdorster. Continued controversy on chrysotile biopersistence, International Journal of Occupational and Environmental Health (IJOEH), volume 17, number 1, pages 98-99, 2011; and rebuttal by David Egilman pages 99-102.