The record
Method J4-1 was reliable only to 0.5%, compared with the FDA methodology's claimed accuracy to 0.01%, meaning cosmetic talc products could contain asbestos below the 0.5% detectable limit.
Claim scope
THE central quantitative claim of the entire measurement-politics narrative, in a peer-reviewed PubMed-indexed source: a fiftyfold difference in detection limit between the industry method and the abandoned federal method. Also verified in this paper: the CTFA's adopted definition of cosmetic talc as “containing no detectable fibrous asbestos minerals”, and Pfizer's H. D. Stanley objecting in writing after a July 8, 1976 CTFA meeting: “I particularly object to the section . . . that reads – containing no detectable asbestos minerals.”
What this source does not establish
This 0.5%/0.01% comparison is the authors' characterisation of the two methods, not a quotation from either method document. The 0.01% figure follows from the FDA's 99.99% chrysotile specification; the 0.5% figure is asserted for J4-1. Independent corroboration of the ORDER of the claim comes from McNeal: the CTFA's own December 1973 review recorded TEM+ED as capable of 0.1% detection, and Pfizer wrote in February 1977 that its method identified chrysotile at 0.5% and fibrous amphiboles at 0.1%. So contemporaneous documents place better-than-J4-1 sensitivity in the 0.1-0.5% range. Do NOT present 0.5% vs 0.01% as a document-quoted pair.
Limitations
MANDATORY DISCLOSURE whenever this paper is cited: its own conflict-of-interest statement reads “David Rosner and Gerald Markowitz wrote a 2017 Report to the Court in a legal case that formed the original basis of this article. They received funding from plaintiffs' law firms for research and writing.” Its documentary base is litigation-discovery material hosted on toxicdocs.org. It is peer-reviewed and PubMed-indexed, which satisfies house citation standards, but it is not a neutral archival study. Where the page wants a numeric contrast, the safest formulation is the FDA's own proposed 99.9%/99.99% specification (dual-sourced) against the industry's rejection of TEM at 0.1% capability (McNeal, quoting the CTFA's own document). Those two numbers are both document-quoted.
Source
Pmid — 31095409