Manville on Asbestos: What did it know and when did it know it? An Easy way to Find Out.

Welcome to my 38th Blog since we started going down this path during December 2020. I very much appreciate all of your support, and I plan to continue my postings to educate those readers who are interested in the history of asbestos. After all, unless you understand that history, how could you hope to make heads or tails out of the present?

Today, we are going to take Johns-Manville at its word. That word, however, is the Johns-Manville Asbestos Knowledge Chronology which it created in the 1980s. In particular, this Blog will focus on the snippet from 1898 to 1933, which constitutes the first six pages of the chronology.

To be clear, the chronology is not one sided or self serving. Rather the entries seem factual. As an example for page 1, it states:

1898    Plantworker Risk. H.W. Johns, founder of J-M predecessor, dies on February 8, 1898, supposedly of asbestosis.

1902    Plantworker Risk.  British designate asbestos dust as potentially injurious to workers

So, taken at its word, the British knew as early as 1902 that asbestos dust was potentially injurious to workers. In addition, take a look at the other entries into 1930. Respirators were already considered by 1930 as a very good idea to help against the disease first named “asbestosis” as of December 3, 1927.

On page 2, I find particularly interesting the 1930 entry about the Merewether Report in which Merewether finds a dose relationship for chrysotile but the U.S. industry dismisses it while claiming it to be based on Amosite.

Page 3 primarily concerned plant conditions and medical knowledge from 1931 and 1932 including the Konocide Club for doctors which I had not heard of before. Take a read.

Take a look at the above entry on page 3 as continued to the below entry on page 4 from 1932 concerning lung x-rays. 61% lung abnormality as of 1932.

Page 5 discusses 1932 in terms of plant conditions with a heavy discussion on the use of respirators.

Page 6 for 1932 and 1933 starts adding in the discussion of customer risks, including recommending that “warnings should be posted regarding the dangers of dust exposure.”

I do not have all of the underlying documents as referenced in the chronicle, but they should be available from the Manville Trust Document Repository based in Denver, Colorado. You just have to ask and pay their fees. Please note their Internet URL at https://mantrust.claimsres.com/documents/.

As always, please email me with any questions at TheAsbestosBlog@gmail.com or leave a comment. I hope that you found this information interesting and useful. Also, let me know if you would like a complete copy of the chronology for your personal files. Marty