Surface physico-chemical studies of chrysotile asbestos and related minerals

Our plain-English summary of Surface physico-chemical studies of chrysotile asbestos and related minerals, by C. Jolicoeur, D. Poisson (Drug and Chemical Toxicology, 1987).

The study

• Authors: C. Jolicoeur, D. Poisson
• Journal: Drug and Chemical Toxicology
• Published: 1987;10(1-2):1-47
• Type of article: Review
• Read it: PubMed · Publisher

In plain English

This article was a review in a monograph on asbestos. The authors surveyed laboratory methods for studying the surfaces of chrysotile asbestos and related minerals, and published findings from them. The methods included chemical leaching, surface spectroscopy, gas and solution adsorption, chemical modification of fiber surfaces, and 'probe' molecules. The authors also reported preliminary results from their own laboratory. They treated chrysotile fibers with heat or with chemicals such as phosphorus oxychloride and organochlorosilanes. They then measured how much the fibers damaged red blood cells in the test tube (hemolysis), using a single dose for 60 minutes. Most surface treatments reduced hemolysis. In a preliminary table on ultra-short chrysotile fibers, untreated fibers caused 91% hemolysis. Phosphorus oxychloride-treated ultra-short fibers caused 6%. Silane-treated fibers still caused 10% and 27%. The authors stated that their limited results did not yet warrant generalization. They added that the results supported the idea that electron-donor sites on the fiber surface could play a role in chrysotile's biological activity. They noted that the link between such test-tube results and long-term disease can be questioned. Their preliminary experiments measured test-tube cell damage, not disease outcomes in people or live animals.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Review of laboratory (physico-chemical) research on mineral fiber surfaces, with some preliminary original in vitro results from the authors' laboratory
• Who was studied: Chrysotile asbestos and related minerals studied in published laboratory work. In the authors' own experiments: chrysotile fibers (described in Table 3 as ultra-short) that were native, heated or chemically treated, tested on red blood cells in vitro
• Exposure: Chrysotile fibers that were untreated, heated to 300°C, or reacted in the gas phase with chemicals including phosphorus oxychloride (POCl3) and organochlorosilanes. Hemolytic activity was measured after a single dose for 60 minutes.
• Main results:
  • In the authors' tests, most adsorbed or chemically reacted species on chrysotile fibers reduced the fibers' hemolytic activity
  • Heating chrysotile to 300°C reduced both the surface density of electron-donor sites and the hemolytic activity by approximately 20%
  • In the authors' preliminary Table 3 on ultra-short chrysotile fibers, the printed values for electron-donor site density (sites per nm²) and percent hemolysis were: untreated 1.10 and 91; heated 300°C 0.791 and 74; POCl3 0.03 and 6; CH2CH-SiCl3 0.009 and 10; CH3-SiCl3 0.008 and 27
  • Treatment with organochlorosilanes virtually eliminated the fiber-TCNE electron transfer reaction but left fibers with significant remaining hemolytic activity
  • So far, the phosphorylated (POCl3-treated) fibers appeared most effective at minimizing fiber-membrane interactions
• The authors' conclusion: The authors concluded that their limited results did not yet warrant generalization, but supported the notion that electron-donor sites could play a significant role in the biological activity of chrysotile fibers. They also stated that their overview pointed to more problems than solutions.
• Limitations the authors state:
  • The results were limited and preliminary, and did not yet warrant generalization
  • The relationship of in vitro experiments to long-term toxicity from exposure can be questioned
  • Detailed interpretation awaits better understanding of whether surface species were adsorbed or chemically bound

Topics

The National Library of Medicine indexes this study under subjects our site covers: Chrysotile.

Medical terms in this study, explained in our Lexicon: Chrysotile.

Related studies

• Mineral particles of varying composition induce differential chemokine release from epithelial lung cells: importance of physico-chemical characteristics — J. Ovrevik, T. Myran, et al. (2005)
• A critical review of the biological mechanisms underlying the in vivo and in vitro toxicity of carbon nanotubes: The contribution of physico-chemical characteristics — H.J. Johnston, G.R. Hutchison, et al. (2010)
• How are the physical and chemical properties of chrysotile asbestos altered by a 10-year residence in water and up to 5 days in simulated stomach acid? — K. Seshan (1983)
• Morphological and chemical mechanisms of elongated mineral particle toxicities — A.E. Aust, P.M. Cook, et al. (2011)
• The ability of mineral dusts and fibres to initiate lipid peroxidation. Part I: parameters which determine this ability — M. Gulumian (1999)
• Surface reactivity in the pathogenic response to particulates — B. Fubini (1997)

Browse more research in Drug and Chemical Toxicology, or return to medical research.