Binding of environmental carcinogens to asbestos and mineral fibres

Our plain-English summary of Binding of environmental carcinogens to asbestos and mineral fibres, by G. Harvey, M. Pagé, L. Dumas (British Journal of Industrial Medicine, 1984).

The study

• Authors: G. Harvey, M. Pagé, L. Dumas
• Journal: British Journal of Industrial Medicine
• Published: 1984;41(3):396-400
• Cited by: 16 articles, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text

Abstract

A rapid method has been developed for measuring the binding capacity of asbestos and other mineral fibres for environmental carcinogens. Benzo(alpha)pyrene (B(alpha)P), nitrosonornicotine (NNN), and N-acetyl-2-aminofluorene (NAAF) were assayed in the presence of Canadian grade 4T30 chrysotile, chrysotile A, amosite, crocidolite, glass microfibres, glasswool, attapulgite, and titanium dioxide. Chrysotile binds significantly more carcinogens than the other mineral fibres. This binding assay is reproducible with coefficients of variation of less than 8% and 6% respectively for inter and intra assay. The influence of pH was also studied, and there is good correlation between the carcinogen binding and the charge of the tested mineral fibres. The in vitro cytotoxicity on macrophage like cell line P388D1 and the haemolytic activity of various mineral fibres were also measured; a good correlation was found between the binding capacity and the cytotoxicity of tested mineral fibres on P388D1 cells. These results give some explanations for the reported synergism between exposure to asbestos and the smoking habits of workers.

In plain English

This was a laboratory study, done at Université Laval in Quebec, of how strongly different mineral fibres hold on to three cancer-causing chemicals: benzo(a)pyrene, nitrosonornicotine and N-acetyl-2-aminofluorene. The authors tested two samples of chrysotile asbestos (Canadian grade 4T30 and UICC chrysotile A), amosite, crocidolite, glass microfibres, glasswool, attapulgite (a fibrous clay) and titanium dioxide. Chrysotile bound significantly more of the chemicals than the other materials (p less than 0.005), except attapulgite, which bound as much as chrysotile. The authors also measured how each material changed water acidity, how much it damaged sheep red blood cells, and how toxic it was to a line of macrophage-like cells. Chrysotile and attapulgite were the most toxic to the cells, and titanium dioxide and crocidolite were also toxic. Titanium dioxide, glasswool, crocidolite and amosite caused negligible red blood cell damage. The authors reported a good correlation between chemical binding and the other tests. No people or animals were studied. The authors concluded that the results give some explanations for the reported synergism between asbestos exposure and smoking in workers.

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: In vitro laboratory experiment: binding of radiolabelled carcinogens to mineral fibres, with tests of effect on water pH, haemolysis of red blood cells, cytotoxicity to a cell line, and surface area, and correlations between these tests
• Who was studied: Mineral fibre samples (no human or animal subjects): Rhodesian chrysotile A, crocidolite and amosite from UICC; Canadian grade 4T30 chrysotile and attapulgite from IRDA; glass microfibre, glasswool and titanium dioxide from Fisher Scientific. Tests used sheep red blood cells and the macrophage-like cell line P388D1. Work done at the Department of Biochemistry, Université Laval, Quebec.
• Exposure: Three radiolabelled carcinogens (benzo(a)pyrene, nitrosonornicotine, N-acetyl-2-aminofluorene) mixed with suspensions (2 mg/ml) of chrysotile (4T30 and UICC A), amosite, crocidolite, glass microfibres, glasswool, attapulgite and titanium dioxide
• Main results:
  • Chrysotile bound significantly more of the carcinogens than the other mineral fibres (p less than 0.005), except attapulgite, which bound as much as chrysotile
  • Adding fibres to deionised water raised the pH, especially for chrysotile and attapulgite
  • Titanium dioxide, glasswool, crocidolite and amosite caused negligible haemolysis (red blood cell damage)
  • In the cell toxicity test, chrysotile and attapulgite were the most toxic fibres; titanium dioxide and crocidolite were also toxic
  • On a relative scale of 1.00 to 5.00, 4T30 Canadian chrysotile scored 2.44 for haemolysis and 5.00 for toxicity
  • The authors reported a good correlation between carcinogen binding capacity and all the other tests
  • Surface area correlated with binding of nitrosonornicotine and N-acetyl-2-aminofluorene and with toxicity, but its correlation with the other tests was not significant
• The authors' conclusion: The authors concluded that the results give some explanations for the reported synergism between asbestos exposure and the smoking habits of workers

Topics

Medical terms in this study, explained in our Lexicon: Chrysotile, Amosite, Crocidolite, Palygorskite (Attapulgite), Macrophage, Habit.

Related studies

• Influence of crystallization habit of minerals on in vitro cytotoxicity — L.D. Palekar, C.M. Spooner, et al. (1979)
• Benzo[a]pyrene uptake into rat liver microsomes: effects of adsorption of benzo[a]pyrene to asbestos and non-fibrous mineral particulates — J.R. Lakowicz, D.R. Bevan (1980)
• On the mechanism of cogenotoxic action between ingested amphibole asbestos fibres and benzo[a]pyrene: II. Tissue specificity studies using comet assay — C. Varga, G. Horváth, et al. (1999)
• Morphological transformation of Syrian hamster embryo cells induced by mineral fibres and the alleged enhancement of benzo[a]pyrene — S.O. Mikalsen, E. Rivedal, et al. (1988)
• The ability of mineral dusts and fibres to initiate lipid peroxidation. Part I: parameters which determine this ability — M. Gulumian (1999)
• Consensus on synergism between cigarette smoke and other environmental carcinogens in the causation of lung cancer — A.E. Reif, T. Heeren (1999)

Browse more research in British Journal of Industrial Medicine, or return to medical research.