Mesotheliomas among Machinists and Other Railroad Workers

Asbestos exposure has been the culprit behind many deaths among blue collar workers.?? If we are ever going to find a cure, then we all must support the financing of continued research.?? One interesting study is called, "Mesotheliomas due to asbestos used in railroads in Italy" by Maltoni, C, Pinto, C, Mobiglia, A - Annals of the New York Academy of Sciences [ANN. N.Y. ACAD. SCI.]. Vol. 643, pp. 347-366. 1991.?? Here is an excerpt: "The available knowledge of the oncogenic risks of asbestos, the presentation of some data on the uses of asbestos in railroads, with particular regard to the Italian State Railroads (Ferrovie dello Stato = FS), and the identification of groups at risk because of exposure to asbestos used in railroads are briefly reviewed. The available data in the literature on the pathologic effects of such exposure, and in particular on the onset of mesotheliomas among machinists and other railroad workers, are also summarized. Eighty-three cases, in various Italian regions, of mesothelioma (78 pleural, 4 peritoneal, and 1 pericardial) are reported that are related to the exposure to asbestos used in railroads. Twenty-six of these cases (among which 25 were reported in the Emilia-Romagna region) were submitted to a detailed study at the Bologna Institute of Oncology. Forty-nine cases of mesothelioma occurred among FS workers, in particular machinists."

Another interesting study is called, "Dimensions of airborne asbestos fibres." By Gibbs GW, Hwang CY. - IARC Sci Publ. 1980;(30):69-78.?? Here is an excerpt: "Abstract - Systematic measurements were made of the dimensions of fibres found in the air in mines and mills for crocidolite, amosite and chrysotile. Samples were collected on membrane filters and examined in light, transmission electron and scanning electron microscopes. The proportion of short fibres was shown to decrease with extent of processing, especially for amosite. No airborne fibres had a diameter greater than 3 micrometers, and all would therefore be capable of reaching the pulmonary alveoli. It was shown that for the same airborne mss of the different varieties of asbestos, fewer amosite fibres would be present than crocidolite or chrysotile fibres. Most of the fibres to which workers are exposed are short and thin. It was also shown that the choice of analytical method and the limits of fibre dimension that can be observed are critical. Thus, fibres greater than 5 micrometers which are visible in the light microscope represent only a small proportion of the total fibre count, and transmission electron microscopic methods can lead to under-reporting of long fibres."

A third study is called, "The influence of asbestos dust on the oncogenic transformation of C3H10T 1/2 cells." By Brown RC, Poole A, Fleming GT. - Cancer Lett. 1983 Mar;18(2):221-7.?? Here is an excerpt: "Abstract - The cell transforming ability of asbestos dust was investigated using C3H10T 1/2 murine fibroblasts. In a series of experiments both crocidolite and amosite caused no increase in the number of transformed foci over that seen in cultures from untreated cells. The dusts, were, however, capable of augmenting the oncogenic effect of benzo[a]pyrene (BP). This putative synergistic effect was evident when fibres and chemicals were added to cultures as simple mixtures and when BP was adsorbed to the surface of the fibres."

We all owe a debt of gratitude to these fine researchers for their important work.?? If you found any of these excerpts helpful, please read the studies in their entirety.