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Quantification of Violacein in Chromobacterium violaceum and Its Inhibition by Bioactive Compounds
Published on: August 8, 2025
[Pier Luigi Viola and vinyl chloride: notes that were never published]
1Osservatorio Epidemiologico, Direzione Generale Saniti, Regione Lombardia, Milano. carlo_zocchetti@regione.lombardia.it
Abstract:
The name and work of Pier Luigi Viola (1917-1985) are unequivocally connected with the history of the discovery of the toxic effects of vinyl chloride, cancer in particular. A biography and a bibliography of Professor Viola are still lacking but his work is well documented; equally well known is his professional career as an occupational physician who spent his entire working life as an employee of one single industrial group, Solvay; his work was dedicated firstly to taking care of the health of the workers of the Corporation and not only in Italy, and secondly to organizing the occupational health departments of all Solvay's establishments in Italy. This positive connection between occupational physician and scientist has recently been challenged in certain historical reconstructions of the discovery of vinyl chloride's carcinogenicity: in particular, these reconstructions (which we do not consider to be coherent with the facts) depict Viola as in constant conflict with his employer. As crucial support to this view are offered on the one hand a statement by Viola, in 1980, that "At the basis of every discovery there is frequently the poetical imagination of a researcher who is always alone in facing the difficulties of the research, difficulties that rise up against him like a wall reaching up to the sky"; and on the other the supposed failure to find some of Professor Viola's notes which should reflect his spiritual testimony, and from which should emerge "the suffering, the torments, and the pressures of that initial period". The true history is very different: the notes do exist: they were personally delivered to one of the authors (PB) by Viola's widow a few months after his death; they are in fact the first pages of a planned book on vinyl chloride that Viola never actually succeeded in writing. In these pages Viola developed some personal reflections from which it is clear that he was conscious of having been in the centre ofa fantastic adventure in the field of scientific research in which he also played the principal role; there is no mention whatsoever of any conflict or contrast between Viola and Solvay. In fact, the backdrop to this story reflects the typical dynamics of scientific research. The article continues with the publication of Viola's handwritten notes: in this way the supposed "mistery of the missing notes" is solved.
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