I. F. H. Purchase

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The mutagenic activity of vinyl chloride (VC) and vinylidene dichloride (VDC) at three exposure levels was assessed in fertile male CD-1 mice with the dominant lethal test. Each compound was assessed in a separate study. Male mice were exposed by inhalation to VC at 3000, 10,000, and 30,000 ppm and to VDC at 10, 30, and 50 ppm for 6 hr/day for 5 days. By(More)
Estimations of the incidence of hepatocellular carcinoma (HCC) for the period 1968-74 in the Province of Inhambane, Mozambique, have been calculated and together with rates observed in South Africa among mineworkers from the same Province indicate very high levels of incidence in certain districts of Inhambane. Exceptionally high incidence levels in(More)
Six short term tests for detecting carcinogenicity have been evaluated using 120 compounds, of which half were carcinogens and the rest non-carcinogens. The results obtained indicate that the Ames test and a "cell transformation" assay are both sufficiently sensitive to carcinogenicity, or the lack of it, in the compounds studied to enable them to be(More)
The carcinogenicity of 250 chemicals in 2 species, usually the rat and the mouse, was obtained from the published literature through 3 independent sources. Of the 250 compounds listed, 38% were non-carcinogenic in both rats and mice, and 44% were carcinogenic in both species. A total of 43 compounds had different results in the two species, 21 (8%) being(More)
A number of tests have been described which are thought to be capable of identifying carcinogens without using the actual induction of cancer as an endpoint. This study compared the performance of 6 such tests on a selection of 120 organic chemicals. The tests studies were: (1) mutation of Salmonella typhimurium; (2) cell transformation; (3) degranulation(More)
649 the book, effectively published in 1978, is at once 3 years out-of-date. I recently reviewred a multi-author symposium on the same topic. Dated 1976 and published early 1977: this contains more recent developments. In measuring tumour size, one sympathizes and agrees with the author's recommendation to accept classification by reference to the size of(More)
Groups of male and female beagle dogs were given daily doses of 400 mg of various mixtures of naphthylamines for up to 109 months. Survivors were killed at 128 months. A variety of pathological conditions was diagnosed, but the only effect related to treatment was the induction of bladder neoplasms. All dogs which received pure 2-naphthylamine developed(More)
Skin lesions have been identified in 20 workers manufacturing 4,4'-bipyridyl. The lesions were on the face, neck, and backs of the hands and arms. Larger localised lesions were removed surgically and examined histopathologically, but other lesions have been treated topically with fluorouracil cream. Histological diagnosis showed a progression from keratosis(More)