The transformation sequence of cement-asbestos slates up to 1200 degrees C and safe recycling of the reaction product in stoneware tile mixtures.

Cement-asbestos is the main asbestos containing material still found in most of the European countries such as Italy. Man- and weathering-induced degradation of the cement-asbestos slates makes them a source of dispersion of asbestos fibres and represents a priority cause of concern. This concern is the main prompt for the actual policy of abatement and disposal of asbestos containing materials in controlled wastes. An alternative solution to the disposal in dumping sites is the direct temperature-induced transformation of the cement-asbestos slates into non-hazardous mineral phases. This patented process avoids the stage of mechanical milling of the material before the treatment, which improves the reactivity of the materials but may be critical for the dispersion of asbestos fibres in working and life environment. For the first time, this paper reports the description of the reaction path taking place during the firing of cement-asbestos slates up to the complete transformation temperature, 1200 degrees C. The reaction sequence was investigated using different experimental techniques such as optical and electron microscopy, in situ and ex situ quali-quantitative X-ray powder diffraction. The understanding of the complex reaction path is of basic importance for the optimization of industrial heating processes leading to a safe recycling of the transformed product. For the recycling of asbestos containing materials, the Italian laws require that the product of the crystal chemical transformation of asbestos containing materials must be entirely asbestos-free, and should not contain more than 0.1 wt% fraction of the carcinogenic substances such as cristobalite. Moreover, if fibrous phases other than asbestos (with length to diameter ratio >3) are found, they must have a geometrical diameter larger than 3 microm. We have demonstrated that using an interplay of different experimental techniques, it is possible to safely verify the complete transformation of asbestos minerals in this temperature-induced process. The product of transformation of cement-asbestos (CATP) has a phase composition similar to that of a natural or a low temperature clinker with the exception of having a larger content of aluminium, iron and magnesium. This product can be safely recycled for the production of stoneware tile mixtures. The addition of 3-5 mass% of CATP does not bear significant variations to the standard parameters of white porcelain tile mixtures.

Acute pancreatitis after azathioprine treatment for ulcerative colitis.

Inflammatory bowel disease, in addition to intestinal involvement, may be complicated also by other extra-intestinal manifestations. Moreover, drugs commonly employed in the treatment of ulcerative colitis and Crohn's disease may induce iatrogenic pancreatitis. Acute pancreatitis is described in two ulcerative colitis patients following azathioprine treatment.

Dietary habits as risk factors for inflammatory bowel disease.

OBJECTIVE: To examine the influence of dietary factors in Italian patients with ulcerative colitis and Crohn's disease. DESIGN: We studied dietary habits immediately prior to the onset of disease in 104 patients enrolled in a prospective, epidemiological study of the incidence of inflammatory bowel disease in Italy. METHODS: Each patient was interviewed using a recall questionnaire to provide information on the daily intake of nutrients. The differences in diet between patients and healthy subjects matched for age, sex and city of residence were determined. RESULTS: Our data confirm that patients with Crohn's disease and ulcerative colitis have a high intake of total carbohydrate, starch and refined sugar. This resulted in a significantly higher relative risk (P < 0.001) in both ulcerative colitis and Crohn's disease patients. Total protein intake was significantly higher in ulcerative colitis, but not in Crohn's disease patients, than in controls. Fibre consumption did not differ between patients and controls. CONCLUSIONS: Our results confirm that carbohydrate consumption is significantly higher in IBD patients than in healthy controls. Ulcerative colitis patients also consumed more total protein than controls. The pathogenetic significance of these findings, however, remains unclear.