[Correlation between exhaled benzene and environmental exposure in refinery workers].

Benzene is still present in various working processes. Many methods are available for the biological monitoring of benzene exposure. The Authors present a study concerning a series of 23 workers of a refinery exposed to benzene.

[Three cases of pleural mesothelioma and environmental pollution with tremolite outcrops in Lucania].

In a circumscribed rural area of Lucania (Italy) three cases of pleural mesothelioma have been identified: two men, 83 and 52 years old and a 78 year-old woman, who all had in common the fact of being shepards in that area. Possible asbestos pollution sources have been sought: we have immediately excluded an asbestos manufactured articles pollution, however we have highlighted the presence of "green stones", which had always been known to the local inhabitants and which, in three subsequent campains of collecting and chemical-mineralogical investigations, have resulted partly constituted by amphibole asbestos, classified as tremolite. Official institutions are organising a series of initiatives to verify the hypothesis of a causal relationship between the presence of tremolite and the cases of pleural mesothelioma, and preventive initiatives aimed at reducing exposure and to a sanitary surveillance.

[Reduction of lubricating-oil aerosol concentration in the weaving room].

In this work the authors describe a weaving work room where they had determined particulate oil aerosol above TLV. The reduction of the oil aerosol has been obtained with the construction of an extraction and immission air suitable system.

[Gas chromatographic determination of biphenyl and 2-phenylphenol in the environmental air of dyeing-plant rooms of the textile industry].

A report is made on a method of sampling and analysis of biphenyl and 2-phenylphenol which are present in the environmental air of the dyeing plant rooms of the textile industry. The sampling is carried out by filtering environmental air through small pipes containing two layers of Porapak Q 80-100 mesh, the first one of 150 mg for the analysis and the other, of 50 mg, for the control, with a flux of about 1 l/min. The report includes the description of some tests concerning shifting and displacement with various fluxes, as well as the recovery of known quantities and the stability of the sampling.

[Asbestos minerals: their recognition and determination].

Fibers of amphibolic and serpentinic asbestos may be optically distinguished by the method proposed by the AA. The method is based on the observation at the microscope in reflected fluorescence of fibers of asbestos previously treated with a fluorochrome colouring agent; it can be applied for the individual counting of fibers on the filters used for checking the environmental air and has already been applied with good results in asbestic cement factories.

[Determination of weight concentration of dusts using automatic sample-collecting devices based on beta absorption and on the Tyndall effect].

Some automatic sample-collecting sets for measuring the ponderal concentration of dust have been tested. Such apparatuses are based on two different principles: beta ray absorption, and Tyndall effect. It is shown how, through the beta absorption apparatus, it is also possible to carry out absolute measurements, after evaluating obviously the possible matrix effects.

[Determination of free crystalline silica in atmospheric dust].

The method for the determination of free crystalline silica (quarts), as previously described by two of the authors, has been employed on atmosphere dust of unconfined spaces. The matrix effect of atmospheric dust has been investigated in winter and in summer. The limits in the use of this method have been studied considering also what stated by law code n.