Evaluation and comparison of the levels of occupational exposure to cobalt during dry and/or wet hard metal sharpening. Environmental and biological monitoring.

To investigate risks to hard metal tool sharpeners, 80 factories in the Lombardia Region (North Italy) were selected and examined. The scope of the survey consisted of verifying and quantifying that risk, so as to be able to control it and reduce it as far as is possible. We singled out a group of 12 factories, comprising approximately 750 workers 60 of whom were exposed to cobalt, in which operations such as sharpening with diamond grinding stones are normally carried out. In those factories, the risk was quantified by determining the concentration of cobalt in dust, collected by means of personal and fixed samplers (23 measurements) during sharpening operations. The station had no local ventilation device; sharpening is mainly performed wet and has been found to present a greater risk than those where sharpening is exclusively performed dry. Results were confirmed by biological monitoring which showed the presence of cobalt excreted in exposed workers' urine collected at the end of the work shift.

Occupational exposure to metallic cobalt in the Province of Bergamo. Results of a 1991 survey.

The results of a survey on workers potentially exposed to cobalt in the Bergamo Province are reported. Its aim is to assess the number of workers at risk of developing respiratory disease due to the inhalation of metallic cobalt. Interest was shown after an examination of 11 cases of 'hard metal disease', which we diagnosed, in workers who came from different production areas and had different degrees of exposure. A first group of 45 factories with potential cobalt exposure was identified by consulting the archives of the Local Sanitary Units (USSL) and of the Chamber of Commerce, and by use of the telephone directory and requesting information from the producers and users of Widia tools. A second group of 2039 factories was selected from those industrial activities where we had previously ascertained the presence of grinding operations using hard metal tools with diamond wheels. This study is related to all the factories in the first group and 10% of the factories in the second group. More than 304 inspections were carried out. In this context 403 exposed workers were identified. Workplace air measurements (250 samples) and biological monitoring (> 600 samples) to determine the exposure levels to cobalt were performed. The results show an unexpected diffuse occupational exposure in different production areas where the airborne cobalt is frequently underestimated and higher than the TLV.

[Health surveillance of workers]. / La sorveglianza sanitaria dei lavoratori.

The main purposes of the health surveillance of workers exposed to anaesthetic gases are: a) the finding of disorders either reliable to the exposure or incompatible with the activity in the operating theatre; b) the epidemiological evaluation of the late effects. Simple and rigorous methods to estimate the previous and the current risk are suggested. The main data to be collected during the medical examination are indicated. The registration of the data of the reproductive function by a protocol of recording is proposed. For the health surveillance of workers in Health Care Institution it's advisable to establish an interdisciplinary group, referring to a specialist on occupational medicine.