[Potential exposure to carcinogens in low-melting alloys processing]

The objective in our study was to evaluate the worker's exposition to lead and cadmium in 32 radiology technicians in an eastern Sicily hospital in workers of low melting point alloy of lead, tin, cadmium and bismuth (league that can be melted at 73 degrees C as CERROBEND). Such alloy is used for the fabrication of objects used for the personal protection of cancer patients subject to high energy treatment. The parameters taken into consideration for this study were sex, age and smoking habits. In the test subject's working cycle reported in our case, there were traces of smoke formation containing lead, tin, bismuth and cadmium. Cadmium is a substance considered by IARC to be cancerous and can be found in both work and living environments, therefore it is often difficult to establish rather its presence in the organism is due to working activities and/or the living environment. In these cases it is necessary to evaluate whether the work represents an added risk to develop neoplasia, compared to the consequences due to normal environmental exposure. The added risk linked to work is evaluated comparing the concentration of toxic substances found in the living environments (Environmental Reference Value) with the toxic and/or metabolite found in the working environment, and comparing the biological reports of the population not directly exposed by work (Biological Reference Value) and those exposed. We performed a biological monitoring for lead and cadmium on the workers examined. The Italian Legislature, aside from lead, has not yet issued guidelines pertaining to professional exposure to cadmium, and therefore it is mandatory to take reference to the American Hygienist's charts both for environmental exposure (TLVs) andfor biological monitoring (BEI). Biological monitoring, which allows to evaluate the absorption by both inhalation and gastrointestinally, was performed through measuring the levels of lend and cadmium in the bloodstream (PbB and CdB) and the Cd in urine (CdU). The results show that in no case the levels of lead in the bloodstream (PbB) were above the reference value and BEI. The levels of cadmium urine (CdU) weren't above the reference level and the BEI, while the haematic levels of cadmium (CdB) were higher than the reference value in 8 subjects, each long time smokers, each of about 20 cigarettes a day. This data shows how, in the evaluation of exposition to cadmium, aside from the exam of data pertaining to work, the study of ways of absorption and the interpretation of the results of environmental and biological monitoring, it is important to consider the possibility of intoxication outside of the workplace. Cigarette smoke, as already indicated by other authors, is also confirmed in our studies as one of the major fonts of non professionally linked inhalation of cadmium.