Cluster of malignant mesothelioma cases in a thermostat manufacturing industry

La Medicina del Lavoro. 2006 Nov-Dec;97(6):774-8. [Link]

Aiani MR, Settimi L, Festa R, De Stefani M, Mensi C.

Servizio Prevenzione e Sicurezza negli Ambienti di Lavoro (SPSAL), ASL Provincia di Como.


Background: Malignant mesothelioma is a rare disease and the identification of a cluster of cases suggests a possible presence of an asbestos contamination source.

Objectives: To describe 3 cases of malignant mesothelioma (2 pleural and 1 peritoneal) that occurred in workers employed in the same thermostat factory.

Methods: Since this occupational sector is not traditionally known for asbestos exposure the Lombardy Mesothelioma Registry proposed to Local Occupational Health Unit to investigate this industry.

Results: From the first inspection of the plant, an environmental asbestos contamination (ropes covering oven handle and gasket) was found. But the greatest source of exposure was identified in the melamine resin reinforced with asbestos that constituted some internal parts of thermostats and that were sheared and perforated by the workers. So the 3 cases were defined as occupational diseases and legal procedures were initiated.

Conclusion: The results underline the importance of a close cooperation within Local Occupational Health Units and Mesothelioma Registry in the identification and evaluation of asbestos occupational exposure otherwise not recognized, determining thus the loss of precious information.