Hand-arm vibration syndrome and dose-response relation for vibration induced white finger among quarry drillers and stonecarvers

Objectives-To investigate the occurrence of disorders associated with the hand arm vibration syndrome in a large population of stone workers in Italy. The dose-response relation for vibration induced white finger (VWF) was also studied. Methods-The study population consisted of 570 quarry drillers and stonecarvers exposed to vibration and 258 control stone workers who performed only manual activity. Each subject was interviewed with health and workplace assessment questionnaires. Sensorineural and VWF disorders were staged according to the Stockholm workshop scales. Vibration was measured on a representative sample of percussive and rotary tools. The 8 h energy equivalent frequency weighted acceleration (A (8)) and lifetime vibration doses were calculated for each of the exposed stone workers. Results-Sensorineural and musculoskeletal symptoms occurred more frequently in the workers exposed to vibration than in the controls, but trend statistics did not show a linear exposureresponse relation for these disorders. The prevalence ofVWF was found to be 30'2% in the entire group exposed to vibration. Raynaud's phenomenon was discovered in 4*3% ofthe controls. VWF was strongly associated with exposure to vibration and a monotonic dose-response relation was found. According to the exposure data of this study, the expected percentage of stone workers affected with VWF tends to increase roughly in proportion to the square root of A(8) (for a particular exposure period) or in proportion to the square root of the duration of exposure (for a constant magnitude ofvibration). Conclusion-Even although limited to a specific work situation, the doseresponse relation for VWF estimated in this study suggests a time dependency such that halving the years of exposure allows a doubling ofthe energy equivalent vibration. According to these findings, the vibration exposure levels currently under discussion within the European Community seem to represent reasonable exposure limits for the protection of workers against the harmful effects of hand transmitted vibration. Adverse health effects resulting from the use of vibrating tools in the stone industry have been reported since the beginning of this century. In 191 1, Giovanni Loriga, an Italian physician, first described the occurrence of episodes of tingling, numbness, and whiteness in the fingers and hands of stone and marble cutters and carvers who used barrel shaped air hammers without a handle and throttle valve.' Later in 1918, Alice Hamilton reported that 89-5% of 38 limestone cutters of Bedford, Indiana, United States, had attacks of finger blanching (defined as "spastic anemia affecting the arterioles of the fingers and hands")2 resembling the digital ischaemic phenomenon described by the French physician Maurice Raynaud in 1862. A personal review of the available scientific literature showed that in the last 80 years about 20 epidemiological surveys of vibration induced disorders among stone workers have been performed. 1-12 Italy produces more stone than any other country in the world (7-2 million tons in 1991). In Italy great varieties of ornamental stones such as marble, travertine, porphyry, granite, and serpentine are excavated in the quarries and processed in the mills. In recent decades there has been limited implementation of technical measures aimed at reducing the risk from exposure to excessive vibration in the stone industry. Taylor et al who revisited the limestone quarries of Bedford after a 60 year interval,7 found that no change in the design of the air hammers used by the stonecutters had taken place since the 1918 Hamilton survey. We did similar observations in a previous study of travertine quarry drillers and stonecutters who mainly operated percussive pneumatic tools.'0 In the present study, the occurrence of hand-arm vibration syndrome was investigated in a large sample of quarry drillers and stonecarvers working in several districts of Italy. The term hand-arm vibration syndrome is used to refer to the collection of peripheral neurological, vascular, and musculoskeletal symptoms that are recognised to affect the upper extremities of workers exposed to vibration. As the characteristics of vibration exposure in the stone industry were found to be stable over time, mainly with respect to the type and design of the pneumatic tools used by the stone workers, the relation between vibration exposure and the various components of the hand-arm vibration syndrome was also studied. (Occup Environ Med 1994;51:603-61 1) Institute of Occupational Health, University ofTrieste, c/o Centro Tumori, Via delta PietA 19, 134129 Trieste, Italy M Bovenzi UO TSLL, USSL 21, Morbegno, Sondrio S Cerri SMML, USL Centro Sud, Bolzano A Merseburger SPISLL USL30. Siena L Scattoni I Pinto UO TSLL, USSL 58, Domodossola, Novara V Ronca SPISLL, USL 3, Pietrasanta, Lucca, A Nucci SMPIL, USL 28, Bologna S Mattioli ULSS 26, Bussolengo, Verona C Zanderigo Correspondence to: Dr Massimo Bovenzi, Istituto di Medicina del Lavoro, UniversitA di Trieste, c/o Centro Tumori, Via della Pietk 19, 1-34129 Trieste, Italy. Accepted 16 May 1994 603 group.bmj.com on June 25, 2017 Published by http://oem.bmj.com/ Downloaded from