Mortality from Occupational Exposure to Relatively Pure Chrysotile: A 39-Year Study

Abstract

Background: Asbestos exposure is related to serious adverse health effects. However, there is disagreement about the relationship between chrysotile exposure and mesothelioma or lung cancer. Objectives: Our aim was to investigate the mortality rate among workers exposed to relatively pure chrysotile in an asbestos cement factory. Patients and Methods: In an asbestos cement plant opened in 1968, we prospectively studied all 317 workers. A quantity of 2,000 tons of chrysotile, with minimal amphibole contamination, was used annually until 1 January 2005. Asbestos fiber concentration was measured regularly. Date and cause of death were recorded among active and retired workers. Results: Asbestos fiber concentration was always below permissible levels. Fifty-two workers died during the study. The cause was cancer in 28 subjects; lung cancer was diagnosed in 16 of them. No case of mesothelioma was reported. Death was attributed to cardiovascular diseases in 23 subjects and to liver cirrhosis in 1. Overall mortality rate was significantly lower than that of the Greek general population, standardized mortality ratio (SMR) was 0.71 (95% CI 0.53–0.93). Mortality due to cancer was increased (SMR 1.15, 95% CI 0.77–1.67), mainly due to lung cancer mortality (SMR 1.71, 95% CI 0.98–2.78), but not significantly. Conclusions: Occupational exposure to relatively pure chrysotile within permissible levels was not associated with a significant increase in lung cancer or with mesothelioma. Decreased overall mortality of workers indicates a healthy worker effect, which – together with the relatively small cohort size – could have prevented small risks to be detected.

Mortality in a cohort of cement workers in a plant of Central Italy

“…In Greece, Sichletidis et al (2009) considering a cohort of workers exposed to chrysotile found that the mortality for "all causes" was lower than that of the general population. Forastiere et al (1989) compared the mortality of a cohort of workers compensated for silicosis, and deceased in the period 1969-1984, with Latium population as in the present paper.…”

Lung Diseases - Selected State of the Art Reviews

“…The amphibole and amosite are reported to carry the greater risk of causing other asbestos-related diseases such as pleural plaque, mesothelioma and lung cancer. Exposed workers who have developed asbestosis are at risk of fatal complications (Wagner, 1997;Sichletidis et al, 2009;Mossman et al, 1990). In patients with asbestosis, the chest radiograph usually shows small bilateral parenchymal opacities with a multinodular or reticular pattern that may be associated with pleural abnormalities.…”

“…Torbica and Krstev (2006) suggested that asbestos-related diseases in dentists might be linked to exposure to inorganic dust in the manufacturing of cobalt-chromiummolybdenum-based dental protheses. With the use of white asbestos-made lining material for casting rings in dentistry, dental technicians and dentists are potentially exposed to asbestos; and some cases of pleural plaques and malignant mesothelioma have been reported in a number of dentists after a relatively long period of work (35 to 45 years) (Choel et al, 2001;Reid et al, 1991;Sichletidis et at, 2009;Radi et al, 2002). Similarly, pneumoconiosis may occur in mechanics.…”

Chrysotile as optimal reinforcing agent for fiber-reinforced concrete

“…Достоверно известно, что высокие уровни экспозиции приводят к возникновению заболеваний раком лег-ких, но снова в исследованиях часто нет дифференциации по влиянию различных видов асбеста. Вопрос относительно того, вызывают ли низкие экспозиции риск развития рака легких, поскольку они ниже ку-мулятивного воздействия, находится в стадии изучения [10,13,[17][18][19][20][21][22][23][24][25][26][27][28].…”

“…Во многих исследованиях [10,11,[17][18][19][20][21][22][23][24][25][26][27][28][29][30]] было показано, что хри-зотил не обладает теми же активными биологическими свойствами и онкоопасностью, что и амфиболы, и выводится из легких быстрее, чем амфиболовые волокна. В настоящее время получает распространение большое количество аналогов хризотил-асбеста, различных по своим химическим и физико-механическим свойствам: стеклянные, базальтовые, керамические, по-лимерные и др.…”