Italian researchers say cases of lung cancer among people who work with asbestos-based clutches and brakes in the country have probably been underestimated. And it remains to be seen how many of these workers end up contracting malignant mesothelioma.
The study was led by occupational medicine experts from the province of Brescia. They focused on an Italian company that produced asbestos-based clutches and brakes for more than 20 years.
The team conducted an analysis of the workers’ likely asbestos exposure levels. These levels were compared to the incidence of asbestos-related diseases like lung cancer, asbestosis, and pleural mesothelioma.
The conclusion? The risk is bigger than anyone realized.
Mesothelioma Risk from Asbestos-Based Clutches and Brakes
Asbestos is a fibrous mineral that has to be mined from the earth. It is strong, plentiful, inexpensive, and flexible. It is also virtually impervious to heat. These qualities made asbestos popular with manufacturers beginning in the early 1900s.
Car makers realized that asbestos-based clutches and brakes would last longer than other materials. Friction in these car parts generates a lot of heat. But asbestos could handle it.
Unfortunately, asbestos dust causes malignant mesothelioma and other serious diseases. The fibers stay in the lungs or tissue. They can cause cancerous changes at the cellular level over time. Exposed people may get sick with mesothelioma or lung cancer many years later. By the time companies understood the risk, many workers had already been exposed.
The Italian plant in the new study produced asbestos-based clutches and brakes from 1971 to 1993. Hundreds of workers suffered asbestos exposure during that time. The researchers wanted to see how many of them received a diagnosis of mesothelioma or another asbestos-disease.
Lung Cancer, Mesothelioma, and Asbestosis Among Plant Workers
Any amount of asbestos exposure can lead to malignant mesothelioma. But people who are exposed to higher levels or for longer periods of time have the highest risk.
The US Occupational Safety and Health Administration says workers should never be exposed to more than 0.1 fibers per cubic centimeter for more than 30 minutes.
In 1982, Italian health authorities tested the air at the plant that produced asbestos-based clutches and brakes. The concentration of asbestos fibers was 0.3 fibers per cubic centimeter. That measurement went down to less than 0.1 f/cc in 1992. But the damage was already done for many workers.
Four of them developed pleural plaques. Three received a diagnosis of asbestosis and seven got lung cancer. There were no cases of malignant mesothelioma. But the researchers say that is probably because it has not been long enough.
“A subset of the blue collar employees, the ones employed later on, could still have not reached the full risk condition, and so being still at risk of developing malignant mesothelioma,” writes study author Pietro Gino Barbieri.
Barbieri says the asbestos-based clutches and brakes probably caused even more cases of lung cancer. The researchers say health officials should go back and look closer at deaths among plant workers.
“Lung cancer occurrence in the population of blue collar employees has been likely underestimated and the correct determination of lung cancer risk should be done through the mortality analysis of this population,” the study concludes.
Barbieri, PG, et al, “[Asbestos exposure and related diseases among friction products workers (1971-2016)]”, Italian Journal of Occupational Medicine and Ergonomics, September 2020, pp. 145-152, https://europepmc.org/article/med/33119974
Asbestos: OSHA Fact Sheet, https://www.osha.gov/Publications/OSHA3507.pdf
Pawelczyk, A and Bozek, F, “Health risk associated with airborne asbestos”, June 13, 2013, Environmental Monitoring and Assessment, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4464730/