Researchers at Cardno ChemRisk, a California-based scientific consulting firm, analyzed data collected by the Occupational Safety and Health Administration (OSHA) between 1984 and 2011. OSHA conducts inspections to measure asbestos concentrations because of the link between asbestos exposure and lung diseases like malignant mesothelioma.
The bad news is that many of the air samples collected contained dangerously high levels of asbestos fibers, well beyond what OSHA allowed. This was the case even decades after asbestos was identified as the primary cause of mesothelioma.
“Asbestos compliance sampling data associated with the construction, automotive repair, manufacturing, and chemical/petroleum/rubber industries included measurements in excess of 10 f/cc, and were above the permissible exposure limit from 2001 to 2011,” reports supervising health scientist Dallas Cowan, PhD, in Regulatory Toxicology and Pharmacology.
Dr. Cowan notes that the study was limited by problems like sampling bias and errors in user-entered data. Even so, the researchers did uncover some good news in the data – especially for people who are most likely to be at higher risk for mesothelioma because they worked in one of the studied industries.
The positive message from the new study is that the trend in airborne concentrations of asbestos in workplaces has steadily declined over the past three decades. The study’s authors say the decline mirrors the decreasing use of asbestos in the US and the declining mesothelioma incidence rates. Their report includes recommendations for ways that OSHA could improve its asbestos databases.
Beginning in the 1930s and continuing for more than 40 years, asbestos, a naturally strong and heat-resistant mineral fiber, was heavily used in industries ranging from construction to manufacturing to shipbuilding. After asbestos was linked to mesothelioma, the government placed heavy restrictions on its use and handling. Many other countries have since banned the material.
While compliance with OSHA regulations has reduced the number of workers who get mesothelioma, many people are still living with the threat of the disease because of its long latency period. It is possible to develop mesothelioma even decades after being exposed to asbestos.
Cowan, DM, et al, “Analysis of Workplace Compliance Measurements of Asbestos by the US Occupational Safety and Health Administration”, May 15, 2015, Regulatory Toxicology and Pharmacology, Epub ahead of print