A new study led by researchers from the National Cancer Institute provides further evidence of the cancer risk associated with exposure to all types of asbestos. Since the 1950s, researchers have warned that asbestos exposure is the leading cause of mesothelioma, a cancer occurring in the thin layer of tissue that covers most of the body’s internal organs, but some have questioned whether all types of asbestos are equally toxic for humans. In this new study, published in the journal Occupational & Environmental Medicine on October 21, researchers investigated whether the risk of mesothelioma differs among people exposed to only chrysotile asbestos compared with chrysotile and ≥1 amphibole (ie, amosite, tremolite, anthophyllite and crocidolite), and found that asbestos raises the risk of mesothelioma, regardless of type.
Asbestos is a mineral that occurs naturally in certain types of rock and is mined from the earth’s surface. All forms of asbestos are resistant to heat, chemical, fire and biological breakdown, which means the fibers do not burn, break down significantly in the environment or undergo significant reactions with chemicals. These properties made asbestos commercially desirable and the mineral was widely used as a building material, in roofing shingles, ceiling and floor tiles and house siding. It was also used in heat-resistant fabrics, brake linings, pads and shoes, packing materials and asphalt road surfacing, in addition to other industry, construction and commercial uses. In fact, thousands of domestic, industrial and commercial products were once manufactured using asbestos fibers, and while most U.S. companies stopped using asbestos decades ago, the mineral can still be found in many older homes and buildings across the country. Asbestos is no longer mined in the U.S. and its use is highly regulated here. However, while more than 50 countries have gone so far as to ban the use of asbestos, the United States is not one of them.
Most asbestos exposure is occupational, meaning it occurs in the workplace among those who work with asbestos or asbestos-containing materials, such as building materials, automotive parts, fireproofing, insulation or certain plastics, paints and adhesives, although environmental and secondary exposure is also a risk. Potentially harmful exposure to asbestos occurs when microscopic asbestos fibers become airborne and are inhaled or ingested. When asbestos dust is disturbed, it can remain in the air for hours, putting anyone nearby at risk for toxic exposure. Over time, asbestos dust or fibers trapped in the lungs can cause inflammation and scarring, called asbestosis, and prolonged exposure to asbestos can lead to serious health consequences, such as lung cancer or mesothelioma. In fact, mesothelioma is almost exclusively caused by exposure to asbestos and the mineral has also been linked to an increased risk of ovarian cancer, laryngeal cancer and other types of cancer.
There are six types of asbestos that fall into two main categories: serpentine and amphiobole. Serpentine asbestos fibers are long, flexible and curved and the fibers can be woven together. The most common type of serpentine asbestos is chrysotile (white asbestos), which is the type most commonly used in manufacturing. Amphiobole asbestos, on the other hand, is less useful for commercial purposes because the fibers are straight, stiff and brittle. Amphiobole asbestos has five sub-types, including crocidolite (blue asbestos), amosite (brown asbestos), actinolite, anthophyllite and tremolite. Scientists have known for decades that asbestos is a carcinogen, meaning it causes cancer in humans, but the researchers in this new study sought to determine whether the risk of mesothelioma differs among workers exposed to only chrysotile asbestos and workers exposed to chrysotile-amphibole mixtures.
In order to compare the toxic effects of exposure to chrysotile asbestos versus chrysotile-amphibole mixtures, the researchers examined occupational data on 580 workers from a case-control study of mesothelioma conducted in the United States from 1975-1980. Asbestos exposure among the workers included exposure to chrysotile asbestos and nine chrysotile–amphibole mixtures, and the researchers found that while exposure to chrysotile only was associated with an increased risk of mesothelioma compared to no exposure, “the complex mixture of extra-long amosite, short and long chrysotile, tremolite and anthophyllite was associated with the highest [mesothelioma] risk.” Based on their findings, the researchers concluded that “policies aimed at regulating asbestos should target both pure chrysotile and mixtures that include amphibole.”
Despite extensive scientific research linking asbestos exposure to mesothelioma and other severe health consequences, the United States continues to import and use asbestos, and there are hundreds of consumer products that can still legally contain small amounts of the carcinogenic mineral. Just last year, amid thousands of claims that Johnson & Johnson’s talc-based baby powder can cause mesothelioma and ovarian cancer, the company recalled the baby powder after the FDA found traces of chrysotile asbestos in a bottle purchased from an online retailer. If you or someone you love was exposed to asbestos and developed mesothelioma, ovarian cancer or another serious side effect, contact us today to find out how we can help. You may have grounds to file a personal injury or wrongful death lawsuit against the at-fault company, seeking compensation to cover the cost of medical bills, lost income, funeral expenses and other damages.