Study alleges drywall-based asbestos exposure is safe, but drywall workers suggest otherwiseIn the world of medical studies, it is important to pay attention to the details: an investigation's limits, its author's declarations of interest, a study's funding and so on. These specifications often clue you, the reader, into an underlying financial or legal interest that ay not be immediately apparent. A case in point is a newly published study alleging that exposure to asbestos-laden drywall does not lead to mesothelioma or other respiratory illnesses.
At first, the report seems quite thorough. But take a closer look, and you'll notice that a few things are amiss.
The thesis: Chrysotile fibers are shorter and less "potent" than other kinds
The study appeared in the January 2012 issue of the journal Critical Reviews in Toxicology. Its authors work for a consulting firm. If you look into the firm's most recent cases, it has petitioned the Environmental Protection Agency and the Occupational Safety and Health Administration, respectively, to declare safe (a) the rubber mulch used for ground cover in children's playgrounds and (b) diacetyl and 2,3-pentanedione, two butter-flavored chemicals known to cause lung disease in popcorn factory workers.
This should immediately raise a bit of readerly suspicion.
In the study itself, researchers reasoned that chrysotile asbestos is less potent than other kinds, and that exposure to chrysotile-laden drywall does not lead to respiratory diseases. They marshaled quite a few studies suggesting that asbestos-based drywall contains very short (< five nanometers) chrysotile asbestos fibers, that inhaled asbestos drywall compounds probably don't stay in the lungs and that drywall workers don't have an increased risk of death from pulmonary disease.
The missing facts: Even minimal asbestos exposure can be dangerous
Here are some things you won't read in the study.
- It is true that asbestos fibers shorter than five nanometers are less likely to cause acute pleural inflammation, as reported in a new study in the journal Toxicological Sciences. But that does not indicate that such fibers can be safely inhaled in any great quantity.
- Chrysotile asbestos fibers cannot be considered safer than other forms of asbestos. Former Assistant Surgeon General Richard Lemen has stated unequivocally that "[in] 30 years, science has not changed its opinion that all forms of asbestos, including chrysotile, cause mesothelioma."
- A pair of studies from 1979 and 1980, both published in the American Industrial Hygiene Association Journal, stated that that drywall tapers were often exposed to asbestos levels several times higher than the maximum safe amount dictated by federal health authorities.
- Recently, a San Francisco jury awarded nearly $6 million to the family of a deceased asbestos-drywall hanger who developed mesothelioma after years of exposure to toxic fibers.
Finally, it is important to look at the study's declaration of interest. It states that the report was partially funded by two asbestos-drywall manufacturers, both of whom are currently embroiled in litigation concerning "possible exposure to asbestos by individuals handling drywall accessory products as career tradesmen or during home renovation projects."
Interestingly, the San Francisco drywall hanger who died of mesothelioma was employed by one of these very companies!
Rare polyps may develop as a consequence of malignant mesothelioma, http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3481150/, 11/6/12
Asbestos exposure led to death of Merchant Navy man, http://www.getbracknell.co.uk/news/s/2123312_former_merchant_navy_man_died_from_mesothelioma_after_inhaling_asbestos_fibres, 11/5/12
Siblings honor father-son mesothelioma victims, http://www.hartlepoolmail.co.uk/community/taking-to-skies-for-dad-and-brother-1-5064192, 10/31/12
Former students, colleagues rally around coach who has mesothelioma, http://hinsdale.suntimes.com/sports/15657700-419/badminton-legend-battling-cancer.html, 10/23/12
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Mesothelioma fundraiser celebrates third year, http://www.wowktv.com/story/19600262/putnam-woman-organizes-fundraiser-in-memory-of-father, 9/24/12
Charity 5k walk/run to raise money for mesothelioma research, http://www.theday.com/article/20120918/NWS01/120919658/1019&town=, 9/21/12
Family of five sisters to raise funds for mesothelioma charity, http://www.thisissomerset.co.uk/Sisters-plan-family-fun-day-memory-father/story-16840190-detail/story.html, 9/20/12