For years, I warned my students, and almost anyone who would listen to me, to immediately deploy red flags when phrases like “studies show” and “research suggests” begin sentences in argumentation. Often the assertions that follow aren’t supported by the study implied.
I recently read Beth Adams’ opinion piece warning others about people like me, “pellet promoters.” I read several paragraphs of generalization before encountering this sentence: “A June 2015 study by Yuanli Shi and others found that low levels of PM2.5 (particulates less than 2.5 micrometers in size) were associated with increased mortality.”
While this sentence is also quite vague, the thesis was interesting. I was able to find only one study published in 2015 with Yuanli Shi listed among the authors, so I read “Ischemic Heart Disease Mortality and Long-Term Exposure to Source-Related Components of U.S. Fine Particle Air Pollution” by George D. Thurston, Richard T. Burnett, Michelle C. Turner, Yuanli Shi, Daniel Krewski, Ramona Lall, Kazuhiko Ito, Michael Jerrett, Susan M. Gapstur, W. Ryan Diver and C. Arden Pope III.
The research report was published in an NIH journal in 2015 and is available at ehp.niehs.nih.gov/wp-content/uploads/advpub/2015/12/ehp.1509777.acco.pdf
I’m surprised this research was cited for three reasons.
First, it is a study based on a large number of participants from 100 metropolitan regions of the U.S. where elemental carbon particulates from fossil fuel combustion abound.
Second, the study repeatedly exempts small particles from soil and biomass combustion from impact on mortality rates due to ischemic heart disease (IHD).
And third, the study’s elegant design differentiates among particulate sources when discussing health impacts, thereby disallowing future gross generalization about fine particles and health.
We do need to understand the impact of all atmospheric inclusions on public health, and we need to be very precise when discussing those inclusions and impacts.
On pages 11, 13, and 18 of the study report, crustal soil particulates and particulates arising from biomass combustion were expressly eliminated from the list of those creating increased rates of death due to ischemic heart disease.
I must admit that the broad-brush nature of the argument and this incongruous reference to a study contradicting the thesis of the piece didn’t provoke me to further review it carefully.
The following quote from page 31 in the study report, the discussion section, did reflect an observation made by Richard Peltier during his presentation in Greenfield.
“Although this is a US-based study of older adults, these findings have potentially broad policy implications: as the developing world deals with an increasing disease burden from air pollution, reductions in fossil fuel combustion, and especially coal-combustion, may well be the most efficacious policy approach to reduce air pollution’s global human health burden. ”
Dr. Peltier noted that significant portions of both the fossil fuel and biomass fractions of the particulate mass in the air have unknown chemical composition. He opined that he, personally, was more worried about the health impact of particulates in the unresolved fossil fuel fractions than those in the unresolved biomass fractions.
I will continue to promote wood pellet central heating as a responsible use of a regionally-produced, renewable fuel replacement for fossil fuels and will continue to be interested in ways to ensure that all forms of combustion-based heating are ever cleaner.
Harry “Dutch” Dresser is the managing director of Maine Energy Systems in Bethel, Maine.