every breath you take

August 14, 2018 8:09 AM

The Weight of Numbers: Air Pollution and PM2.5

Emanating from smokestacks, vehicle engines, construction projects, and fires large and small, airborne pollution – sometimes smaller than the width of a human hair, and very often the product of human activity – is not just contributing to climate change. It is a leading driver of heart disease and stroke, lung cancer, and respiratory infections the world over. Exposure to such pollution, the most deadly of which scientists call PM2.5, is the sixth highest risk factor for death around the world, claiming more than 4 million lives annually, according to recent global morbidity data. Add in household pollutants from indoor cooking fires and other combustion sources, and the tally approaches 7 million lives lost each year.

Gasping for Air in India’s Industrial North - "Air pollution kills one million Indians annually. In the northern city of Patna, the problem shaves four years, on average, off residents’ lives."

"Particle pollution, also called particulate matter or PM, is a mixture of solids and liquid droplets floating in the air. Some particles are released directly from a specific source, while others form in complicated chemical reactions in the atmosphere."
PM10: "PM10 is particulate matter 10 micrometers or less in diameter, "
PM2.5: "fine particulate matter" "with a size (diameter) generally less than 2.5 micrometres (µm)" generally "emitted during the combustion of solid and liquid fuels, such as for power generation, domestic heating and in vehicle engines."
Ozone (O3): "Ground level or "bad" ozone is not emitted directly into the air, but is created by chemical reactions between oxides of nitrogen (NOx) and volatile organic compounds (VOC) in the presence of sunlight."
Nitrogen dioxide (NO2): "primarily gets in the air from the burning of fuel. NO2 forms from emissions from cars, trucks and buses, power plants, and off-road equipment."

State of Global Air Report 2018 [PDF] -

The State of the Air 2018 - "The "State of the Air 2018" found ozone pollution worsened significantly in 2014-2016 compared to the previous report, while improvements continued in year-round particle pollution and fewer episodes of high particle days. This year's report provides continued evidence that the United States must continue to fight climate change and support and enforce the Clean Air Act to protect the nation from unhealthy air."


AirVisual: Earth, an interactive rotatable realtime air quality and wind pattern globe.

Why Do Heat Waves Make Ozone Pollution So Much Worse?
Technology can be improved in developed countries, and spread much more widely in developing countries

Even low levels of air pollution linked with serious changes in the heart, according to new UK research
Particulate Matter Exposure and Stress Hormone Levels
Asthma and PM10
The impact of PM2.5 on the human respiratory system
An ecological analysis of PM2.5 concentrations and lung cancer mortality rates in China
Ozone pollution in US national parks close to that of largest US cities
China has a new air-pollution crisis in ozone
Changes in Transportation-Related Air Pollution Exposures by Race-Ethnicity and Socioeconomic Status: Outdoor Nitrogen Dioxide in the United States in 2000 and 2010

posted by the man of twists and turns (13 comments total)

Working my way through these links (rather than working, in the fine MetaFilter tradition) - these are excellent.

Air Quality Index here in Seattle 142 including a heaping serving of PM2.5.

AirVisual: Earth is mesmerizing. Makes me wonder what the story is behind each patch of pollution.
posted by skyscraper at 8:45 AM on August 14, 2018

Here's a good site for looking up real-time air quality measurements internationally. It's not too bad a day in Hamilton, but PM2.5 levels are rising...
http://aqicn.org/city/all/

[edit] holy crap Oregon - shut your windows :(
posted by Popular Ethics at 9:04 AM on August 14, 2018 [2 favorites]

Thanks for compiling this post, with links to good explanations of what kinds of air pollution cause what problems. In spite of highway signs advising of ozone alert days, I haven't found many people who know what that means and what they should do about it. First and easiest step: don't pump gas while it's hot.

It's often easier to get people interested in the idea of reducing the amount of local automobile travel by focusing on local harms to vulnerable populations than with even mentioning global climate change. "Your carpool could keep your asthmatic kid or their classmate out of the ER" is more motivating than "your carpool could give your kid a chance at a better future".
posted by asperity at 9:19 AM on August 14, 2018 [7 favorites]

What's the middle of Pennsylvania? the southern tier of New York? that has PM2.5 values in the 160s?
posted by kokaku at 9:43 AM on August 14, 2018

capitalism's free externalities : Immiserating, sickening and shortening the life of more people than any other issue facing humanity.
posted by lalochezia at 10:38 AM on August 14, 2018 [5 favorites]

Here is another visualization of air quality, but it can also be set to many different things [different PM sizes, SO4, CO2, and other things like waves and currents]. I often use it to monitor various natural disasters, and to illustrate real world connections in science courses.
posted by Acari at 1:09 PM on August 14, 2018 [6 favorites]

Thanks for putting this together. I keep bringing air pollution up when people foment about terrorism in London, where air pollution is killing, on average, a person every hour.
posted by lucidium at 1:57 PM on August 14, 2018 [1 favorite]

[edit] holy crap Oregon - shut your windows :(
Yeah, it's bad (again). Last year, here in Portland, the sky was red for weeks during the wild fires in the gorge just east of the city. This year, we are getting the smoke from all the surrounding wild fires (some as far away as Vancouver, BC and California, supposedly).

The sky has a particularly depressing yellow-brown coloration. The sunlight is tinted sepia. Last night the moon was pink. Tonight will likely be not much better.

The "good news"? We probably won't reach the forecast 100°F today. We'll only hit about 97° because of the ash in the air blocking some of the sunlight.

Oh, and ash. The air smells like burnt. Not like a campfire, or anything really identifiable. Just burnt. Everyone is reporting shortness of breath and/or their lungs hurting. Congestion and sinus irritation being the most minor symptoms. There is a fine layer of ash accumulating on most surfaces. You can definitely see if on most parked cars. The air is unusually dry.
posted by daq at 2:20 PM on August 14, 2018 [1 favorite]

FYI, AQICN does not properly poll Oregon’s servers for data from the state’s air quality monitoring. Use their website or their mobile app (search Oregon air) if you want to see the data right from the source. It is quite bad right now, ironically during the National Ambient Air Monitoring Conference, coincidentally being held in Portland this week.
posted by Strudel at 11:05 PM on August 14, 2018 [1 favorite]

There are low-cost sensors for monitoring PM2.5 levels in your home or backyard (with varying degrees of accuracy). When it becomes a health risk, HEPA-filtered fans can be used to remove the particulates from indoor air. I've taken to running one in the baby's room whenever the neighborhood PurpleAir sensor flags a bad air day.
posted by ContinuousWave at 12:38 AM on August 15, 2018 [1 favorite]

Thanks for putting together such a comprehensive post.
posted by theora55 at 7:58 AM on August 15, 2018

What's the middle of Pennsylvania? the southern tier of New York? that has PM2.5 values in the 160s?

Where are you seeing PM2.5 values that high? AirVisual seems to show most of western NY and PA in the 40s at the highest.

There are some big coal-fired power plants out there, though, and western PA still has a significant amount of primary steel production.
posted by Kadin2048 at 9:10 AM on August 15, 2018

How Air Pollution Causes Diabetes

Scientists are just beginning to understand what exactly makes PM2.5 so harmful, but a major reason is that it’s so small and contains toxic metals. Its size allows it to penetrate the lungs and enter the bloodstream. There, it can circulate to different organs and cause inflammation. The inflammation increases insulin resistance. Eventually, this insulin resistance can become so severe the pancreas becomes unable to pump out enough insulin to compensate, and diabetes can set in.

Previous research has found that Latino children living in areas with more air pollution had a greater risk of developing type 2 diabetes. But other studies on the association between the two have generated mixed results.

This new study makes an even stronger case, suggesting that the current limits on air pollution in the United States might be too high. The EPA’s pollution threshold on particulate matter is 12 μg/m3, or micrograms per cubic meter of air, but this study says the risk of diabetes starts at about 2.4 μg/m3. Among people exposed to between five and 10 μg/m3 of particulate matter, about 21 percent developed diabetes. At the threshold of current “safe” levels, 24 percent do. For each 10 μg/m3 increase in particulate matter, the risk of developing diabetes goes up by 15 percent. This risk is present regardless of whether the individual becomes obese or not.

But this study and others might not lead to a tightening of the PM2.5 standards because, under a rule proposed by the Trump administration in April, all studies used by the EPA to make air and water regulations must make their underlying data publicly available. As my colleague Robinson Meyer reported, studies like this and others, which show the detrimental health impacts of pollution, are based on health data that is confidential and cannot be de-anonymized.

The 2016 global and national burden of diabetes mellitus attributable to PM2·5 air pollution, Benjamin Bowe, MPH, Yan Xie, MPH, Tingting Li, MD, Prof Yan Yan, MD, Prof Hong Xian, PhD, Ziyad Al-Aly, MD. The Lancet Planetary Health. VOLUME 2, ISSUE 7, PE301-E312, JULY 01, 2018

Findings: We examined the relationship of PM2·5 and the risk of incident diabetes in a longitudinal cohort of 1 729 108 participants followed up for a median of 8·5 years (IQR 8·1–8·8). In adjusted models, a 10 μg/m3 increase in PM2·5 was associated with increased risk of diabetes (HR 1·15, 95% CI 1·08–1·22). PM2·5 was associated with increased risk of death as the positive outcome control (HR 1·08, 95% CI 1·03–1·13), but not with lower limb fracture as the negative outcome control (1·00, 0·91–1·09). An IQR increase (0·045 μg/m3) in ambient air sodium concentration as the negative exposure control exhibited no significant association with the risk of diabetes (HR 1·00, 95% CI 0·99–1·00). An integrated exposure response function showed that the risk of diabetes increased substantially above 2·4 μg/m3, and then exhibited a more moderate increase at concentrations above 10 μg/m3. Globally, ambient PM2·5 contributed to about 3·2 million (95% uncertainty interval [UI] 2·2–3·8) incident cases of diabetes, about 8·2 million (95% UI 5·8–11·0) DALYs caused by diabetes, and 206 105 (95% UI 153 408–259 119) deaths from diabetes attributable to PM2·5 exposure. The burden varied substantially among geographies and was more heavily skewed towards low-income and lower-to-middle-income countries.
Interpretation:
The global toll of diabetes attributable to PM2·5 air pollution is significant. Reduction in exposure will yield substantial health benefits.

posted by the man of twists and turns at 3:34 PM on August 15, 2018 [1 favorite]