Can PM 2.5 lead to early mortality?

The question on the table is: Is there a cause-and-effect relationship between fine particulate matter pollution (PM 2.5) and premature death?

Here is what one newspaper columnist had to say.

“I’ve done numerous stories on studies showing that PM2.5 isn’t killing Californians,” Lois Henry insisted in her “Enforcing smog rules this way is bad for business” commentary in the Oct. 23, 2013 Bakersfield Californian. “And, in fact, a growing number of studies are showing PM2.5 has zero effect on premature deaths.”1

Are others saying otherwise and, if so, who?

While I personally cannot refute Henry’s assertions, what I can do is provide relevant testimony of different sources related to the topic at hand. Several examples are provided below.

“PM2.5 has been associated with an increased risk of premature mortality, increased hospital admissions for heart and lung disease, and increased respiratory symptoms. Long-term exposure to components of diesel exhaust, including diesel PM and diesel exhaust organic gases, are likely to pose a lung cancer hazard,” declared the U.S. Environmental Protection Agency (EPA) in “Second Report to Congress: Highlights of the Diesel Emissions Reduction Program.”2

“Fine particle pollution can penetrate deep into the lungs and has been linked to a wide range of serious health effects, including premature death, heart attacks, and strokes, as well as acute bronchitis and aggravated asthma among children,” the EPA reported in its Dec. 14, 2012 news release: “EPA Announces Next Round of Clean Air Standards to Reduce Harmful Soot Pollution.”

PM 2.5 is particulate matter pollution 2.5 micrometers or less in diameter. (See: “EPA, Valley Air District PM 2.5 standards separate and unequal”).

Furthermore, in a portable document format document from the California Environmental Protection Agency Air Resources Board (ARB) titled: “Facts About Particulate Matter Mortality: New data revealing greater dangers from PM2.5,” the ARB is quite resolute: Stressed is that premature deaths linked with outdoor fine particulate matter levels is backed up by a sizable body of evidence. Work done similar to that of ARB’s in this regard by the World Health Organization and U.S. EPA and given a stamp of approval by the likes of the Health Effects Institute and other medical associations, provides confirmation, the ARB in the document in question brought to bear.

Meanwhile, in “Examination of engine idling in editorial goes the extra mile,” in citing Monica Maye, author of “Idling vehicles raise risks, get you nowhere,” I wrote: “Maye also opines there is a tendency in diesel truck and bus operation for increased idling time with consequent negative ‘local’ air-quality impacts, and adds, ‘Diesel exhaust contains both carbon particulates and 40 chemicals that are classified as ‘hazardous air pollutants’ under the Clean Air Act.’”

Then there is this item: the Air Quality Index (AQI). Regarding the AQI, where I live there are six relevant categories or ranges that apply. These are:

0-50 – Good (green)

51-100 – Moderate (yellow)

101-150 – Unhealthy for Sensitive Groups (orange)

151-200 – Unhealthy (red)

201-300 – Very Unhealthy (violet)

301-500 – Hazardous (dark purple)

Basically between April and November, applicable to the scale is ozone and the applicable pollutant between November and April? Particulate matter. The official season for ozone, incidentally, starts in March and goes all the way through October.

At any rate, if PM 2.5 is not unhealthy, then why a corresponding scale related to such and at times fine particulate matter readings go above 100, why the associated “Unhealthy” or “Hazardous” designations?

Think about it.


  1. Lois Henry, “Enforcing smog rules this way is bad for business,” Bakersfield Californian, Oct. 23, 2013. Henry’s op-ed is the last article of the grouping.
  2. “Second Report to Congress: Highlights of the Diesel Emissions Reduction Program,” Energy Policy Act of 2005, Title VII, Subtitle G, Sections 791-797, United States Environmental Protection Agency, “Prepared by: U.S. EPA’s Office of Transportation and Air Quality,” Washington, D.C., p. 9.

– Alan Kandel

This post was last revised on Jan. 29, 2020 @ 6:25 a.m. Pacific Standard Time.

2 thoughts on “Can PM 2.5 lead to early mortality?”

  1. Readers may be interested in reading the following documents:

    “Mortality in the Medicare Population and Chronic Exposure to Fine Particulate Air Pollution in Urban Centers (2000-2005)” by Scott L. Zeger, Francesca Dominici, Aidan McDermott and Jonathan M. Samet, Environmental Health Perspectives, U.S. National Library of Medicine, National Institutes of Health.

    “Special Report: Tobacco Industry Efforts Undermining Evidence Linking Secondhand Smoke With Cardiovascular Disease” by Elisa K. Tong, MD, MA; Stanton A. Glantz, PhD, the American Heart Association.

    “Short-term Exposure to Particulate Matter Constituents and Mortality in a National Study of U.S. Urban Communities” by Jenna P. Krall, G. Brooke Anderson, Francesca Dominici, Michelle L. Bell and Roger D. Peng, Environmental Health Perspectives, National Institutes of Health, National Institute of Environmental Health Sciences.

    “HEI’s National Particle Component Toxicity (NPACT) Initiative, HEI NPACT Review Panel, Executive Summary,” Health Effects Institute, Oct. 2013.

Comments are closed.