25 May, 2018

Air pollution scare debunked

Greenies love to condemn urban air pollution and say how bad for us it is. Faulty science on fine particulate pollution (PM2.5) was the bedrock of the Obama EPA’s war on coal. Particulates don’t just make you sick; they are directly related “to dying sooner than you should,” EPA Administrator Lisa Jackson falsely told Congress. There is no level “at which premature mortality effects do not occur,” Mr. Obama’s next Administrator Gina McCarthy dishonestly testified. See also some of my previous comments here

The latest research findings below are very powerful evidence on the question. The study included the entire Medicare population from January 1, 2000, to December 31, 2012. And their finding that only one in a million people die from particulate air pollution is pretty decisive. If you bother about that tiny risk, you should never get out of bed.

The authors pretend that their findings support the Greenies but they would have been reviled if they had said the truth:  That their findings show that air pollution is not dangerous.

Air pollution from smoky cooking-fires has probably been part of the human experience for something like a million years and we have adapted to it.  We just cough it up.

Association of Short-term Exposure to Air Pollution With Mortality in Older Adults

Key Points

Question:  What is the association between short-term exposure to air pollution below current air quality standards and all-cause mortality?

Finding:  In a case-crossover study of more than 22 million deaths, each 10-?g/m3 daily increase in fine particulate matter and 10–parts-per-billion daily increase in warm-season ozone exposures were associated with a statistically significant increase of 1.42 and 0.66 deaths per 1 million persons at risk per day, respectively.

Meaning:  Day-to-day changes in fine particulate matter and ozone exposures were significantly associated with higher risk of all-cause mortality at levels below current air quality standards, suggesting that those standards may need to be reevaluated.

Abstract

Importance:  The US Environmental Protection Agency is required to reexamine its National Ambient Air Quality Standards (NAAQS) every 5 years, but evidence of mortality risk is lacking at air pollution levels below the current daily NAAQS in unmonitored areas and for sensitive subgroups.

Objective:  To estimate the association between short-term exposures to ambient fine particulate matter (PM2.5) and ozone, and at levels below the current daily NAAQS, and mortality in the continental United States.

Design, Setting, and Participants:  Case-crossover design and conditional logistic regression to estimate the association between short-term exposures to PM2.5 and ozone (mean of daily exposure on the same day of death and 1 day prior) and mortality in 2-pollutant models. The study included the entire Medicare population from January 1, 2000, to December 31, 2012, residing in 39 182 zip codes.

Exposures:  Daily PM2.5 and ozone levels in a 1-km × 1-km grid were estimated using published and validated air pollution prediction models based on land use, chemical transport modeling, and satellite remote sensing data. From these gridded exposures, daily exposures were calculated for every zip code in the United States. Warm-season ozone was defined as ozone levels for the months April to September of each year.

Main Outcomes and Measures:  All-cause mortality in the entire Medicare population from 2000 to 2012.

Results:  During the study period, there were 22 433 862 million case days and 76 143 209 control days. Of all case and control days, 93.6% had PM2.5 levels below 25 ?g/m3, during which 95.2% of deaths occurred (21 353 817 of 22 433 862), and 91.1% of days had ozone levels below 60 parts per billion, during which 93.4% of deaths occurred (20 955 387 of 22 433 862). The baseline daily mortality rates were 137.33 and 129.44 (per 1 million persons at risk per day) for the entire year and for the warm season, respectively. Each short-term increase of 10 ?g/m3 in PM2.5 (adjusted by ozone) and 10 parts per billion (10−9) in warm-season ozone (adjusted by PM2.5) were statistically significantly associated with a relative increase of 1.05% (95% CI, 0.95%-1.15%) and 0.51% (95% CI, 0.41%-0.61%) in daily mortality rate, respectively. Absolute risk differences in daily mortality rate were 1.42 (95% CI, 1.29-1.56) and 0.66 (95% CI, 0.53-0.78) per 1 million persons at risk per day. There was no evidence of a threshold in the exposure-response relationship.

Conclusions and Relevance:  In the US Medicare population from 2000 to 2012, short-term exposures to PM2.5 and warm-season ozone were significantly associated with increased risk of mortality. This risk occurred at levels below current national air quality standards, suggesting that these standards may need to be reevaluated.

SOURCE





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