Tuesday, July 4, 2017

Increased Air Pollution Cuts Lifespan by a Decade #Science #Health #Environment

Credit: CC0 Public Domain

Phys.org:  Increased air pollution cuts victims' lifespan by a decade, costing billions

Hold on before you go berserk over a scare headline.

There are generally two types of science.  There is that which is based on empirical data so someone saw it, whatever it was.  There's also science which extrapolates from available data to present some conclusion in the future.

Generally we're accepting of science from empirical data but not so much any extrapolated science.  For any type of environmental science beyond a daily weather report, many just don't believe it.

However, we're skeptical as well but we proceed.

One of the benefits to cutting fossil fuel consumption is lowering air pollution. A new study in the August issue of Ecological Indicators shows that, on average, an increase in pollution particles in the air of 10 micrograms per cubic meter cuts victims' life expectancy by 9-11 years - more than previously thought. But the estimated economic cost of this differs wildly between the US and the EU because of the calculations used.

- PO

It's empirical so far since they observed the situation and made the conclusion of 10 micrograms per cubic meter based on it.  That showed a reduction in lifespan of 9-11 years in consequence but we don't know who showed that.  So far, we're rolling with it but it looks kind of loose.

But calculating the costs associated with premature death caused by air pollution is complex and has resulted in very different estimates: because of the different methodologies used, the cost of air pollution related to fossil fuel consumption is estimated to be three times higher in the US than the EU.

"The existing literature is ambiguous and there are differences in the approaches adopted in EU and USA for how to account for such costs," commented Prof. Andersen. "People are willing to pay a price to reduce risks for dying prematurely, provided we have an understanding of the implications and magnitudes of such risks."

- PO

When we see much estimating, we start estivating.  Thus far it looks vague.

Note:  we're skipping over a part which demonstrated current estimates are generally rubbish but see the original article to check that for yourself.

To work out a more accurate figure, Prof. Andersen used a lifetable of 100,000 people with an age distribution that matches the current population, which showed estimated mortality rates by age. He determined the number of people expected to survive for their remaining lifetime in each age group and totaled this to give the total number of expected life-years. He then simulated the effect of long-term exposure to increased air pollution (of 10 micrograms of small particles per cubic meter) on mortality.

- PO

This segment is actually kind of trick since he's using real observations across a large sample size and we always like to see that plus the approach is different from any current calculation since it's based on years of life lost rather than a simple estimate of the number of people who died.  However, it gets squishy with that simulation of pollution's effects.  We're cautious but continuing.

The result revealed the average age of an air pollution victim is 78.9 years and their average loss of life expectancy is 9-11 years - much longer than a frequently cited estimate of 1-2 years. For comparison, the estimated loss of life years to traffic fatalities is 35-40 years. Dr. Andersen hopes that this information will inform international institutions and policy makers that want to accurately account for deaths caused by air pollution due to fossil fuel consumption.

- PO

While the mechanism used for estimation of the impact by simulation is not so clear, overall the article delivers it to the Rockhouse.  Even if his estimates are wildly wrong and are off by 50% in either direction, you still wind up paying at least five years of your life for unhealthy air and possibly or probably much more than that.

The interested student is always invited back to the original source and strongly so because it takes many years to wreck your lungs but when it's done there's not much of a way to fix them. - One Who Knows


Anonymous said...

Not sure about the language or the math
He makes a statement
The average age if an air pollution is 78.9 years old. What criteria is used to label each victim as a air pollution death.
If their life expectancy is reduced by 9-11 years that would put the average healthy life expectancy at 90 years old.
Does it separate out smokers from these calculations as smoking past the age if 40 years old will probable reduce lifespan by an estimated 10 years. Considering 15 to 25% of the population smoke regularly that would dramatically sure these numbers higher.
As with you, estimating outcomes like these have far too many variables to be little more than educated guesses

Peas InOurThyme said...

All of that is fair enough and they're confounding factors for a complex problem.

It is an educated guess, tho, and we know intuitively breathing polluted air won't do anyone any good but exactly how bad may be impossible to exactly tell.

Anonymous said...

A quick check shows a life expectancy for an average American is 78.9 years in 2016. WOW it is the same as for a person who is an air pollution victim.

Peas InOurThyme said...

I question the accuracy of the estimates as well and that's the largest reason for the article. We accept the fact there's damage from air pollution but quantifying it hasn't been all that successful.