
PM2.5 exposure possibly leads to 1.37M people’s premature death in China - pizza
http://english.pku.edu.cn/news_events/news/research/5076.htm
======
mcguire
For anyone else who doesn't immediately get the acronym,

" _Fine particles (PM2.5) are 2.5 micrometers in diameter or smaller, and can
only be seen with an electron microscope. Fine particles are produced from all
types of combustion, including motor vehicles, power plants, residential wood
burning, forest fires, agricultural burning, and some industrial processes._ "

[https://airnow.gov/index.cfm?action=aqibasics.particle](https://airnow.gov/index.cfm?action=aqibasics.particle)

~~~
toufka
AKA, nanoparticles; 2.5 micrometers = 2500 nanometers.

~~~
cheiVia0
> Nanoparticles are particles between 1 and 100 nanometers in size.

[https://en.wikipedia.org/wiki/Nanoparticle](https://en.wikipedia.org/wiki/Nanoparticle)

~~~
toufka
So where exactly then do 'nanoparticles' fall on the PM exposure list then?
The standard measurements separate 'small' (<2.5 micron) particulate from
'big' (<10 micron) particulate. 'Small' things entirely subsume the
nanoparticle definition.

PM2.5 exposure is exposure to particles with their largest length being less
than 2500 nanometers. The link says PM2.5 include, "combustion particles,
organic compounds, metals, etc." \- wherein those classes of particulate
indisputably qualify as nanoparticles.

If you want to be really pedantic, we could instead say that PM2.5 include
'nanoparticles, clumps of nanoparticles, irregularly shaped nanoparticles, and
fine particles'. But I suspect most people do not have common mental
distinction between a 'fine' particle and a 'nanoparticle', even though they
are (physiologically) more similar to each other in most regards than they are
to larger, visible particles, hence the difference in measuring both PM10 and
PM2.5 atmospheric particulate [1].

Regardless, the article is talking about a huge amount of pollution,
indistinguishable from 'nanoparticles' at the point of measurement, that have
caused health problems for a truly massive number of humans.

[1]
[https://en.wikipedia.org/wiki/Particulates#Size.2C_shape_and...](https://en.wikipedia.org/wiki/Particulates#Size.2C_shape_and_solubility_matter)

> Similarly, so called fine PM, (often referred to as PM2.5), tend to
> penetrate into the gas exchange regions of the lung (alveolus), and very
> small particles (< 100 nanometers) may pass through the lungs to affect
> other organs.

> The smallest particles, less than 100 nanometers (nanoparticles), may be
> even more damaging to the cardiovascular system. Nanoparticles can pass
> through cell membranes and migrate into other organs, including the brain.
> Particles emitted from modern diesel engines (commonly referred to as Diesel
> Particulate Matter, or DPM) are typically in the size range of 100
> nanometers (0.1 micrometer). These soot particles also carry carcinogens
> like benzopyrenes adsorbed on their surface.

~~~
the8472
subsumes ≠ AKA

------
rabboRubble
Try comparing air quality in [0] Beijing and [1] Delhi. Most days you will
find Indian air pollution far worse than the air pollution in Beijing.

[0] [http://aqicn.org/city/beijing/](http://aqicn.org/city/beijing/) [1]
[http://aqicn.org/city/india/new-delhi/us-
embassy/](http://aqicn.org/city/india/new-delhi/us-embassy/)

Not letting China off the hook, but India is hardly ever mentioned and their
problems are worse. India has been unable to implement effective policies and
instead are looking toward gimmicky solutions like installing air filters at
street intersections.

More needs to be done in India, China~

~~~
kurthr
If you're looking for a global view, I recommend the world-view of the AQICN
forecast. You can really see where the hot spots are and how they distribute
particulates to other areas. Central China (Chongqing) and Eastern India
(Delhi) are particularly bad. Europe really isn't bad (even when it goes over
100... it's not 600-999) and the west coast of the US gets hit by China smog.

[http://aqicn.org/forecast/model/cams-
world/](http://aqicn.org/forecast/model/cams-world/)

~~~
seanmcdirmid
Damn, I didn't realize the Aleutians got hit so badly by Asian pollution.

~~~
mcguire
It's a small world after all.

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hellofunk
While China is somewhat the poster child for modern air pollution, do not
overlook that PM2.5 and PM10 exposure is also very bad in many parts of
Europe, SE Asia, and large American cities. The Netherlands occasionally
experiences a haze that is quite visible and smokey-smelling, in fact tomorrow
will be one of the worst days of the year for PM exposure in NW Europe:

[http://www.temis.nl/aqi/aqi_nl.html](http://www.temis.nl/aqi/aqi_nl.html)

~~~
anexprogrammer
I wonder how much of that stems from the efforts to promote diesels over
petrol for CO2 reasons.

~~~
kwhitefoot
CO2? The energy content of the fuel is roughly the same and the are both made
of hydrocarbon chains with similar proportions of carbon and hydrogen. The
principal difference being that petrol is shorter chains C8.. C11 and diesel
is C13..C18. So how does using diesel reduce the emission of CO2? I understand
that diesels are generally a little more efficient than petrol engines but
that doesn't seem to be enough to claim any serious reduction on CO2
emissions.

~~~
anexprogrammer
I don't disagree, but there was a Europe wide effort in the late 90s to
encourage diesels following Kyoto. The resulting tax changes on both vehicles
and fuel led to a huge growth in diesels. They went from a minority 10% of
vehicles to over half.

Only later did awareness of particulates grow.

Some background: [https://www.theguardian.com/environment/2015/sep/22/the-
rise...](https://www.theguardian.com/environment/2015/sep/22/the-rise-diesel-
in-europe-impact-on-health-pollution)

------
tptacek
This is unsurprising and in large part traceable to China's domestic coal
consumption. When people say that coal power plans routinely kill orders of
magnitude more people than nuclear plants ever have, this is what they're
talking about.

~~~
piotrjurkiewicz
Most of PM and other harmful smog components, like SOx, NOx and organic
compounds, came from:

1\. Transportation emissions, especially diesel engines.

2\. Individual heating of buildings (using coal, oil or biomass).

This is because exhaust fumes are mostly not being filtered in these cases.

Coal power plants have advanced filter systems, which can reduce pollutants by
more than 99% in some cases.

[http://i.imgur.com/dsNgDvn.png](http://i.imgur.com/dsNgDvn.png)

[http://web.archive.org/web/20150611212052/http://www.babcock...](http://web.archive.org/web/20150611212052/http://www.babcock.com/library/documents/br-1886.pdf)

[http://link.springer.com/article/10.1007/s40789-014-0001-x](http://link.springer.com/article/10.1007/s40789-014-0001-x)

Moreover, in power plants, coal burns in a much more optimal conditions, what
results in less pollutants being generated.

[https://friendsofscience.org/assets/documents/FoS_BurningQue...](https://friendsofscience.org/assets/documents/FoS_BurningQuestions_Health_Coal_Wildfires_Jan2015.pdf)

> According to Environment Canada, coal-fired power plants in Alberta in 2011
> emitted only 0.4% of PM2.5 of human-made emissions (excluding wildfires).

But somehow most of the bashing by media, green/left politicians and
'ecological' organizations is targeted at coal power plants, instead of real
pollution sources.

And ignorants enforce this lies, by repeating that "coal power plans routinely
kill orders of magnitude more people than nuclear plants".

~~~
seanmcdirmid
> And ignorants enforce this lies, by repeating that "coal power plans
> routinely kill orders of magnitude more people than nuclear plants".

We can enumerate everyone who has been killed in a nuclear plant accident
since the plants themselves do not emit any radiation or pollution when they
are generating electricity. Nuclear power only has the problem of safety (keep
bad accidents from occurring) and waste disposal, while coal plants pollute
continuously, and emit much more radiation than a nuclear power plant (and
even its waste).

The coal plants in China do not have any sophisticated environmental features
like the ones in the west. Additionally, the burn much dirtier coal (mined in
China) than the much cleaner coal that can be mined in say, West Virginia or
Australia.

------
stephenbez
Does anyone know how much the negative health effects of living near a highway
can be mitigated by using a plug-in HEPA filter?

I'm considering moving to an apartment 200 feet from the 101 (8 lane total
highway).

~~~
adsfqwop
It's hard to put a straight number on it, other than that "it will most likely
reduce the negative effects".

A standardized HEPA filter removes 99.97% of particles down to PM0.3. How much
it cleans the air in the room in the end depends on many factors, but in a
small room and a decent filter you can expect a significant reduction in
pollution.

So yes, if you want less pollution, a HEPA filter will deliver it in a
theoretical range of zero to 99.97% purification, depending on the variable
factors of room size, air circulation, purifier air flow and so forth.

A properly sized purifier will circulate all air in a room several times per
hour, so in practice you can expect a good cleanup of particulates (perhaps
around 80%) in a fairly short period of time (less than an hour).

~~~
memonkey
I just want to point out that the HEPA ratings are pretty lax on how much and
what they are effectively cleaning in the air. Pretty much everybody can use
the word HEPA and it not mean that much if they are, for example, using an
ionizer that essentially just makes the particles 'sticky' while putting them
back in the air.

Source: I work at a top international air purification company.

~~~
stephenbez
Thanks. Do you have any recommendations on what to look for when buying a
filter?

I was planning on buying a filter labelled True HEPA from a well known
company, that uses a fan and not ionization, and being sure to replace the
filter as directed.

The HEPA standard, ensures PM0.3 are filtered out. But this article
([http://now.tufts.edu/articles/big-road-blues-pollution-
highw...](http://now.tufts.edu/articles/big-road-blues-pollution-highways))
says ultrafine particles (PM0.1) are the biggest health risk. Do you know if
any filters remove ultrafine particles?

Wikipedia seems to suggest that most do: "Diffusion predominates below the 0.1
μm diameter particle size. Impaction and interception predominate above 0.4
μm. In between, near the most penetrating particle size (MPPS) 0.3 μm, both
diffusion and interception are comparatively inefficient. Because this is the
weakest point in the filter's performance, the HEPA specifications use the
retention of these particles to classify the filter"
[https://en.wikipedia.org/wiki/HEPA](https://en.wikipedia.org/wiki/HEPA)

~~~
memonkey
It is pretty difficult to filter out ultra fine particles anyway and some of
the best air purifiers can claim to do a lot. Obviously, you will be breathing
that stuff every day and unless the air around you is seriously affecting your
health, you don't need a high end air purifier. This is my opinion, but unless
you have allergies or asthma, most top of the line air filtration systems
won't have much of an impact on your day to day and I would personally suggest
any $250-$500 range air purifier. This content in this article[1] does a
really good job at comparing air purifiers but they suggest an ionizer which
can have negative effects.

Things to look out for: \- No ionizer. \- No uv light. \- True HEPA is fine
but if they've trademarked or registered their HEPA brand (HyperHEPA,
HEPASilent), I would ask them more about what that means and they should
provide a pretty good answer within the context.

1\. [http://thesweethome.com/reviews/best-air-
purifier/](http://thesweethome.com/reviews/best-air-purifier/)

~~~
chillwaves
Why no UV? Seems like it couldn't hurt.

------
clumsysmurf
Also, some of these particles enter the brain directly through the olfactory
nerve.

[http://www.pnas.org/content/113/39/10797.abstract](http://www.pnas.org/content/113/39/10797.abstract)

easier to read:

[https://www.theguardian.com/environment/2016/sep/05/toxic-
ai...](https://www.theguardian.com/environment/2016/sep/05/toxic-air-
pollution-particles-found-in-human-brains-links-alzheimers)

~~~
pizza
Crikey, that is a particularly sensible realization that is also quite
alarming.

------
ourmandave
I work <10' away from the dept laser printer all day. Talk of nano particles
makes me worry.

[https://en.wikipedia.org/wiki/Toner#Health_risks](https://en.wikipedia.org/wiki/Toner#Health_risks)

------
myth_drannon
Is there a way to measure it with a simple and cheap device?

~~~
GrumpyYoungMan
It's been a while since I last researched it but the least expensive unit I've
saw at the time that was reportedly accurate is Dylos DC1100 monitors for
~$200-$300, depending on the sensitivity and options desired. However, I never
got around to purchasing one so I can't vouch for it personally.

~~~
dxhdr
I've got a Dylos DC1100 Pro and it seems to work great, however I don't have a
solid way of verifying the accuracy of its measurements. Supposedly it's one
of the most accurate devices available at that price.

Empirically it works; running a HEPA filter in a closed room for 15 minutes
will eliminate almost all particle readings. Cooking bacon in the kitchen will
make the meter read 100x higher than normal, etc. I'd recommend buying one if
you're interested in monitoring air quality, if anything it will be useful in
giving relative quality measurements.

------
reasonattlm
The challenge in linking air pollution to age-related disease and mortality
risk lies in the confounding correlation with wealth. There are plausible
physical mechanisms involving, for example, increased levels of inflammation
resulting from high levels of particulate air pollution, but regions with
lower levels of air pollution tend to have much wealthier populations, and it
is well known that wealth correlates with lower mortality and greater life
expectancy, both for individuals and across societies as a whole.

~~~
mikeash
Is clean air really correlated with wealth in China? The wealthy Chinese are
generally in big cities which is where the terrible pollution is found.

~~~
et-al
With money, you can outfit your home and workplace with air filters and own a
weekend villa further away from the smog. You're still exposed, but at a much
lesser amount than the guard who has to stand outside all day.

See also: [http://www.nytimes.com/2011/11/05/world/asia/the-
privileges-...](http://www.nytimes.com/2011/11/05/world/asia/the-privileges-
of-chinas-elite-include-purified-air.html)

------
tudorw
another good reason to find space for more trees in urban developments;
[http://www.fs.fed.us/nrs/pubs/jrnl/2013/nrs_2013_nowak_002.p...](http://www.fs.fed.us/nrs/pubs/jrnl/2013/nrs_2013_nowak_002.pdf)

------
kristianov
For reference, it is one in a thousand (Chinese population is ~1.4B).

~~~
Retric
That's 1:1,000 per year so a much higher percentage of overall deaths. On the
order of ~7% of all deaths in china assuming 1/1000 * ~70 year life
expectancy.

~~~
rockinghigh
Death rate in China is 7.7 deaths/1,000. So 1/1,000 caused by pollution would
be closer to 13% of all deaths.

~~~
Retric
Wow, China's population must be aging really quickly.

~~~
TheDong
Interestingly they're aging at 1 year per year, which is only a tiny bit
slower than the people who live high in mountains who age at 1 year + epsilon
(where epsilon is gravitational time dilation) per sea-level-year

~~~
TheDrizzle43
I was curious how much altitude would affect aging so I did a quick google
search. "The atomic clock calculated that for every 12 inches of elevation, 90
billionths of a second are added to a lifetime (79 years)"

------
tonetheman
All I could think of was some node package manager is killing people in
China?...

~~~
k_sh
Hah. I thought this was an article about PM2

------
XCSme
Tbh, I thought this was about
[https://github.com/Unitech/pm2](https://github.com/Unitech/pm2) . I was
pretty confused.

~~~
eatbitseveryday
"PM2.5" is a standard term[1,2], along with "PM10".

[1]
[https://www3.epa.gov/ttn/amtic/amticpm.html](https://www3.epa.gov/ttn/amtic/amticpm.html)

[2]
[https://cfpub.epa.gov/airnow/index.cfm?action=aqibasics.part...](https://cfpub.epa.gov/airnow/index.cfm?action=aqibasics.particle)

