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PM2.5 exposure possibly leads to 1.37M people’s premature death in China

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Re: PM2.5 exposure possibly leads to 1.37M people’s premature death in China

#31

Post by seanmcdirmid »

tptacek wrote: post #27

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.

Nuclear plants don't kill anyone outside of a couple of accidents, so "infinitely more" would even be correct.

However, I'm not very excited about China's nuclear power program, I don't have confidence that they aren't going to cut corners in ways that would cause a huge disaster down the line.

Re: PM2.5 exposure possibly leads to 1.37M people’s premature death in China

#32

Post by seanmcdirmid »

anexprogrammer wrote: post #20
hellofunk wrote: post #3

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

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

China isn't a huge consumer of diesel outside of trucks.

Re: PM2.5 exposure possibly leads to 1.37M people’s premature death in China

#33

Post by rockinghigh »

Retric wrote: post #12
kristianov wrote: post #7

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

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.

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.

Re: PM2.5 exposure possibly leads to 1.37M people’s premature death in China

#34

Post by adsfqwop »

stephenbez wrote: post #26

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).

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).

Re: PM2.5 exposure possibly leads to 1.37M people’s premature death in China

#37

Post by memonkey »

adsfqwop wrote: post #34
stephenbez wrote: post #26

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).

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 th…

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.

Re: PM2.5 exposure possibly leads to 1.37M people’s premature death in China

#38

Post by kurthr »

rabboRubble wrote: post #29

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/ [1] 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 gim…

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/

Re: PM2.5 exposure possibly leads to 1.37M people’s premature death in China

#39

Post by piotrjurkiewicz »

tptacek wrote: post #27

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.

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://web.archive.org/web/20150611212052/http://www.babcock...

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...

> 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".

Re: PM2.5 exposure possibly leads to 1.37M people’s premature death in China

#40

Post by stephenbez »

memonkey wrote: post #37
adsfqwop wrote: post #34

Earlier quoted context omitted.

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 th…

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.

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...) 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

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