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

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

english.pku.edu.cn

90 pointspizza58 comments

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

AKA, nanoparticles; 2.5 micrometers = 2500 nanometers.

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

https://en.wikipedia.org/wiki/Nanoparticle

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...

> 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.

subsumes ≠ AKA

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 gimmicky solutions like installing air filters at street intersections.

More needs to be done in India, China~

In the Asia-expat community, I think most of us have accurate rankings in our heads. Right now, there is a 999 reading for Delhi on aqicn, but this could be PM 10 (and I check, it is, still PM2.5 is bad at 400+). India is definitely behind China as a low-middle income country, but China is middle-high income, it isn't in the same class as India.

I think we just expected more from China especially when companies were trying to convince us that we didn't need hardship pay to work in China while it is still provided in India (the US embassy/consulates had to reinstate hardship pay in China after 2010, international recruitment at other companies is way down). China was supposed to lack the negative features of a least developed country, but that wasn't really the case when air pollution was considered; it really does effect your lifestyle (you can't go for nightly walks anymore, you are a slave to aqi readings, "don't forget to wear your face mask honey!" as my wife would say).

BTW, if I was going to work in India, I would choose Bangalore. The air seemed OK enough compared to Delhi and Mumbai.

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/

>Eastern India (Delhi)

Delhi is in Northern India, and not much to the east, AFAIK. There is plenty of land to the east of Delhi in India, before the border. And a good amount to the west too. Google "political map of India".

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

It's a small world after all.

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

Is there a good website that provides such air pollution current & forecasts for Europe or better world wide?

https://aqicn.org

In addition to my sibling commenter, there is also:

http://www.airqualitynow.eu/

However, city-specific readings are not always reliable, as they are based on a very localized meter in one particular place that can rarely reveal the overall situation for an entire city. I prefer air pollution maps that show the overall state for a big region, like the one I linked to.

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

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.

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...

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

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.

-> I'm not very excited about China's nuclear power program, I don't have confidence that they aren't going to cut corners

Then hopefully you don't live in the UK, where China is developing new designs for reactors -

http://www.telegraph.co.uk/business/2016/09/15/china-to-buil...

A chance to prove themselves with adult supervision is better than nothing.

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".

China's PM2.5 output is overwhelmingly attributed to its coal power plants, so I think it's a bit of a rhetorical stretch to call what I said an "ignorant lie". Further:

* The Chinese coal industry is built out of boiler designs that are difficult to retrofit the "clean coal" stack of technologies on

* Despite aggressive investment in filtration and treatment in the US, field studies show fluctuating (at times increasing) levels of PM2.5 pollution in cities near coal plants

* Reductions in PM2.5 matching the levels stated by the coal industry documents you're providing depend not just on expensive retrofits of existing plants, but also on careful selection of (more expensive) higher-grade coal, and on expensive ongoing upkeep of consumable filtration components

I'm not opposed to clean coal, where its efficiency and effectiveness can be demonstrated and, equally importantly, regulated. But that's not the Chinese coal industry.

> 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.

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).

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

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/

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

If we cannot rely upon HEPA ratings, then what should consumers look for if we want to take air purification seriously? Short of going out to purchase industrial air purification equipment that is purpose-made for applications like clean rooms, I don't know how to evaluate and purchase for a residential application. There are lots of pollen allergy patients who would be very happy if they could live in a PassivHaus that can be made practically airtight and pass all incoming air and circulating through an actually effective air purification system.

Get some houseplants too.

https://en.wikipedia.org/wiki/NASA_Clean_Air_Study

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

http://www.pnas.org/content/113/39/10797.abstract

easier to read:

https://www.theguardian.com/environment/2016/sep/05/toxic-ai...

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

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

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

I second this question- please post some links if anyone knows of an effective way to detect and do long-term monitoring of these in-home or at a workplace.

Beijing based startup is making "smart air quality monitor":

http://originstech.com

Found a good overview of currently available monitors:

https://cleantechnica.com/2016/07/09/home-indoor-air-quality...

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.

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.

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.

Agreed wealth is a confound, however there are several studies that control for socioeconomic status, air conditioning and smoking. These studies still observe a correlation between PM2.5 and increased all-cause mortality primarily driven by increased lung cancer and heart disease mortality. A couple studies linked below control for a few of these confounds, but there are several others too [1,2].

The causal reason is likely the fine particulate matter getting "stuck" in lung tissue and our bodies unable to remove the particles causing accumulative issues on lung function [3].

[1] http://www.nejm.org/doi/full/10.1056/nejmsa0805646

[2] http://circ.ahajournals.org/content/109/1/71.full

[3] http://www.tandfonline.com/doi/pdf/10.1080/10473289.2006.104...

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.

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.

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...

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.

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

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

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)"

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

Hah. I thought this was an article about PM2

Tbh, I thought this was about https://github.com/Unitech/pm2 . I was pretty confused.

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

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

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

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