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Comment by mikeyouse | Hacker News Reader

PM2.5 smog is literally poisonous.. From Wiki[1]:

    The smaller PM2.5 were particularly deadly, with a 36%
    increase in lung cancer per 10 μg/m3 as it can penetrate
    deeper into the lungs

And...

    An increase in estimated annual exposure to PM 2.5 of
    just 5 µg/m3 was linked with a 13% increased risk of heart
    attacks.

So 36% increase in lung cancer per 10μg/m3 and a 13% increase in heart attacks from 5μg/m3.

The level in Beijing right now is 250μg/m3. It maxed at over 360μg/m3 in the past 48 hours.[2]

People are literally being killed by Beijing's air quality as we speak, should we temper our language to not appear biased?

[1] - https://en.wikipedia.org/wiki/Particulates

[2] - http://aqicn.org/city/beijing/us-embassy/

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It's worth remembering that a 36% increase of a marginal risk is still marginal. That number doesn't mean anything unless you know the original risk.

Exactly. the typical risk of cancer is measured in "per million", so having a 36% risk does not mean "people are getting killed as we speak".

At 35% per 10µg, it's actually about a 900% increase in lung cancer risk. That's a significant effect, because it means 900% more people will get lung cancer on average. People are getting killed, it's just hard to say how many without better numbers.

> At 35% per 10µg, it's actually about a 900% increase in lung cancer risk.

You can extrapolate linearly such numbers, it makes absolutely no sense. This is not a math class, we are talking about clinical effects with actual thresholds.

"35% per 10µg" expresses a linear relationship. If someone says that's what it is, I'm going to assume they measured a linear relationship. It makes perfect sense if that is indeed the reality, and I see no reason why it cannot be.

Unless you've got some actual conflicting data, it just sounds like you have unfavorable agenda.

Even if it's a linear relationship, it can only exist within the demonstrated range. You should know that not everything is linear when you go outside of the range you have studied.

So unless proven this linear relationship is valid across all the spectrum (which is obviously is not), then you should take whatever is written with a big grain of salt and thing twice about it before making over simplistic assumptions.

Lung cancer has a normal occurrence of something like 60 in 100,000.

If we are as conservative as we can be and say the increase is only 36% from all of these smog days, that would mean that the rate should increase to 82/100,000.

Beijing's population is ~21 million. The 22 / 100,000 increase from the base rate would mean an additional 5,000 lung cancer deaths in Beijing due to the smog. That's the minimum. The more realistic number is surely an order of magnitude or more higher -- this level of pollution is unprecedented in modern times.

Again, what is the current data showing Beijing is far worse than the national average for lung cancer (because pollution has been pretty bad there for a long time already) ?

I see assumptions, estimations but no hard facts to support anything, right now.

I mean, you could try looking literally anywhere.. This is a well known problem;

From 2014:

http://www.bloomberg.com/bw/articles/2014-02-28/rates-of-lun...

    In 2002, for every 100,000 men living in Beijing, 49
    had lung cancer. By 2010, that number had risen 
    more than 50 percent, to 75. Women in China are 
    less likely to smoke and so have lower rates of the 
    disease. But among those living in Beijing, a similar 
    sharp rise in lung cancer cases occurred over the 
    last decade. In 2002, for every 100,000 women 
    living in Beijing, 30 had lung cancer; by 2010, that 
    number had also risen more than 50 percent, to 46.

So the rate in the US is 60/100,000 -- As of 2010, in Beijing, the rate is closer to 121/100,000. Does a 100% increase in risk change your opinion of these 'marginal' deaths? For a population of 21M, this is equivalent to ~13,000 additional lung cancer deaths.

Problem is, lung cancer rates are increasing all around the globe, so that does not answer anything regarding "are the lung cancer rate in Beijing unusual vs the rest of the world?".

But at least that's a start for a proper discussion.

And please do not compare a US rate that includes countryside and cities with a city-based rate in China. That's not a relevant comparison at all. Rates vary wildy state by state in the US :

http://www.cdc.gov/cancer/lung/statistics/state.htm

As you can see the average in some states go to 90+ in the US.

The rate of lung cancer for the State of Kentucky 2007-2011 is 122/100 000 (http://www.cancer.org/acs/groups/content/@editorial/document...). I don't see that making the headlines in newspapers anywhere.

Didn't you just warn me about comparing countryside to cities in China? In any case, the high levels in Kentucky are the legacy of coal country, which China would be wise to avoid. It also doesn't help that China's rate is increasing year-over-year along with their population that's already 5x the entire state of Kentucky. I literally can't fathom why you're trying to minimize the impact of dirty air in Beijing.

From your link in [1]

> The meta-analyses showed a statistically significant association between risk for lung cancer and PM10 (hazard ratio [HR] 1·22 [95% CI 1·03–1·45] per 10 μg/m3). For PM2·5 the HR was 1·18 (0·96–1·46) per 5 μg/m3.

The increase of risk of lung cancer was NOT significant with PM2.5 ratio. Only with PM10.

So pick any other study that shows a significant link.. There is no ambiguity within the scientific community about the link.. Why are you so intransigent about this?

PM2.5 at 300 is equivalent to 25 cigarettes per day, and has the same associated risks:

http://i.imgur.com/YP5FeWp.jpg

From: http://ehp.niehs.nih.gov/1103639/

Come on, the article referred "you could get sick just by standing in the street" - if that's not hyperbole, I don't know what that is.

> with a 36% increase in lung cancer per 10 μg/m3 as it can penetrate deeper into the lungs

Observational study. That says everything, it does not account for all variables that have to be taken in account and therefore the effect cannot be isolated.

> An increase in estimated annual exposure to PM 2.5 of just 5 µg/m3 was linked with a 13% increased risk of heart attacks.

Annual exposure. Not standing in the streets for 5 minutes like the article suggests.

Yes, we should temper our language and use Good Science and not Sensationalism.

Have you ever been there? If you want to talk about science, then define "sick" fisrt. For most people, frequently coughing would be considered as "sick". Note that we are not discussing disease, we are talking about sickness, which I think is a less rigorous word sometimes referring to "not feeling good".

I was born in Beijing and have been living there for more than two decades. And yes, I feel bad when I was exposed under that environment: I can hardly breathe, I coughed a lot and felt itchy in every inch of my skin. If you think that is not "getting sick", then well, welcome to Beijing.

> Have you ever been there?

As a matter of fact, I have, and several times. Don't assume I know nothing of what I am talking about please.

Please show me the stats of lung cancer in Beijing vs other parts of the world. I'd like to see how much the reality stands out vs the assumptions people make.

> If you think that is not "getting sick", then well, welcome to Beijing.

I was not talking about discomfort (that, I have noticed on every trip I did there) but this particular article makes blatant claims with absolutely no data to back them up, which was exactly the point of my post: allegations do not create facts.

https://www.google.com/search?q=stats+of+lung+cancer+in+Beij...

"Come on, the article referred "you could get sick just by standing in the street" - if that's not hyperbole, I don't know what that is."

Actually, that's understatement. You don't even need to be standing in the street.

Air circulates everywhere, both indoor and out. Sure, you can try and seal your windows, and run air purifiers in your home. But what about when you're at work, or at a restaurant, or any other non-home place?

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