WHO agency says air pollution causes cancer (Update 2)

by Maria Cheng
This is a May 7, 2013 file photo of a foreign tourist wearing a mask walks in front of Tiananmen Gate on a polluted day in Beijing, China. What many commuters choking on smog have long suspected has finally been scientifically validated: air pollution causes lung cancer. The International Agency for Research on Cancer declared on Thursday that air pollution is a carcinogen, alongside known dangers such as asbestos, tobacco and ultraviolet radiation. (AP Photo/Alexander F. Yuan, File)

What many commuters choking on smog have long suspected has finally been scientifically validated: air pollution causes lung cancer.

The International Agency for Research on Cancer declared on Thursday that air pollution is a carcinogen, alongside known dangers such as asbestos, tobacco and ultraviolet radiation. The decision came after a consultation by an expert panel organized by IARC, the cancer agency of the World Health Organization, which is based in Lyon, France.

"The air most people breathe has become polluted with a complicated mixture of cancer-causing substances," said Kurt Straif, head of the IARC department that evaluates carcinogens. He said the agency now considers pollution to be "the most important environmental carcinogen," ahead of second-hand cigarette and cigar smoke.

IARC had previously deemed some of the components in air pollution such as diesel fumes to be carcinogens, but this is the first time it has classified air pollution in its entirety as cancer causing.

The risk to the individual is low, but Straif said the main sources of pollution are widespread, including transportation, power plants, and industrial and agricultural emissions.

Air pollution is a complex mixture that includes gases and particulate matter, and IARC said one of its primary risks is the fine particles that can be deposited deep in the lungs of people.

"These are difficult things for the individual to avoid," he said, while observing the worrying dark clouds from nearby factories that he could see from his office window in Lyon on Wednesday. "When I walk on a street where there's heavy pollution from diesel exhaust, I try to go a bit further away," he said. "So that's something you can do."

The fact that nearly everyone on the planet is exposed to outdoor pollution could prompt governments and other agencies to adopt stricter controls on spewing fumes. Straif noted that WHO and the European Commission are reviewing their recommended limits on air pollution.

Previously, pollution had been found to boost the chances of heart and respiratory diseases.

The expert panel's classification was made after scientists analyzed more than 1,000 studies worldwide and concluded there was enough evidence that exposure to outdoor air pollution causes lung cancer.

In 2010, IARC said there were more than 220,000 lung cancer deaths worldwide connected to air pollution. The agency also noted a link with a slightly higher risk of bladder cancer.

Straif said there were dramatic differences in air quality between cities around the world and that the most polluted metropolises were in China and India, where people frequently don masks on streets to protect themselves. China recently announced new efforts to curb pollution after experts found the country's thick smog hurts tourism. Beijing only began publicly releasing data about its air quality last year.

"I assume the masks could result in a reduction to particulate matter, so they could be helpful to reduce personal exposure," Straif said. But he said collective international action by governments was necessary to improve air quality.

"People can certainly contribute by doing things like not driving a big diesel car, but this needs much wider policies by national and international authorities," he said.

Other experts emphasized the cancer risk from pollution for the average person was very low—but virtually unavoidable.

"You can choose not to drink or not to smoke, but you can't control whether or not you're exposed to air pollution," said Francesca Dominici, a professor of biostatics at Harvard University's School of Public Health. "You can't just decide not to breathe," she said. Dominici was not connected to the IARC expert panel.

A person's risk for cancer depends on numerous variables, including genetics, exposure to dangerous substances and lifestyle choices regarding issues such as drinking alcohol, smoking and exercising.

Dominici said scientists are still trying to figure out which bits of pollution are the most lethal and called for a more targeted approach.

"The level of ambient pollution in the U.S. is much, much lower than it used to be, but we still find evidence of cancer and birth defects," she said. "The question is: How are we going to clean the air even further?"

Factfile on air pollutants

Here is a factfile on health-damaging atmospheric pollutants, following a determination on Thursday by the World Health Organisation (WHO) that outdoor air pollution is a leading cause of cancer:

TOLL

According to WHO estimates, urban outdoor air pollution causes 1.3 million deaths globally every year.

Nearly a quarter of a million of these deaths are caused by lung cancer.

PARTICULAR MATTER (PM)

These are microscopic particles generated by coal, oil and forest fires, but also by natural sources, including volcanoes and dust storms.

PM is so light that it can float on air. Some particles are so small that they can penetrate deep in the lungs and even cross into the bloodstream.

The components include sulphate, nitrates, ammonia, sodium chloride, carbon and mineral dust. They may also carry traces of heavy or toxic metals such as arsenic, cadmium, nickel and mercury.

Chronic exposure contributes to cardiovascular and respiratory diseases as well as lung cancer.

PM is divided into two categories: PM10, which comprises particles between 2.5 and 10 thousandths of a millimetre, or micrometres; and PM2.5, which is smaller than 2.5 micrometres—about a 30th the width of a human hair.

PM2.5 is estimated to reduce life expectancy in the European Union by more than eight months, according to the European Environmental Agency (EEA).

Exposure to even low levels of PM2.5 during pregnancy increases the risk of a baby with a low birthweight, The Lancet Respiratory Journal reported this week.

OZONE (O3)

In the stratosphere, this triple-atom molecule of oxygen is naturally occurring and protects us from the Sun's ultra-violet radiation.

At ground level, where it is formed in a chemical reaction between sunlight and exhaust gases, ozone is a component of photochemical smog.

High ozone levels can cause breathing problems, trigger asthmatic attacks and worsen respiratory disease.

The EEA says half the EU population in urban areas may have been exposed to levels exceeding EU targets.

OTHERS

Several other pollutants, also the residues of combustion or the result of reactions between exhaust and atmospheric gases, are a major concern:

They include the smog ingredient nitrogen dioxide (NO2); sulphur dioxide (SO2); carbon monoxide (CO); and a variety of heavy metals.

SOURCES: WHO, EAA, International Agency for Research on Cancer (IARC)

More information: www.iarc.fr/en/publications/books/sp161/index.php

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dogbert
1 / 5 (16) Oct 17, 2013
A meta-analysis of 1000+ studies leads to the conclusion that air pollution causes lung cancer.

To support that conclusion, the IARC noted that they had already determined that there were 220,000 lung cancer deaths connected to air pollution in 2010.

Never let science hinder the PC.
Anonym
1.8 / 5 (15) Oct 17, 2013
Wow, this sounds like a big deal, then you get the punchline: 220,000 deaths out of a population of 7 billion. Are we really supposed to restructure industrial society to solve this fly speck of a problem? Wouldn't it be better to start our war on mortality with a problem that is well within our ability to address, such as the fact that several hundred thousand people (in the US alone) die annually because of healthcare mistakes: doctors' errors made in the prescription of drugs, drug combinations, infections acquired in hospitals, botched surgeries, and so forth?

The tenor of this article reminds a little of the "climate change"(TM) hysteria: the "problem" is an academic construct fitted to a desired solution. The desired solution --- limiting industrial growth and resource allocation --- arises from a Malthusian fear of overpopulation, or perhaps, a latent (or not so latent) racist fear of overpopulation by the "wrong" kind of people.
Lurker2358
1.9 / 5 (14) Oct 17, 2013
Increasing penalties for drunk driving, such as faster and longer prison sentences, would significantly decrease the Death rate and maiming rate in the U.S. Currentely, there are 10,000 alcohol related fatal auto accidents in the U.S. each year, with another 30,000 injuries.

Also, banning cigarettes outright would begin to cut into removing a large number of second-hand smoke related illnesses, including cancers. Thankfully, the U.S. is headed in that direction, by banning cigarettes on government property and in restaurants.

Getting rid of these evils would greatly improve out economy by reducing medical bills and expenses to insurance and government programs, as well as improving productivity at work, and the over all quality of life of the average person.

I don't care what smokers or drinkers think. Think about their victims, who did the right thing and died or were maimed anyway, because of these people's harmful, selfish pleasures.
Sinister1811
2.6 / 5 (12) Oct 17, 2013
A meta-analysis of 1000+ studies leads to the conclusion that air pollution causes lung cancer.

Never let science hinder the PC.


Of course it does. People die all the time from respiratory illness from soot, smog and crap in the air.
dogbert
1 / 5 (14) Oct 18, 2013
Sinister1811,

In quoting me, you left out an important quote from the article:
My quote: To support that conclusion, the IARC noted that they had already determined that there were 220,000 lung cancer deaths connected to air pollution in 2010.

Then you say:
Your statgement: Of course it does. People die all the time from respiratory illness from soot, smog and crap in the air.

When the article claims to count the number of people who die of lung cancer.

The article does not mention COPD, asthma, etc. and does not claim to count deaths from that. My comment did not discuss deaths from respiratory failure either.

(Quoting is suddenly not working and even quote marks are being stripped.)
aroc91
1.8 / 5 (5) Oct 18, 2013
"Also, banning cigarettes outright would begin to cut into removing a large number of second-hand smoke related illnesses, including cancers. Thankfully, the U.S. is headed in that direction, by banning cigarettes on government property and in restaurants.

Getting rid of these evils would greatly improve out economy by reducing medical bills and expenses to insurance and government programs, as well as improving productivity at work, and the over all quality of life of the average person.

I don't care what smokers or drinkers think. Think about their victims, who did the right thing and died or were maimed anyway, because of these people's harmful, selfish pleasures."

Yeah, because alcohol prohibition worked soooo well. /sarcasm
depth13
2.5 / 5 (13) Oct 21, 2013


To support that conclusion, the IARC noted that they had already determined that there were 220,000 lung cancer deaths connected to air pollution in 2010.

Never let science hinder the PC.


You are an ignorant and arrogant fool . You twisted this sentence into spreading doubt in the article, If you don't know about the way to determine causation why do you spout nonsense here .
dogbert
1 / 5 (14) Oct 21, 2013
depth13: You are an ignorant and arrogant fool . You twisted this sentence into spreading doubt in the article, If you don't know about the way determine causation why do spout nonsense here .

You show your own ignorance and foolishness. They simply made up that figure. That does not represent science, that is simply fraudulent political pandering.

This whole article is simply fraudulent political pandering. The statement that they had already determined there were 220,000 lung cancer deaths connected to air pollution in 2010 is the most egregious example.
depth13
2.4 / 5 (14) Oct 21, 2013

You show your own ignorance and foolishness. They simply made up that figure. That does not represent science, that is simply fraudulent political pandering.

This whole article is simply fraudulent political pandering. The statement that they had already determined there were 220,000 lung cancer deaths connected to air pollution in 2010 is the most egregious example.


Do you have the ability to read. Are u an ignorant fool. What is your qualification to comment on a study?
You read a news article here and you think you have the ability to give a opinion . stop spouting nonsense.
dogbert
1 / 5 (14) Oct 21, 2013
depth13,
Why don't you stop lauding nonsense as if it were science?

BTW, insulting someone is a poor substitute for rational discourse.
depth13
2.2 / 5 (13) Oct 21, 2013
depth13,
Why don't you stop lauding nonsense as if it were science?

BTW, insulting someone is a poor substitute for rational discourse.


A rational discourse is possible only when someone offers constructive criticism not where crazy talk is used like in your first post. My response was for your crazy nonsense in your post, since clearly you are not capable of offering rational thoughts.
dogbert
1 / 5 (13) Oct 21, 2013
depth13,
I recognize now that you really believe just making up figures is OK.

I'll not waste any more of my time trying to convince you that scientific fraud is not OK.
depth13
2.2 / 5 (12) Oct 21, 2013
depth13,
I recognize now that you really believe just making up figures is OK.

I'll not waste any more of my time trying to convince you that scientific fraud is not OK.


since you clearly read their study and looked at their statistics and reasoning enlighten me the flaws in their method which resulted in their made up figures.