Dear General

[Al Trego]

This is an open plea to my dearly beloved and much respected friend General U. Grant to either put up or .....

Over the past several years I have been following various threads discussing air quality and its effects on health in Chiang Mai.

Throughout this period, dear General, you have had a policy of poo pooing any and all evidence that Chiang Mai just might have a problem with the quality of our air at this time of most years. (Yes, it may not be as bad as Soot Prakan, Beijing or Timbuktoo, but that is irrelevant. We do not make our lives there.)

There is a huge amount of unimpeachable evidence from CMU, the pollution control aurhorities, the health department and many others including international organisations that the problem exists and is causing distinct health problems, loss of quality and even loss of life for many residents of this city and surroundings.

Please can you cite equivalent sources for your contentions that there is no problem. I am sure many of the members of the forum would be highly interested.

[FolkGuitar]

This is an open plea to my dearly beloved and much respected friend General U. Grant to either put up or .....

Over the past several years I have been following various threads discussing air quality and its effects on health in Chiang Mai.

Throughout this period, dear General, you have had a policy of poo pooing any and all evidence that Chiang Mai just might have a problem with the quality of our air at this time of most years. (Yes, it may not be as bad as Soot Prakan, Beijing or Timbuktoo, but that is irrelevant. We do not make our lives there.)

There is a huge amount of unimpeachable evidence from CMU, the pollution control aurhorities, the health department and many others including international organisations that the problem exists and is causing distinct health problems, loss of quality and even loss of life for many residents of this city and surroundings.

Please can you cite equivalent sources for your contentions that there is no problem. I am sure many of the members of the forum would be highly interested.

Hi Al,

Could you please give us a cite to show why the evidence from CMU, pollution control authorities and the health department are to be believed? I've lived here long enough to question all reports coming out of so called authorities. After all, TIT.

(By the way, this is NOT to endorse nor refute any information or anyone's perception of the current air quality, only the source of the stats. Personally, I only go by what my eyes tell me when I try to find Doi Suthep. I know it's here somewhere....)

[Ulysses G.]

Actually, I have never said that there is no problem and particularly at this time of year. There is a problem, but normally it is not bad enough for tourists to avoid coming here or for people in normal health to have to flee to the beaches. There are places in Thailand with much worse air pollution, but no one seems to mention them.

My big complaint is with neurotic people blowing the problem way out of proportion to the point where people start avoiding Chiang Mai for silly reasons that end up hurting everyone who lives here.

Here is one of my typical posts about the problem which I posted yesterday with some comments from another poster who is a real expert on the subject:

Priceless 2008-03-09 13:44:58 Post #451

When I mentioned rumour-mongering, I was of course not referring to you or anybody else feeling unwell. I have never disputed that a number of people feel that way and that some (e.g. asthmatics) really get ill. What peeves me is people who come up with presumably factual posts that state "Chiang Mai has the world record in air pollution" or words to that effect. This is seriously untrue and serves no other purpose than to scare people away from this lovely city. Chiang Mai would certainly do well with less polluted air, but is not by a long shot even the most polluted city in Thailand

/ Priceless

I completely support getting rid of as much air pollution as possible in Chiang Mai - and every other kind too.

I also realize that some people with lung diseases and breathing problems are quite uncomfortable at certain times of year. However, most people are bothered very little by the air here and I don't want Chiang Mai getting a reputation as somewhere to avoid in the short term when it in no way deserves it.

As Priceless has mentioned many times, some people are spreading bizarre rumors that don't reflect reality in any way. That doesn't help anyone!

[Bill97]

I recall UG writing that it does not effect him and I would have said the same thing until last year when it was exceptional. That is about how we felt over many years, not a long term study of the health effects. I only started looking at the data last year and did not hear much about it until two years ago, is there data for the past 10 years somewhere?

[Ulysses G.]

That is pretty much exactly how I feel, but I have realized for a while that at this time of year, people with breathing problems and medical conditions suffer when I feel nothing unpleasant at all.

We shouldn't forget that what happened last year was highly unusual - not in anyway typical. Some people are really paranoid about another tsunami in Phuket even though it has only happened once and might never happen again.

[FolkGuitar]

Actually, I have never said that there is no problem and particularly at this time of year. There is a problem, but normally it is not bad enough for tourists to avoid coming here or for people in normal health to have to flee to the beaches. There are places in Thailand with much worse air pollution, but no one seems to mention them.

My big complaint is with neurotic people blowing the problem way out of proportion to the point where people start avoiding Chiang Mai for silly reasons that end up hurting everyone who lives here.

Thinking about this, I realized that we had never visited Chiang Mai before moving here because of what people were writing or saying.... We were tourists and we made our plans based upon what we read or heard.

We always spent a month or two every year for 12 years down on Koh Tao diving, then finishing up with a few days or so in Bangkok before flying back to Japan. We thought about visiting Chiang Mai, but it was always summer time and everyone was always talking about how badly flooded Chiang Mai was. It was because of these reports that we never visited. Our only impression was; Chiang Mai is under water every summer. When we decided to move to LOS, it was after rainy season, so we came to Chiang Mai. That was seven years ago. Somehow, we managed to survive 'all the floods.' Oddly enough, they weren't nearly as severe as people were saying. Except of course the flooding a couple of years ago, and even that was only for a week or so.

Let us never forget 'Chicken Licken.' Let us learn from him (her?)

[Mapguy]

A couple of comments about the use of statistics in Thailand and in Beijing.

The comment has been made on this thread and on others that since this is Thailand ("TIT"), one should not believe statistics produced by the government or academics here. That is a cheap shot. In any case, it is not thought through.

There is nothing gained economically in the short term if air pollution is emphasized. It is the opposite, if anything, when you look down the road to consider the human and economic costs of illness and so on.

In the short run, governments, especially those which are focused on economic expansion, would tend to underreport pollution. I think if you are familiar with the Chiang Mai economy last year during the exceptionally nasty days of March, you will recall the panic of city and provincial authorities when Chiang Mai and some other northern provinces were quite justifiably declared "disaster areas." Well, for a spell (about two weeks) they were. The truth scared away the business; not the hyperbole: "Why take a chance?! I'll go to the beach instead, thank you!"

UG is correct to note that air pollution isn't "so bad" (at least in some forms of pollutants) most of the time for the average joe, and one would indeed hope that tourists are not frightened away. Doesn't help his business, and it doesn't help my property values. Unfortunately, in a developing economy wherein manufacturing and energy production are stressed, things might get worse rather than better. Ever wonder why Lampang air pollution numbers are quite high so often? Guess what's there! A huge power plant. And it is not just the very young or the very old or those suffering from respiratory diseases caused by other problems who are ultimately affected. There are long-term consequences for everyone, unfortunately. Does anyone recall the problem with use of asbestos? Check it out. A lot of denial there, too.

So, what brings about change? Education and enforcement, certainly, of meaningful standards and laws. Perhaps part of the answer is the pressure on economic interests to get their act together --- especially in an area that relies heavily upon tourism as a business.

Now, about Beijing. It was just honored as the " (Air) Pollution Capital of the World" due to satellite monitoring of conditions there. Well, that might or might not be the case, but there was a very interesting study done about air pollution monitoring in Beijing. Talk about fixing the numbers! Check out this site and go from there if you wish.

http://www.nytimes.com/2008/01/10/world/asia/10china.html

And there is much more to consider if you continue reading about the situation in China. Well, anyway, remember where the prevailing wind comes from in the winter --- during the high season here!!

[Ulysses G.]

Agreed.

Well said.

[anonymouse]

This is an open plea to my dearly beloved and much respected friend General U. Grant to either put up or .....

Over the past several years I have been following various threads discussing air quality and its effects on health in Chiang Mai.

Throughout this period, dear General, you have had a policy of poo pooing any and all evidence that Chiang Mai just might have a problem with the quality of our air at this time of most years. (Yes, it may not be as bad as Soot Prakan, Beijing or Timbuktoo, but that is irrelevant. We do not make our lives there.)

There is a huge amount of unimpeachable evidence from CMU, the pollution control aurhorities, the health department and many others including international organisations that the problem exists and is causing distinct health problems, loss of quality and even loss of life for many residents of this city and surroundings.

Please can you cite equivalent sources for your contentions that there is no problem. I am sure many of the members of the forum would be highly interested.

Can't we have all these topics on pollution pinned, seems to be a fresh one every other day.

And from what I've seen both UG and Priceless have given lots of info for the Bats in the Belfy brigade about the levels of pollution in CM.

[Ulysses G.]

anonymouse, that post made my day!

[john b good]

I'm not gonna get into the fine detail regarding the environmental air pollution in Chiangmai, other than to say that it is "not good & not conducive to one's good health"

What I really want to say is that there is clearly an absence of enforcement and education on the issue in Chiangmai.

Around midday yesterday I was in the soi alongside Rimping Nawarat. I was driving east away from the river and approx 75 metres from the Rimping shop some enterprising person had a BBQ of sorts going.

It was generating that much smoke which was blowing horizontally across the road (and restricting visibility) Now how many of these things (or like smoke generators) are there in and around Chiangmai. I would suggest many !

Now add in all the folk burning their rubbish and you have a whole lot of smoke.

It wouldn't take very much thought or organisation for the lovely mayor to have 3 - 4 people going around on motorcycles (with their eyes open of course) and stop at each offending smoke contraption and issue a citation (just the same as parking meter wardens to in 1st world countries)

First citation could be a warning and for each and every subsequent citation an on the spot fine of say Baht 500.00 (and receipt given)

The one thing that the authorities in the realm are exceedingly good at is talking. Very little action but a whole lot of talking.

So the problem will remain.....

[anonymouse]

I'm not gonna get into the fine detail regarding the environmental air pollution in Chiangmai, other than to say that it is "not good & not conducive to one's good health"

What I really want to say is that there is clearly an absence of enforcement and education on the issue in Chiangmai.

Around midday yesterday I was in the soi alongside Rimping Nawarat. I was driving east away from the river and approx 75 metres from the Rimping shop some enterprising person had a BBQ of sorts going.

It was generating that much smoke which was blowing horizontally across the road (and restricting visibility) Now how many of these things (or like smoke generators) are there in and around Chiangmai. I would suggest many !

Now add in all the folk burning their rubbish and you have a whole lot of smoke.

It wouldn't take very much thought or organisation for the lovely mayor to have 3 - 4 people going around on motorcycles (with their eyes open of course) and stop at each offending smoke contraption and issue a citation (just the same as parking meter wardens to in 1st world countries)

First citation could be a warning and for each and every subsequent citation an on the spot fine of say Baht 500.00 (and receipt given)

The one thing that the authorities in the realm are exceedingly good at is talking. Very little action but a whole lot of talking.

So the problem will remain.....

All well and good, fining these people 500baht for making a living, So now you have hundreds of jobless people in the Chiang Mai area, next thing they are mugging tourists and we have hundreds of threads about the terrible crime statistics in Chiang Mai

I agree with you though the authorities are very good at talking with very little action.

[Priceless]

This is an open plea to my dearly beloved and much respected friend General U. Grant to either put up or .....

Over the past several years I have been following various threads discussing air quality and its effects on health in Chiang Mai.

Throughout this period, dear General, you have had a policy of poo pooing any and all evidence that Chiang Mai just might have a problem with the quality of our air at this time of most years. (Yes, it may not be as bad as Soot Prakan, Beijing or Timbuktoo, but that is irrelevant. We do not make our lives there.)

There is a huge amount of unimpeachable evidence from CMU, the pollution control aurhorities, the health department and many others including international organisations that the problem exists and is causing distinct health problems, loss of quality and even loss of life for many residents of this city and surroundings.

Please can you cite equivalent sources for your contentions that there is no problem. I am sure many of the members of the forum would be highly interested.

I don't think anybody is denying that we have air pollution in Chiang Mai. I also do not believe that anybody denies that air pollution is detrimental to people's health, the more pollution the more detrimental. However, I seem to have seen many posts on this forum (implicitly) claiming that air pollution in Chiang Mai is somehow more dangerous than in other places. Why else would Chiang Mai have the "highest frequency of pollution-related illnesses in Thailand", when it has nowhere near the highest rate of air pollution?

I would therefore very much appreciate if you could post some references to the "huge amount of unimpeachable evidence" that you refer to, be it on the Internet, scientific litterature or journals etc. I have spent some time searching for such material, up until now without success. Until such references are given, I will continue to regard such claims as "urban legends".

This is not to say that we should not do our very best to decrease the amount of pollution, here in Chiang Mai as should be done everywhere. Unfortunately Chiang Mai is situated in a basin surrounded by mountains which makes it a high risk area for pollution, in particular if we happen to get a very persistent inversion functioning as a "lid", like we did last year

/ Priceless

[p1p]

We are not helped by people like the city clerk / deputy to the mayor, claiming that CM has the second highest rate of lung cancer in the world, (as he did last year.) He quoted no reputable source for his statistic.

I have made enquiries with a senior pathologist / former dean of the medical school as to the measurable effects on the health of the CM population, only to be told the information has been classified and can not be released. He says it is presumably because the authorities do not wish to hurt the tourist $.

[BigSnake]

[sylviex]

If this graph is anything to go by, then there are serious issues indeed, for surely the number of lung cancer patients in Chiang Mai must directly reflect on the quality of air in the province?

“Have you ever heard of the boiled frog syndrome?” asked Duangchan Charoenmuang of the Urban Development Institute Foundation, who has spent a number of years studying air particles and levels of air pollution in Chiang Mai. “If you put a frog into a bowl of boiling water it will leap out at the first opportunity, however, if you place the same frog in tepid water and slowly heat up the bowl, the frog will boil to death, and not notice the increase in water temperature at all. This is what is happening here in Chiang Mai; our air is progressively becoming dangerous and we are happily stewing in it,” she alarmingly informed a meeting attended by Vice Governor Prinya Panthong, a representative of the Lord Mayor, the head of the Chiang Mai Transport Department as well as a collection of other governmental officials at the provincial hall in February. “Because of the gradual increase in air pollution, there is no quick significant change to alarm the public. A 2.5 micron particulate matter (PM) is a type of air pollution. One micron is one thousandth of a millimetre, so we are talking about minute particles which are deadly when infiltrating the finest tissues of our lungs. The accepted average of PM 2.5 is 65 micrograms per cubic metre in a 24 hour period and 15 for an annual average, however, Chiang Mai’s air in the dry months frequently exceeds what is laid down by the United States Environmental Protection Agency (US EPA) as an acceptable level, several fold. In 1994, 33% of those living in Chiang Mai had respiratory problems; in 1999 the figure was 45%. This is a significant increase.”

Duangchan and fellow researchers were appealing to the local authorities to take immediate and swift action to combat this problem. Her solutions are that all burning within the city and other towns in Chiang Mai Province be immediately banned. That one day a week, a ‘clean air’ day is promoted, that a public transportation system be implemented immediately so that fewer vehicles are on the road and that a major campaign is launched to create public awareness.

from an article at chiangmainews.com/indepth/details.php?id=625

(pre-emptively - no, of course cannot prove those stats are correct)

[sylviex]

JOHN MACGREGOR : Chiang Mai has been blanketed in carcinogenic smoke for many weeks. For a large part of the year, Chiang Mai's air is more polluted than that of most cities. This is because of the high level of burning around the city and beyond, and the northwestern Suthep Range, which blocks the northwesterly and southeasterly winds - winds which would otherwise wash out air pollution - during the cool and rainy seasons, respectively. In addition, a drier dry season in the North means there is less rain to settle pollutants.

Thus, according to one study, in six of the seven categories of air pollution measured in both cities, Chiang Mai had higher concentrations than Bangkok - in most cases far higher concentrations. More specifically, Chiang Mai's level of particulates of less than 10 microns (

In 1999, 45% of Chiang Mai residents suffered from respiratory problems, according to Duangchan Charoenmuang, who has studied Chiang Mai's air at the Urban Development Institute Foundation. As for ultra-small particles - the

The broader Air Quality Index (AQI) is a measure of most known air pollutants. The AQI is frequently elevated above dangerous levels in Chiang Mai, on and off, for several months of the year - usually the January-March "burning season", but frequently longer. The city's AQI readings are more often than not higher than those of other Thai cities, including Bangkok.

Some of Chiang Mai's smog is carbon monoxide, nitrogen oxide and sulphur dioxide from industrial and vehicle emissions and cooking fires; and dust from building projects. The levels vary across the municipality, e.g. they are much higher at Wararot Market and along Thapae Road. But most of the "smog" is smoke, and this comes from the deliberate burning of crops and other vegetation, and of forests (often by villagers to trigger the growth of wild thob mushrooms, or by poachers to flush out game); and also from non-deliberate forest and grass fires. These smoke sources are local (Chiang Mai province), regional (northern Thailand) and international (Burma and Laos; but also the "Asian Brown Cloud" stretching from eastern China through Southeast Asia to Pakistan). No one knows proportionally how much smoke comes from each area.

As lowland agriculturalists in the North allegedly only burn selectively, and because so many forest fires are raging in the highlands, many deliberately lit, the current theory is that these highland forest fires - coupled with an abnormal cold front from China that is trapping haze in the northern valleys - are the prime source of Chiang Mai's recent pall of smoke. However, there is a certain capacity for denial and misattribution of blame in Thai officialdom, so this theory needs to be taken with a grain of salt for the moment.

In the short term, Chiang Mai's smoke gives residents coughs, headaches, sore throats, red streaming eyes, sneezing fits and more serious bronchial illnesses. It caused dozens of heart attacks in 2007. In 2003, there were 704,800 hospital cases of respiratory disease recorded in Chiang Mai province - roughly twice that of 10 years earlier. The Chiang Mai-Lamphun Air Pollution Control Project states that patients with general respiratory diseases in Chiang Mai outnumber those in Bangkok. Over the three days to March 20, 2007, the number of respiratory patients in Mae Hong Son rose from 416 to 3,541; in Chiang Rai, from 1,780 to 11,148; and in Chiang Mai from 1,370 to 4,514.

In the longer term, Chiang Mai's smoke raises the rates of lung cancer and other chronic or fatal ailments. Chiang Mai has the second-highest lung cancer rate in the world, according to Prof Sumittra Thongprasert from the Medical Ecology Department of Chiang Mai University - and higher than any other region of Thailand. The city's 139 lung cancer cases per 100,000 population is almost six times the world average.

from an article at aseanenvironment.info/News/44001908.htm

Edited March 14, 2008 by sylviex

[davidgtr]

JOHN MACGREGOR : Chiang Mai has been blanketed in carcinogenic smoke for many weeks. For a large part of the year, Chiang Mai's air is more polluted than that of most cities. This is because of the high level of burning around the city and beyond, and the northwestern Suthep Range, which blocks the northwesterly and southeasterly winds - winds which would otherwise wash out air pollution - during the cool and rainy seasons, respectively. In addition, a drier dry season in the North means there is less rain to settle pollutants.

Thus, according to one study, in six of the seven categories of air pollution measured in both cities, Chiang Mai had higher concentrations than Bangkok - in most cases far higher concentrations. More specifically, Chiang Mai's level of particulates of less than 10 microns (

In 1999, 45% of Chiang Mai residents suffered from respiratory problems, according to Duangchan Charoenmuang, who has studied Chiang Mai's air at the Urban Development Institute Foundation. As for ultra-small particles - the

The broader Air Quality Index (AQI) is a measure of most known air pollutants. The AQI is frequently elevated above dangerous levels in Chiang Mai, on and off, for several months of the year - usually the January-March "burning season", but frequently longer. The city's AQI readings are more often than not higher than those of other Thai cities, including Bangkok.

Some of Chiang Mai's smog is carbon monoxide, nitrogen oxide and sulphur dioxide from industrial and vehicle emissions and cooking fires; and dust from building projects. The levels vary across the municipality, e.g. they are much higher at Wararot Market and along Thapae Road. But most of the "smog" is smoke, and this comes from the deliberate burning of crops and other vegetation, and of forests (often by villagers to trigger the growth of wild thob mushrooms, or by poachers to flush out game); and also from non-deliberate forest and grass fires. These smoke sources are local (Chiang Mai province), regional (northern Thailand) and international (Burma and Laos; but also the "Asian Brown Cloud" stretching from eastern China through Southeast Asia to Pakistan). No one knows proportionally how much smoke comes from each area.

As lowland agriculturalists in the North allegedly only burn selectively, and because so many forest fires are raging in the highlands, many deliberately lit, the current theory is that these highland forest fires - coupled with an abnormal cold front from China that is trapping haze in the northern valleys - are the prime source of Chiang Mai's recent pall of smoke. However, there is a certain capacity for denial and misattribution of blame in Thai officialdom, so this theory needs to be taken with a grain of salt for the moment.

In the short term, Chiang Mai's smoke gives residents coughs, headaches, sore throats, red streaming eyes, sneezing fits and more serious bronchial illnesses. It caused dozens of heart attacks in 2007. In 2003, there were 704,800 hospital cases of respiratory disease recorded in Chiang Mai province - roughly twice that of 10 years earlier. The Chiang Mai-Lamphun Air Pollution Control Project states that patients with general respiratory diseases in Chiang Mai outnumber those in Bangkok. Over the three days to March 20, 2007, the number of respiratory patients in Mae Hong Son rose from 416 to 3,541; in Chiang Rai, from 1,780 to 11,148; and in Chiang Mai from 1,370 to 4,514.

In the longer term, Chiang Mai's smoke raises the rates of lung cancer and other chronic or fatal ailments. Chiang Mai has the second-highest lung cancer rate in the world, according to Prof Sumittra Thongprasert from the Medical Ecology Department of Chiang Mai University - and higher than any other region of Thailand. The city's 139 lung cancer cases per 100,000 population is almost six times the world average.

from an article at aseanenvironment.info/News/44001908.htm

Ah well, that's it then. We are all doomed to die & more than likely our chances of dying from lung cancer are 6 times worse than anyone else. <deleted> what a way to go - the old cancer. And I thought we might all be able to die peacefully in our sleep from old age because we’ve been living in a (false) paradise.

What now? I guess we should all get out & protest how are lives are being stuffed up by pollution.

You can't enjoy life anymore, unless we move to the next paradise & wait 20 years for that to be stuffed up by development too!

Then there'd be nowhere to go & our lives would have been such a waste.

Shtye what are we here for? There's nothing but doom & gloom, pollution & lung cancer everywhere.

Best to go back to the cave perhaps.

[sylviex]

Quite a touchy subject .

[Contractor]

UG says: I have realized for a while that at this time of year, people with breathing problems and medical conditions suffer when I feel nothing unpleasant at all.

People with relevant "medical conditions" just react sooner to air pollution. Your health is also at risk, despite the fact that you don't feel anything "unpleasant" at the time.

Edited March 14, 2008 by Contractor

[Priceless]

If this graph is anything to go by, then there are serious issues indeed, for surely the number of lung cancer patients in Chiang Mai must directly reflect on the quality of air in the province?

“Have you ever heard of the boiled frog syndrome?” asked Duangchan Charoenmuang of the Urban Development Institute Foundation, who has spent a number of years studying air particles and levels of air pollution in Chiang Mai. “If you put a frog into a bowl of boiling water it will leap out at the first opportunity, however, if you place the same frog in tepid water and slowly heat up the bowl, the frog will boil to death, and not notice the increase in water temperature at all. This is what is happening here in Chiang Mai; our air is progressively becoming dangerous and we are happily stewing in it,” she alarmingly informed a meeting attended by Vice Governor Prinya Panthong, a representative of the Lord Mayor, the head of the Chiang Mai Transport Department as well as a collection of other governmental officials at the provincial hall in February. “Because of the gradual increase in air pollution, there is no quick significant change to alarm the public. A 2.5 micron particulate matter (PM) is a type of air pollution. One micron is one thousandth of a millimetre, so we are talking about minute particles which are deadly when infiltrating the finest tissues of our lungs. The accepted average of PM 2.5 is 65 micrograms per cubic metre in a 24 hour period and 15 for an annual average, however, Chiang Mai’s air in the dry months frequently exceeds what is laid down by the United States Environmental Protection Agency (US EPA) as an acceptable level, several fold. In 1994, 33% of those living in Chiang Mai had respiratory problems; in 1999 the figure was 45%. This is a significant increase.”

Duangchan and fellow researchers were appealing to the local authorities to take immediate and swift action to combat this problem. Her solutions are that all burning within the city and other towns in Chiang Mai Province be immediately banned. That one day a week, a ‘clean air’ day is promoted, that a public transportation system be implemented immediately so that fewer vehicles are on the road and that a major campaign is launched to create public awareness.

from an article at chiangmainews.com/indepth/details.php?id=625

(pre-emptively - no, of course cannot prove those stats are correct)

Thank you very much for posting this interesting article. I am still on the lookout for some scientific publications but, as they say, every little bit helps. Having said that, I have a few objections to the content of the article. Please bear with me, I do not have any medical training (in this context I wish I did) but I have been working with statistics as one of my professional tools for most of my life. So, let's take a look at the article from my perspective:

1/ The graph at the top of the article obviously shows data that are now 15-20 years old. Are there no newer data, or why were these chosen?

2/ The graph shows an increase in cases of lung cancer of 25-30% over a 3 year period. Considering that cancer is a slowly developing disease this drastic increase seems very improbable, at least if caused by environmental factors. I can only guess what's behind it, but one possible explanation is a change in diagnostic methods, i.e. that the increase depends on a higher percentage of cases being detected rather than actually occurring. Another cause could of course be some kind of acute poisoning, though I have no idea what that would be.

3/ The graph also shows that during the years 1992-1994 there were ~1,800 cases of lung cancer in Chiang Mai vs ~1,300 cases in Bangkok. Considering the differences in population, that would mean a 10-20 times (1,000-2,000%!) higher frequency of lung cancer in CM. According to the Pollution Control Department (PCD) data (if one is to believe them), there is really no drastic difference in air pollution levels between Chiang Mai and Bangkok (out of 8 measuring stations in Bangkok 3 are markedly better than CM, 4 are at approximately the same level and 1, Din Daeng, is infinitely worse). Either the numbers of lung cancer cases are wrong (which I tend to believe) or there is some other major explanatory factor behind the differences.

4/ "[...]surely the number of lung cancer patients in Chiang Mai must directly reflect on the quality of air in the province?" To my eyes, this is pure nonsense! Why?

Cancer in general is a disease with many and complicated causes. However, it is fairly well known what causes lung cancer. According to the American Lung Association (http://www.lungusa.org/site/pp.asp?c=dvLUK9O0E&b=35427) 87% of cases of lung cancer are caused by smoking. If, for a moment, we assume that the same is true in Thailand it would mean that a maximum of 13% of all cases could be caused by air pollution. To achieve a 25-30% increase in the total number of cases, this would mean a 200-250% increase in the number of pollution-induced cases over a period of 3 years!!!

5/ Dr Duangchan says: "This is what is happening here in Chiang Mai; our air is progressively becoming dangerous and we are happily stewing in it". In relation to the graph slightly above this statement, the comment is rather amusing. We have supposedly had an increase in lung cancer frequency of 25-30% over just three years and nobody has noticed? On the same theme, the frequency of respiratory problems in Chiang Mai has increased from 33% in 1994 to 45% in 1999 and nobody has noticed?

6/ Secondly, is it really a fact that the air quality is "progressively becoming dangerous"? Again according to PCD data, it seems more like it staying the same or even improving. Of the 14 months since 1 January 2007, 11 have had average pollution levels under the average for the corresponding months during 2000-2008 and 3 have had higher levels (the infamous February - April of last year).

On a happier note: Dr Duangchan suggests: "that all burning within the city and other towns in Chiang Mai Province be immediately banned. That one day a week, a ‘clean air’ day is promoted, that a public transportation system be implemented immediately so that fewer vehicles are on the road and that a major campaign is launched to create public awareness". With the possible exception of the "clean air day" I think these proposals are very sensible and should implemented as soon as possible. Unfortunately I think she is overly optimistic in believing the problem can be solved "in four years", but the situation could certainly be improved

/ Priceless

[Priceless]

I recall UG writing that it does not effect him and I would have said the same thing until last year when it was exceptional. That is about how we felt over many years, not a long term study of the health effects. I only started looking at the data last year and did not hear much about it until two years ago, is there data for the past 10 years somewhere?

You find the Pollution Control Department data here: http://www.pcd.go.th/AirQuality/Regional/Q...fm?task=default

Use the scroll down menu under "Query by particular site" and you will get data for, more or less, the last ten years. PM me if you want more information, I've been long-winded enough already today

/ Priceless

[Bill97]

Thank you Priceless. That data was interesting and showed that in most of the past 9 or 10 years there were roughly 12-18 days in March with numbers over the standard of 100 and that 1999 was bad in February also. The rest of the months looked pretty good.

[Ulysses G.]

Little reason for average folks to avoid Chiang Mai.

Thank you Priceless!

[davidgtr]

Little reason for average folks to avoid Chiang Mai.

Does that mean we can all come out again?

Edited March 14, 2008 by davidgtr

[Bill97]

Little reason for average folks to avoid Chiang Mai.

Does that mean we can all come out again?

No David, we can not, only average folks can.

Edited March 14, 2008 by Bill97

[realthaideal]

Can't you see ?! When we get angry at the sky, and call each other out, that's how the terrorists win. Anger and frustration give you cancer just as surely as gray skies and red sunsets at 4:30 pm. Focus energy where it is needed and do something with it, otherwise you only aid the terrorists. Let's not be silly and raise a ruckus amongst ourselves.

[Ajarn]

UG says: I have realized for a while that at this time of year, people with breathing problems and medical conditions suffer when I feel nothing unpleasant at all.

People with relevant "medical conditions" just react sooner to air pollution. Your health is also at risk, despite the fact that you don't feel anything "unpleasant" at the time.

Maybe yes, maybe no...

[Ulysses G.]

Anyone standing in a major traffic intersection, anywhere is the world, is "breathing that stuff" and of course it is not good for you, but that scenerio is in no way specific to Chiang Mai.

[Mapguy]

Can't you see ?! When we get angry at the sky, and call each other out, that's how the terrorists win. Anger and frustration give you cancer just as surely as gray skies and red sunsets at 4:30 pm. Focus energy where it is needed and do something with it, otherwise you only aid the terrorists. Let's not be silly and raise a ruckus amongst ourselves.

Say WHAAATTTTTT???!!!