An investigation conducted by New Zealand’s 60 Minutes current affairs program titled To Die For has found high levels of chlorpyrifos pesticide in the Downtown Inn, the Chiang Mai hotel linked to the deaths of at least seven tourists earlier this year (See: Lost smiles in LOS as Thailand travel tragedies website goes live).
60 Minutes reporter Sarah Hall traveled to Chiang Mai and stayed at the Downtown Inn in the Night Bazaar section of the city and took swab samples from the hotel back to New Zealand for analysis, with further tests conducted in Italy.
First produced in 1965 by Dow Chemical Company, chlorpyrifos, an organophosphate, is a popular ingredient in flea collars and shampoo for dogs. It is also used in the manufacture of cockroach pesticides, termite treatment, and used widely in agricultural to keep large areas pest and insect free.
Effective as a pesticide, chlorpyrifos is readily absorbed into the skin by touch, or from inhaling contaminated air. Tests in the past have found high levels of chlorpyrifos remain in the air up to 24-hours after delivery, while a 1996 study found that chlorpyrifos resulted in birth defects in humans, particularly affecting the heart, palate, brain, and nerves.
Dow Chemical’s concealed 294 reports of chlorpyrifos death
The dangers of chlorpyrifos did not become apparent until the mid-1990s. At the time it was found Dow were in possession of 249 reports of chlorpyrifos poisoning that they had failed to forward to the US Environmental Protection Agency (USEPA), despite being honor bound to do so.
Dow was subsequently fined US$732,000 for not submitting the reports, was ordered to remove the “safe” description from its chlorpyrifos product Dursban, and were ordered to pay an additional $2 million penalty.
In 2001 ahead of looming regulatory action by the USEPA, Dow in the US withdrew registration of chlorpyrifos for use in residences and places where children could be exposed, and also restricted its use on crops.
However, the agreement reached with the USEPA only applies to the US market and Dow still actively sells chlorpyrifos internationally, particularly in developing countries such as India, where it is labeled safe for humans and animals – a blatant lie by the company.
Chlorpyrifos: easily ingested by the body
Categorised as a neurotoxin, ingestion causes a disruption in the transmission of nerve impulses, resulting in dizziness, headaches, loose motions, increased urination, and salivation. When the ingestion is excessive, it could lead to paralysis, convulsions, and even death.
While quickly absorbed by the body, chlorpyrifos only has a half-life of one day, perhaps explaining why forensic doctors in Thailand, along with other international agencies, have not been able to detect it in tissue samples and postmortem examinations conducted on the seven dead tourists.
It would also lay to rest accusations of a cover up made by the family of New Zealand tourist Sarah Carter, who died after staying at the Downtown Inn in Chiang Mai, on a website they set up titled Thailand Travel Tragedies. It might also put to rest the incessant claims of one Bangkok-based freelance journalist who has been particularly vitriolic in condemning the handling of the deaths by Thai authorities and the abundance of conspiracy theories dreamed up by some sections of the Thailand expatriate community.
Although Dow remains the largest manufacturer of chlorpyrifos today, other manufacturers include Dow Agro Sciences LLC, a division of Dow Chemicals which also trades as Dow Elanco, Danish company Cheminova, Spanish company Makteshim-Agan, Garda in India, and US company Platte Chemical Company Chemical.
In an interview published in The Dominion, United Nations scientist, Ron McDowall, said there was a strong likelihood Wellington woman Sarah Carter and at least six other people had died from excessive exposure to chlorpyrifos, which causes identical symptoms to those suffered by guests staying at, or visiting the Downtown Inn in Chiang Mai.
Killed by an overzealous bed bug sprayer
According to Dr McDowall, the fact that traces of chlorpyrifos were found three months after Carter’s death and after the room was cleaned suggested there was a high concentration when she was staying there.
“I think she has been killed by an overzealous sprayer who’s been acting on the instructions of the hotel owner to deal with bed bugs”, Dr McDowall said.
Dr McDowall said he had consulted with other experts in New Zealand and Italy and all agreed the likely cause of death of the seven was from excessive exposure to pest control chemicals.
Thailand police confirmed they are looking into the possibility the tourists were killed by over exposure to pest control chemicals and had already raided the pest control company used by the hotel.
Richard Carter, father of dead tourist Sarah Carter, said it was “good to get an answer” about how his daughter died, adding that “it’s pretty horrific that they have such low standards that this can happen”.
If chlorpyrifos can be proved to be linked to the deaths of the seven tourists in Chiang Mai the result will be a serious blow to the city’s tourism industry, as well as to the general tourism sector in Thailand until authorities announce what steps they will take to prevent lethal chemicals such as this being used in tourist accommodation areas, how it will be policed, and whether any criminal charges are laid.
Chlorpyrifos may also explain the deaths of American tourist, Jill St Onge and Norwegian holiday-maker, Julie Michelle Bergheim, at The Laleena Guesthouse on Koh Phi Ph on May 6, 2009. Postmortem examinations, including one in Norway, failed to determine the cause of death of Ms Bergheim.
It was not possible to obtain comments from Chiang Mai government officials or management of Downtown Inn in Chiang Mai due to today being Sunday. A response from Dow Chemical had not been received up to the time of publication.
Feature photo AEC News Today
- Thailand authorities dismiss chlorpyrifos as cause of Chiang Mai hotel tourist deaths
- Chiang Mai tourist death hotel mystery remains, governor slams foreign media report
- Lost smiles in LOS as Thailand travel tragedies website goes live
He has spent extensive periods of time working in Africa and throughout Southeast Asia, with stints in the Middle East, the USA, and England.
He has covered major world events including Operation Desert Shield/ Storm, the 1991 pillage in Zaire, the 1994 Rwanda genocide, the 1999 East Timor independence unrest, the 2004 Asian tsunami, and the 2009, 2010, and 2014 Bangkok political protests.
In 1995 he was a Walkley Award finalist, the highest awards in Australian journalism, for his coverage of the 1995 Zaire (now Democratic Republic of Congo) Ebola outbreak.
Most recently he was the Thailand editor/ managing editor of AEC News Today . Prior to that he was the deputy editor and Thailand and Greater Mekong Sub-region editor for The Establishment Post, predecessor of Asean Today.
In the mid-80s and early 90s he owned JLF Promotions, the largest above and below the line marketing and PR firm servicing the high-technology industry in Australia. It was sold in 1995.
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In the US, “traces” of chlorpyrifos have been found in apples from New Zealand, the highest concentrations of all foods tested. What might this suggest?
Here is a bit of “news” that I haven’t seen reported anywhere:
Progress on epidemiologic investigation of myocarditis cases in Chiangmai (Updated 22 March 2011)
It might explain all the conspirator’s satisfaction with the “coincidence theory”.
Although one might suggest that the hospital has joined in the “cover up”, the report seems to contain some facts that none of the blogs or newspapers feel like reporting.
Thanks for reading Curt,
The document your refer to is one prepared by the Department of Disease Control, Ministry of Public Health, Chiang Mai and is referenced and linked to in my original article on the establishment of the Thailand Travel Tragedies website. It’s not an easy link for people to find – buried on a website that is predominately in Thai language.
Thank you for reading,
Why is your informative article illustrated by a photograph of a packet of a product containing methyl parathion?
Methyl parathion is a very different insecticide from chlorpyrifos as it is at least ten times more toxic than chlorpyrifos.
Thank you for reading.
The manufacturer lists this product under it’s range of “Chlorpyrifos Insecticides”.
“We offer a range of Chlorpyrifos Insecticides which includes Fenvalerate 0.4% D.P, Chlorpyrifos 50%, Cypermethrin, 5% E.C and Methyl Parathion 2% D.P.”
Thanks for reading,
Please note that it only takes one TEASPOON of chlorpyrifos taken orally to kill but it takes a ridiculous and unrealistic amount poured on the skin (4 ounces) or inhaled (a cloud of 15 grams breathed for 4 hours) to cause death. Chlorpyrifos is the most heavily used pesticide in the world so it is no surprise they found it in the hotel rooms because it is sprayed in tens of thousands of hotel rooms–but never with sudden deaths as these tourist experienced. The oral poison I believe they ingested doesn’t have to be chlorpyrifos, which apparently does have a smell—but, then again, if a teaspoon of it were put in a giant tropical drink or a spicy, garlic, onion dish—would you notice? At any rate, there are hundreds of pesticides many of them odorless and colorless and many if not most kill the same way: easily by ingestion, difficult by skin or lung. All other possible causes proposed so far–including chlorpyrifos acquired via skin or lung, toxic seaweed, fish, ‘regular’ food poisoning, pool, echovirus, Legionaires Disease–have been shown to be implausible. Let’s take note that Thailand cannot be the only country in the world without serial killers. Just because you don’t hear about them in the Thai media only means the Thais don’t do thorough investigations and, if they were to actually find one who was killing tourists, would be very likely to cover it up. To rule out a (serial) killer without a full investigation is a mistake no Western detective would make. I am ‘pushing’ the murder theory based on my knowledge of routine murder and mayhem in Thailand that never gets caught much less punished and also basing it on the symptoms of victims, which, at this point, ONLY match ingestion of insecticides. I am ‘pushing’ the murder theory so that this THEORY gets investigated, because no good investigator would rule it out unless the evidence were overwhelming to rule it out. There may be another viable possible cause put forth soon, but up until this date, the ONLY thing that ‘fits’ is INGESTION of pesticides.
insecticide? Probably. But not by breathing or skin
It is not surprising they found traces of Chlorpyrifos in the room. The stuff is the most widely used insecticide in the world. Chlorpyrifos may have been the culprit‚ÄìI‚Äôve said all along insecticides were at top of suspicion list‚ÄìBUT‚Ä¶Nope, can‚Äôt be from the sheets, the air or the walls. It takes 4 ounces (at least) on the skin of an adult to kill so the sheets would have had to have been soaked in the stuff. Soaked. And they would have had to have gotten the entire 4 ounces squeezed out of the sheets and onto just one body. Sorry, this ‚Äòsheet theory‚Äô doesn‚Äôt wash.
Plus there are very few‚Äìif any‚Äìcases of sudden deaths in the scientific literature resulting from dermal (skin) exposure.
‚ÄúChlorpyrifos is the world‚Äôs leading insecticide in volume terms(2). The acute oral LD50 (the Lethal Dose required to kill half of a population of laboratory test animals) for chlorpyrifos is between 135-165 mg/kg for rats(7). The dermal LD50 for chlorpyrifos in male and female rats is greater than 2,000 mg/kg. It is classified by the World Health Organisation as a Class II, ‚Äòmoderately hazardous‚Äô pesticide(8).‚Äù http://pmep.cce.cornell.edu/profiles‚Ä¶rifos-ext.html
So you can see that the dose needed to kill by dermal (skin) is 2,000 mg per kg body weight, which is equal to 2 grams per kg body weight. Chiang Mai victims weighed, let‚Äôs say, around 60 kg each, so to die from skin exposure they would have needed to have had 120 grams poured on them‚Äìabout four ounces.
But to die from oral exposure one only need 135 mg per kg or about 7 grams total to kill 50% of a any 60kg group exposed. A teaspoon of the stuff will weigh close to 7 grams so I would indeed like to see the fatuous governor or Chiang Mai, the idiot who has already said the 7 Chiang Mai deaths (see link below) are coincidences and who now says he will eat a ‚Äúspoon‚Äù of it‚ÄìI‚Äôd very much like to see him eat a teaspoon of chlorpyrifos while the cameras are rolling so we can determine if he is in the 50% that will live but get extremely sick, or in the group of 50% that will die. And if he uses a TABLEspoon instead of a teaspoon? His contortions and writhing and foaming at the mouth and respiratory arrest will make fantastic viewing on websites.
‚ÄúThe 4-hour inhalation LC50 (lethal concentration) for chlorpyrifos in rats is greater than 200 mg/m3. Three hundred and nineteen human exposure incidents were reported by the Pesticide Incident Monitoring System (PIMS) from 1970 through 1981, most resulting from inhalation and dermal exposure. Three human deaths were caused by chlorpyrifos‚Äù Chlorpyrifos
200mg/sq meter in a 5x5x3 hotel room would mean a 15 gram cloud of the stuff would have to be hanging around the room for four hours. So very doubtful the just suddenly dropped dead from breathing the stuff.
So you can see that out of the 319 exposures reported in 11 years in this one study, there were 3 deaths from the stuff even though most of the reported exposures were by inhalation and dermal exposure. (and the three deaths may have been from ingestion‚Äìstudy doesn‚Äôt say). There aren‚Äôt too many cases (or any) of sudden deaths from inhalation just as there aren‚Äôt many sudden deaths from dermal exposure because you need so much of the stuff to die by these routes. Many people made really sick by skin exposure and breathing? Sure. But not sudden deaths by skin or breathing it.
To reliably and quickly die from the stuff you have to eat only about a teaspoon of it. Not hard to slip a teaspoon of the stuff into an exotic drink or dish at a crowded market.
Plus, chlorpyrifos is sprayed all over the world in vast quantities and you never hear about people healthy one minute and dead the next who lay on some sheets or breathed some of it.
Plus, the Chiang Mai victims were staying in three or four different hotels, making it even more unlikely for skin exposure or breathing exposure.
Plus, I read‚Äìbut haven‚Äôt confirmed‚Äìthat chlorpyrifos really stinks and, if this is true, probably would have been noticed if in the air or on the sheets.(‚ÄúChlorpyrifos has a mild mercaptan (thiol) odor, similar to the smell of sulfur compounds found in rotten eggs, onions, garlic and skunks‚Äù)
The poison doesn‚Äôt have to be chlorpyrifos, which apparently does have a smell‚Äîbut, then again, if a little tiny teaspoon of it were put in a giant tropical drink or a spicy, garlic, onion dish‚Äîwould you notice? At any rate, there are hundreds of pesticides many of them odorless and colorless.
But drink a tiny amount of the stuff and you‚Äôre a ‚Äògonner‚Äô quickly.
Let‚Äôs all quit pretending that Thailand is the only country in the world without serial killers. Just because you don‚Äôt hear about them in the Thai media only means the Thais don‚Äôt do thorough investigations and, if they were to actually find one who was killing tourists, would be very likely to cover it up. To rule out a serial killer without a full investigation is a mistake no Western detective would make‚Äìunless the evidence was overwhelming.
John you say
“It would also lay to rest accusations of a cover up made by the family of New Zealand tourist Sarah Carter, who died after staying at The Downtown Inn in Chiang Mai, on a website they set up titled Thailand Travel Tragedies and at least one Bangkok-based freelance journalist who has been particularly vitriolic in condemning the handling of the deaths by Thai authorities, along with no shortage of wild conspiracy theories dreamed up by some sections of the Thailand expatriate community”
While this may be so there are a couple of interesting points to emerge. These conspiracy theories have germinated because the authorities up in Chiang Mai have either been unable or unwilling to satisfactorily get to the bottom of why these deaths occured. We all know there is a certain amount of corruption in the country and also a number of high profile crimes that have not been resolved over the years with the inference being that everything has not been above board. Added to that is apparent ease with which a probable solution has been found by people engaged by a small TV company from NZ.
Into this mix can be added an unscrupulous chemical company who will probably shrug their shoulders and say they can’t be held responsible for the incompetence of some pest control dimwit.
I’m afraid it all adds up to distasteful state of affairs. This is big news back home and one hopes it will not be allowed to fade away in Thailand.
Thanks for reading Michael,
The comment only refers to the difficulty in identifying the substance postmortem. The extremely short half-life would also explain why the autopsy performed in Norway after one of the Koh Phi Phi deaths was unable to determine a cause of death. A cover-up would imply Thai authorities new the cause of death and were concealing it, much like the actions of Dow in the 90s.
Now that the cause is known the actions of foreign governments and travel industry bodies, along with that of the Thai government, are all on the table and subject to judgement.
Comments have been sought from all interested parties. Please check back again soon.
John Le Fevre