Re: Chiang Mai: Unexplained myocarditis - 7 deaths - chlorpyrifos insecticide poisoning suspected
Re: Chiang Mai: Unexplained myocarditis - 7 deaths - chlorpyrifos insecticide poisoning suspected
http://www.promedmail.org/pls/apex/..._BACK_PAGE,F2400_P1001_PUB_MAIL_ID:1000,88412
Archive Number 20110512.1459
Published Date 12-MAY-2011
Subject PRO> Undiagnosed deaths - Thailand (07): (CM)
UNDIAGNOSED DEATHS - THAILAND (07): (CHIANG MAI)
************************************************
A ProMED-mail post
<http://www.promedmail.org>
ProMED-mail is a program of the
International Society for Infectious Diseases
<http://www.isid.org>
Date: 10 May 2011
Source: Yahoo UK News [edited]
<http://uk.news.yahoo.com/british-couple--killed-by-bed-bug-spray--on-holiday.html>
The deaths of 7 tourists -- including an elderly British couple --
have been connected to a toxic bed bug pesticide found in the Thailand
hotel they all visited.
A male pensioner, 78, and his wife, 73, were found dead in their room
at Chiang Mai's Downtown Inn while in the northern tourist resort of
Chiang Mai on 19 Feb 2011.
Their deaths are the latest in a string of fatalities that occurred
during the months of January to March 2011, including that of a
23-year-old female New Zealander less than 2 weeks ago.
According to Thai authorities, the elderly couple suffered fatal
heart attacks within minutes of each other, though family members say
the couple had no history of heart problems.
The female New Zealander became seriously ill on 3 Feb 2011 while
staying at the hotel. She was taken to a local hospital but died from
heart inflammation one day later.
The condition of her 2 travelling companions who were sharing her
room also deteriorated, and one survived only after emergency heart
surgery.
Thai officials were quick to attribute the deaths to "toxic seaweed"
that was being sold at a nearby bazaar, but the persistent campaigning
of the female New Zealander's father over what he alleges is a "cover
up" has sparked extensive probes from the media.
An investigation aired by New Zealand's 60 Minutes program found
small traces of the insecticide Chlorpyrifos -- used to kill bed bugs
-- in the hotel room where the female New Zealander was staying.
Reporters for the program posed as hotel guests and took swabs from
the 5th floor room, which then underwent tests.
United Nations toxicologist Ron McDowall, who carried out tests on
behalf of the channel TV3, said the symptoms the young woman and the
other tourists had had suggested they had died from an over-exposure
to the toxic chemical.
Dr McDowall got 2nd and 3rd opinions from experts in New Zealand and
Italy who supported his belief.
"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 told 60 Minutes.
The fact that Chlorpyrifos was found 3 months after the young woman's
death, and after the room was cleaned, suggests there was a high
concentration of the toxin present while she was staying there, he
said. He added that tests done on her body were useless due to the
difficult nature of identifying poison from blood samples.
"The chemical is absorbed by the body very quickly. It only has a
half-life of a day, so it can be very hard to predict the event."
The female New Zealander's father said TV3 had presented a strong
case that Chlorpyrifos had caused his daughter's death.
"I think they've proven that they really don't have an interest in
resolving the issue, calling it a coincidence for a start, and also to
have systematically gone around and covered up as much of the evidence
as they possibly could when they had wind that TV3 were about to do an
investigation," he said.
A female Thai tourist guide was also found dead in the hotel the day
before the young woman became sick, and another Canadian man who died
did not stay in the hotel but is understood to have visited.
Thai police have raided the company in charge of eradicating insects
at the Downtown Inn, and Chiang Mai's Head of Public Health suspects
the pest controllers could have made a mistake.
"It's possible that they mixed together the wrong chemicals," Dr
Surasing Visaruthrat said.
The governor of Chiang Mai, ML Panadda, claimed the tourists' deaths
were just bad luck: "I do believe coincidence ... it is a very bad
occasion and such bad luck for that hotel."
The Downtown Inn continues to operate, offering rooms from GBP 25
[USD 41] a night.
--
Communicated by:
Spencer Whibley
Poland
<spencer@whibley.org>
[The presence of residues of Chlorpyrifos this long after the cases
visited the hotel is easily explained. Many establishments use some
form of pesticide on a regular basis, as probably did this one.
Therefore, the residues found are not necessarily remaining from when
the cases were in the room.
Chlorpyrifos is an insecticide that is a white crystal-like solid
with a strong odor. In other words, the residents of the hotel room
would be able to smell this chemical if it were mixed incorrectly, in
a stronger than appropriate fashion, or if it were used undiluted. It
does not mix well with water, so it is usually mixed with oily liquids
before it is applied to crops or animals. However, there are water
soluble powders available, but they leave a light residue that may
resemble spilled powder.
Chlorpyrifos is not well absorbed by the skin. Undiluted hot or
molten product may be absorbed through the skin. However, we have had
no reports of burns on the body, and this molten type of product would
likely produce a burn. Excessive Chlorpyrifos (of normal, not molten
product) on the skin should be removed by thorough washing. Some of
these people have survived, but I do not recall any report of them
smelling the chemical or needing to wash it off.
It may be absorbed from the gastrointestinal system. Large doses are
generally required to produce death, so a question arises about any
food eaten in the hotel that may represent a source of contamination
for ingestion.
Excessive exposure (by any route) may produce organophosphate type
cholinesterase inhibition. Signs and symptoms of excess exposure to
Chlopyrifos may be headache, dizziness, un-coordination, muscle
twitching, tremors, nausea, abdominal cramps, diarrhea, sweating,
pinpoint pupils, blurred vision, salivation, tearing, tightness in the
chest, excessive urination and convulsions.
Prolonged inhalation of high concentrations would have been
immediately offensive to the sense of smell. Even at normal
concentrations, this product has a recognizable odor that most people
can smell.
While one of the clinical signs of intoxication is a tightness in the
chest, this is not necessarily a heart attack or another heart issue.
It may be, but it may not be. Just because the cases experienced some
heart problems does not make a convincing case for Chlorpyrifos.
At the moment, I would suggest that a residue is easily explainable,
and heart problems are not convincing enough to pin it on the
chemical. I think further forensics and investigation are in order. -
Mod.TG]