Arsine is an unpleasant gas and I had a big cylinder full of it. We used it in gas deposition chambers to dope semi-conductor surfaces in our microelectronics lab in Queens. The main route of exposure is via inhalation
although poisoning through the skin has been documented. This gas attacks the haemoglobin in the red
blood cells causing them to be destroyed by the body.
Most people are
more familiar with hydrogen cyanide as a means of killing. Hydrogen cyanide irritates the eyes and the
respiratory tract. There is a faint
smell of almonds that around 50% of the population will be able to detect. In forensics, both gases will leave the
victims with particularly red blood, a usual indicator that some sort of
poisoning has occurred. Unfortunately,
with Arsine you will be dead long before you smell it. There may be a slight smell of garlic on the
breath of a victim of arsine poisoning and for cyanide poisoning that sweet
almond smell can sometimes be detected.
It is particularly scary that Arsine does not smell, you know your nose
will not alarm you to its presence.
I
reckon arsine even looks ugly, but that could be my paranoia. This flammable
gas, ignites spontaneously in air, and as well as being highly toxic is
one of the simplest compounds of arsenic. Here is a picture of a molecule
of the stuff. Perhaps, you are more
familiar with its other form arsenic?
Years ago they used the Marsh test to determine if arsenic had been used
on a corpse. This test produces arsine
as an intermediate product. Despite its lethality, it finds some applications
in the semiconductor industry. Which is
why, when I worked in university in N. Ireland, I had a huge canister of the
stuff in the access corridor of our laboratory.
Not a small tiny campsite gas cylinder a huge one a meter and a half
high.
Remember that exposure to arsine
concentrations of 250 ppm is rapidly fatal: concentrations of
25–30 ppm are fatal for 30 minute exposure, and concentrations of
10 ppm can be fatal at longer exposure times. That is 10 parts per million, not an awful
lot of the stuff is needed to take you down, silently without a smell not even
a sniff of warning. So, to have a huge
tank of the stuff sitting in plain view was giving the fireman heart
palpitations. He had come to do the
yearly fire inspection of the building and had reached the tenth floor without
any major complaint. Finding a corridor
full of some of the most toxic gases, on this the last floor, was like a
nightmare. Part of their job is knowing
when they are called to a building, in the event of a fire etc, exactly what the
major dangers are. Being aware that here in
a quiet innocent corridor such dangers lurked was very important. I felt sorry for him filling in all his
papers. For firemen it must seem the
rest of the world is just trying to be difficult, lighting fires in forests,
putting oil on stoves and forgetting, or buying in huge quantities of extremely
toxic gas.
He was a reasonable man in an
unreasonable world. I sympathised, he
shrugged his shoulders and said not to worry.
They had just done a safety analysis on a Monsanto factory in N. Ireland
and had found there, the biggest store of mustard gas in Western Europe. That is the stuff used during the world war I. Mind you that it turns out is the tip of a very
unpleasant iceberg. Among the many
achievements of this company Monsanto has:
1. Produced rBGH, also known as
Bovine Somatotropin. It is a synthetic hormone that is injected into cows in
order to increase milk production. However, many studies have shown that this
produces adverse effects, behaving as a cancer accelerator in adults and
non-infants. This biologically active hormone is associated with breast cancer,
colon cancer, lung cancer and prostate cancer.
2. Other major products have included the herbicides 2,4,5-T, and DDT. The excitotoxin aspartame, and the controversial PCBs were also developed and produced by Monsanto. The company was sued, for the side effects of its Agent Orange defoliant used by the US military in the during the Vietnam War. More than 21,000,000 US gallons (79,000,000 L) of Agent Orange were sprayed across South Vietnam. According to the post-war Vietnamese government official statistics, 4.8 million Vietnamese were exposed to Agent Orange, resulting in 400,000 deaths and disabilities, and 500,000 children born with some form of birth defect. Furthermore, internal documents from the companies that manufactured it reveal that at the time Agent Orange was sold to the U.S. government for use in Vietnam, it was known that it contained a dioxin.
3.
Its most recent pesticide
Round-up is thought to be worse than DDT. Monsanto is the world’s largest producer of
the herbicide “Glyphosate”, commonly used in “Round-Up”. (Glyphosate is the
most used herbicide in the USA, and Roundup is the number one selling herbicide
worldwide since at least 1980.) Roundup is also at the heart of much
controversy in the scientific and health community, concerning human and
mammalian side effects. A 2008 scientific study has shown that Roundup
formulations and metabolic products cause the death of human embryonic,
placental, and umbilical cells in vitro, even at extremely low
concentrations.
I remember being reassured, all the years ago,
that whatever horrors we had in our university Microelectronics Lab at least we were not
the worst offenders. Several decades later
I am no longer reassured and am wondering what these guys are doing to us and our
environment. I won’t call it the most
evil company on earth but some do. Mind
you be warned this article is a bit over the top!
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just love your one word comments xx
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