Sunday, November 07, 2004

Discovering the Obvious

It appears that Gulf War Syndrome is caused by sarin exposure, according to a BBC report.

A Senate investigation heard in 1994 that each of the 14,000 chemical weapons alarms around the troops went off on average twice or three times a day during allied aerial bombardment of Iraq - a total of between one and two million alarms. All were said to have been false alarms.

Nice, eh? These sensors, which were intended to protect troops, had as many 42,000 false positives per day, and about 1,500,000 false positives in total. And what did these "false alarms" prove, before now? Why, that none of these soldiers could've been exposed to sarin!

You better believe there's more:
Another source of exposure could have been for the thousands of troops stationed near Khamisiyah in southern Iraq in March 1991. After the fighting was over, a large chemical weapons dump was blown up, creating a plume of gas, which would have contained sarin and which could have affected at least 100,000 allied soldiers, possibly far more, the New Scientist said.
That sounds about right. One funny thing about sarin is, it's easily volatilized into an aerosol by explosions. Another funny thing is, it's heavier than air, so it tends to drift back down to earth pretty quickly.

The article goes on to express mild surprise that low-level sarin exposure could have long-term health consequences:
British and US authorities have always denied that any troops were affected by nerve gas, as no soldiers showed the classic symptoms of acute exposure. But the New Scientist said: "It now appears that very small, repeated exposure can also harm."
Despite the attempt to treat this as a new finding, it's been well known for decades that low-level exposures to sarin are potentially dangerous. Like many widely used pesticides, sarin is an organophosphate, a type of compound that specifically targets the central nervous system by disrupting neurotransmitters; that's why it's called a "nerve agent."

Organophosphates are very heavily regulated in the United States, where we use about 80 million pounds per year. They've been thoroughly tested for use in industry, and they're known to have serious short- and long-term effects. The US EPA says:
They cause known effects – quick (acute) and longer term (chronic) – to humans as well as to wildlife.
That being the case, there are strict guidelines for allowable amounts of organophosphates in food and water, and for on-the-job exposures, and they're very low. Not as low as they probably should be, mind you...but low enough that a massive vapor plume of sarin - one of the most toxic organophosphates known - would be orders of magnitude higher than the allowable level.

While the CDC claims that nerve agents don't have the long-term neurological effects of other organophosphates, there are no good data to support that claim, and to my knowledge there hasn't even been a plausible scientific explanation offered as to why an organophosphate like sarin would have fewer chronic effects than closely related commercial pesticides. On top of which, there are animal and human data which strongly suggest that some sensorimotor effects of sarin exposure are persistent.

Some scientists call these results inconclusive, and maybe they're right. If so, it sounds to me like grounds for taking extreme precautions. When you're talking about one of the deadliest substances on earth, "inconclusive" should mean "don't take stupid chances."

Anyway, I'm bringing this up mainly because it's such a perfect example of how the well-known hazards of certain chemical compounds can suddenly be "newly discovered," in order to excuse whatever flawed or corrupt policies led to a pattern of dangerous exposures.

1 comment:

Anonymous said...

good call, thanks.