T-2 mycotoxin
From Wikipedia, the free encyclopedia
T-2 (also known as "Yellow Rain"), a trichothecene mycotoxin, is a naturally-occurring mold byproduct of fusarium fungus which is toxic to humans and animals. It is the only mycotoxin known to have been used as a biological weapon, but ingestion may come from moldy whole grains.
The clinical condition it causes is alimentary toxic aleukia and a host of symptoms on organs as diverse as the skin, airway, and stomach.
T-2 was discovered as a weapon by Russian scientists after a spring harvest delayed by World War II produced flour contaminated with fusarium and distributed in bread. Many were sickened, some fatally. T-2 has also been suggested as a cause of the 430 AD plague in Athens. T-2 is an infrequent contaminant in animal feed.
T-2 has been suggested as a cause of Gulf War Syndrome for some United States troops exposed to a mortar shell shot by Iraqi forces during the Persian Gulf War; and as the substance used to poison Viktor Yushchenko during his 2004 presidential election campaign (though doctors now believe it was dioxin).
[edit] Yellow rain incident
The name yellow rain derives from incidents in Laos and Vietnam beginning in 1975, when the two communist governments, allied with the Soviet Union, retaliated against Hmong people tribes which had sided with the United States during the Vietnam War. Refugees fled from what they described as chemical warfare attacks by low-flying aircraft; most of the reports were of a yellow, oily liquid that the Hmong dubbed "yellow rain". Those exposed suffered neurological and physical symptoms including seizures, blindness, and bleeding. Similar reports came from the Vietnamese invasion of Cambodia in 1978.
In 1981, after noting etiological similarities, U.S. chemical weapons experts matched samples taken from an alleged attack in Laos to trichothecene signatures, and hypothesized that T-2 was discovered accidentally through contamination and later weaponized. Secretary of State Alexander Haig announced in September 1981 that
- For some time now, the international community has been alarmed by continuing reports that the Soviet Union and its allies have been using lethal chemical weapons in Laos, Kampuchea, and Afghanistan. . . . We have now found physical evidence from Southeast Asia which has been analyzed and found to contain abnormally high levels of three potent mycotoxins--poisonous substances not indigenous to the region and which are highly toxic to man and animals. [1]
In 1983, a now-declassified CIA report summarized the history of T-2 development in the Soviet Union, where it was referred to as lebeda, Russian for millet or animal feed, and weaponized for aerial delivery.
In 1987, these charges were later disputed by Harvard biologist and biological weapons opponent Matthew Meselson, who travelled to Laos and conducted his own investigation. Meselson's team noted that trichothecene mycotoxins occur naturally in the region and questioned the witness testimony, suggesting an alternate hypothesis that the yellow rain was the harmless fecal matter of honeybees. The Meselson team offered the following as evidence: separate "yellow rain drops" which occurred on the same leaf, and were accepted as authentic, consisted largely of pollen; each drop contained a different mix of pollen grains, as one would expect if they came from different bees, and the grains showed properties characteristic of pollen processed by bees. The different composition is striking, as it implies that the Soviets would have had to have very sophisticated mixing apparatus. In addition, many of the "native people" who made claims that they were attacked by chemical weapons could reasonably be seen as partial to the US. As of 2005, the question has not been fully resolved.
