Deadly mycotoxins were blamed as the source of Southeast mycotoxins Asia “Yellow Rain” are a large by CIA–30 years family of chemically-related later and we still mycotoxins produced by various do not know the truth involved species of fungi, most notably Britt A. Bunyard an oily yellow species but also species liquid that made a sound like nyone cognizant of world news rain when it struck leaves or roofs, of Stachybotrys, Trichoderma, in the early 1980s, will remember causing the Hmong to call it “Yellow and Trichothecium. A poisonous the conflict in Southeast Asia. Rain.” Eyewitnesses claimed that Yellow mushroom in Japan and , This period of the War was well A Rain smelled like gunpowder and left a after the USA was defeated and sent back Podostroma cornu-damae, residue of sticky yellow spots on leaves, home (in a similar fashion to previous produces six trichothecenes: rocks, and rooftops. Exposure to high colonial powers there: Great Britain, satratoxin H, roridin E, doses reportedly caused heavy bleeding France, etc.). Communism spread through from the nose and gums, blindness, verrucarin and others (see FUNGI the region like mycelia across a Petri plate, tremors, seizures, other neurological vol. 4, no. 5). Trichothecene as predicted (remember the “Domino symptoms, and death. Similar incidents mycotoxin poisonings are Theory”?). After victory in South were reported in Democratic Kampuchea Vietnam, a unified Communist Vietnam mostly food borne and can be () in 1978 after the Vietnamese was attacked by the paranoid Communist very dangerous to humans and take-over there. The victims, both of Cambodia. (The Khmer other animals. They are most injured and killed, were reported to be in Rouge, led by “Brother Number One” the thousands. Chemical and biological commonly found in spoiled or Pol Pot, were actually backed by the USA weapons were suspected. molded grain like wheat, oats, early on, until they realized the Khmer The wave of conservatism that Rouge leaders were totally insane.) The barley, or maize (corn). The would later sweep Ronald Reagan into Khmer Rouge fell to the Vietnamese; most common fungi suspected office was turning up the rhetoric that those still in Cambodia who had sided are Fusarium graminearum (the the was violating arms with the USA had to go into hiding to control treaties. And in particular, asexual form of Gibberella zeae), avoid persecution. Communism also took violations of treaties that banned the F. sporotrichioides, F. poae and hold in ; ethnic , who use of chemical and biological weapons. F. equiseti. In North America, had fought on the side of the USA during Many newspaper editorials, namely the war, fled to the hills, the jungle, and livestock are affected annually; , led the charge. the Thai border to escape persecution by globally, humans occasionally A November 1981 editorial in WSJ the Lao communists (Pathet Lao). During are afflicted from trichothecene- condemned: “Except to the willingly the summer of 1975, reports began obtuse, the evidence is conclusive. The contaminated food. The most trickling out of Laos that government Soviets have long been engaged in the famous case involving humans forces were using Soviet-supplied development and production of chemical chemical weapons to terrorize the Hmong occurred shortly after World and biological weapons. They have and drive them from their mountain War II in the Soviet Union, and used these weapons in Yemen in the sanctuaries. Refugees described a variety it is believed 100,000 people 1960s, and now in Cambodia, Laos, and of toxic agents delivered by low-flying may have been killed by grain Afghanistan.” The WSJ in this and future aircraft; about 70 percent of the reports contaminated with T-2 toxin. editorials kept up the pressure, even criticizing skeptics for giving the Soviets Since the Yellow Rain was “the benefit of every conceivable doubt.” now clearly a chemical Making a case for biowarfare: weapon, who was making it? Obviously not the Vietnamese, the mycotoxins they were unable to make Initially, experts in the conventional weapons the USA were mystified by the alleged they were using. It had to be a attacks in Southeast Asia because the Communist ally, and one with the symptoms described by refugees did sophistication to build chemical not match the effects of any known and biological weapons. China chemical or biological agents. In July was ruled out as they were not on 1981, however, US Army toxicologist friendly terms with the Vietnamese Dr. Sharon Watson noted a striking (to say the least). That left the Soviet similarity between the reported Union. On September 13, 1981, symptoms and those resulting from based on the preliminary findings of exposure to fungal poisons called the US scientists, then-US Secretary trichothecene mycotoxins (poisonous of State , accused the compounds made by molds that infest Soviet Union of supplying trichothecene grain, see box). Samples of Yellow mycotoxins to its Vietnamese and Rain from an alleged attack site in Laotian allies to use as a weapon against Laos were secretly collected by the Hmong villagers who had sided with the CIA and analyzed by a laboratory at during the the University of Minnesota. Three and against anti-Vietnamese forces in different trichothecenes were detected Cambodia. Secretary Haig charged in concentrations and mixtures not publically, “For some time now, the known to occur in . Another piece international community has been of circumstantial evidence was the fact alarmed by continuing reports that that consumption of trichothecene- the Soviet Union and its allies contaminated grain had long been a have been using lethal chemical serious public health problem in the weapons in Laos, Kampuchea Soviet Union, leading to intensive [Cambodia], and Afghanistan. research on mycotoxin poisoning. The We have now found physical US intelligence community speculated evidence from Southeast Asia, that this research had caused the Soviets which has been analyzed and to recognize the military potential of found to contain abnormally high levels one trichothecenes and to develop them as of three potent mycotoxins—poisonous which a weapon. (We do know that the Soviet substances not indigenous to the region could shed light Union had a large-scale chemical and and which are highly toxic to man and on what happened, has been biological weapons research program, as animals.” The Reagan administration long-sought through the Freedom of did the USA. Since the end of the Cold continued its charges against the Soviet Information Act. All requests were War a number of documentary Union throughout the early 80s as recently denied. films have made on the evidence mounted. Newspaper editorials Independent scientists topic.) called for the Soviets to be reined in; books on the topic flew off bookstore determine otherwise shelves (Evans, 1983). Even without this critical piece of I hadn’t thought about this episode potentially damning evidence, it was in American history for a long time. A long ago pretty well established that the February 11, 2012, editorial published Yellow Rain was not an act of biowarfare. in brought it Over the years, skeptics — led by all back, asserting “that flawed or Harvard University scientist Dr. Matthew distorted intelligence led the Reagan Meselson — have persuasively disputed administration to accuse the Soviet most of the claims and accusations Union and Vietnam of using leveled at the Soviet Union and Vietnam. chemical weapons, known as Meselson should be a name recognized yellow rain.” Why did The Times by all biology students. He is a legendary bring this up? And why now? It American geneticist and molecular seems that a classified critique biologist who originally studied under of the intelligence behind the great Linus Pauling. Later, his those charges, written many research (along with colleague Franklin years ago for the CIA, and Stahl in the 1950s) was important Winter 2012 • Volume 5:5 • FUNGI 7 The scientific critics also raised doubts occurred on the same leaf, and which about the reliability of the refugee were accepted as authentic, consisted testimony, concluding instead that the largely of pollen; each drop contained alleged victims had confused chemical a different mix of pollen grains, as one attacks—where poisons rained down would expect if they came from different from the sky—with harmless showers bees, and the grains showed properties of yellow feces released by swarms of characteristic of pollen processed by giant Asian honeybees. The independent bees (the protein inside the pollen was scientific data was completely dismissed gone, while the outer indigestible shell by the Reagan administration. They remained). Further, the pollen came from used the usual tactic by those without plant species typical of the area where scientific facts to stand on: they labeled the drop was collected. The different Meselson as a long-time lefty who was composition was striking, as it implied unpatriotic and wanting to undermine that the Soviets would have had to have the US government. Indeed, Meselson, very sophisticated mixing apparatus that Fusarium growing on corn kernels for a while was the butt of late night jokes could take pollen from local Southeast in culture (above) and on cut tree by pundits and talk shows. Yellow Rain … Asian plants, treat it as done by bees, stump (below), courtesy of G. bee poo? Yes, they asserted; the yellowish and then mix the pollen into different Barron. drops found on foliage were most likely drops, such that different drops contain produced by honeybees, which often different pollens. in showing how DNA replicates, leave their nests en masse and produce And what about the testimonies recombines, and is repaired in cells. The showers of pollen-laced feces that can of scores of Hmong refugees; claims two used a DNA-DNA hybridization cover an acre or more with hundreds of skin lesions, burns, gastric upset, experiment where the double- of thousands of yellow spots. They diarrhea, and flu-like symptoms? Pretty stranded DNA was “unzipped” and suspected (but could not prove) that the much all these testimonies usually fell when the double-stranded condition traces of poison found in some samples apart in follow-up interviews. Of the was returned, it was found that the were false positives caused by laboratory few documented cases of illness, the replication of DNA proceeded in a semi- contamination. Additional, independent illnesses were repeatedly shown to conservative fashion. That is, one of the laboratories in the United States, Britain, be due to natural causes. Many of the two strands is used as a template for the France and Sweden analyzed scores testimonies were based on responses second strand. Until their discoveries, of samples and never found a trace of by “victims” who did not actually scientists argued over many possible poison. (It should be noted that the understand the questions asked them by ways DNA was replicated. Minnesota lab where the original CIA the interviewers. Many experts felt the Skeptical of the CIA’s claims of samples were sent, is a mycotoxin testing mass hysteria surrounding the Yellow biowarfare, Meselson led a team of facility and handles tons—literally—of Rain seemed part of uncontrolled rumors researchers into the jungles of Southeast grain and other agricultural commodities that spread throughout the land. This Asia to investigate Yellow Rain. The laden with mycotoxins.) is not hard to believe; US sympathizers skeptics argued that trichothecene Furthermore, the Meselson team really were driven from their homes, mycotoxins do occur naturally in offered the following as more specific persecuted and even killed (and the Southeast Asia; indeed, the tropical (and more damning) evidence from persecution continues to this day in some jungles of Southeast Asia are teeming the thousands of samples collected: regions). Likewise, the “victims” sided with molds and fungi of all sorts. separate “yellow rain drops” which with the USA and no doubt would have believed their allegations might benefit them later. No chemical munitions have ever been found, and none of the hundreds of Vietnamese soldiers who were debriefed provided a shred of information that suggested the use of a weapon remotely resembling Yellow Rain. I remember this period well. A number of agencies and even pro-military magazines offered huge rewards to any Vietnamese pilot who defected with Soviet chemical warfare apparatus on his jet (including, famously, $100,000 offered by Soldier of Fortune magazine). Recent “Yellow Rain” episodes Back in the 80s, when I first heard

8 FUNGI • Volume 5:5 • Winter 2012 the claims that what was obviously war in Iraq (based almost entirely on Tucker, J.B. 2001. The “Yellow Rain” (to me and most others) a chemical claims of weapons of mass destruction controversy: Lessons for weapons attack, in reality, was a natural by a single informant code named, compliance. Nonproliferation Review phenomenon (a mass flight of defecating curiously, “Screwball”). Two separate bees), I have to admit that it sounded bipartisan commissions have weighed in implausible. I likely laughed right along and found there was no actual evidence with the late night comedians. This was for weapons of mass destruction in because I’d neither seen nor heard of Iraq. And who could forget the famous such a phenomenon before. Nowadays, I 2001 Anthrax attacks and equally have friends who tend bees and entirely famous botched investigation? (It seems all of them have conferred that, oh yes, unlikely that anyone other than the the phenomenon is well known in the single suspect under investigation could bee community, but when it occurs in have done it, but we will never know, North America it’s on a much smaller as he committed suicide.) Incidentally, scale. And usually in agricultural areas there is a recently-published book far from any witnesses. on the Anthrax attacks investigation The scientific critics’ view of Yellow (see below) by Jeanne Guillemin, an Rain-is-bee-poo has been receiving expert on chemical and biological additional support from nature recently, weapons. (She is also the wife of the from parts of Asia as disparate as aforementioned .) and Japan. In June 2002, a yellow-green Although we may never know what rain fell from the sky on the town of happened in the Anthrax attacks, it Sangrampur, near Calcutta, India. seems that the mystery surrounding the Rumors spread that the rain might be Yellow Rain attacks could be resolved if contaminated with toxins or chemical all known documents and evidence were warfare agents. Shortly after the “attack,” made public. The classified report that however, Deepak Chakraborty, chief Dr. Meselson is seeking was done by a pollution scientist for the Indian state of former covert operative and contract West Bengal, reported that the yellow- historian, and examined how the green droplets were in fact bee feces intelligence community came up with its containing pollen from local mangoes finding that Yellow Rain was a chemical and coconuts. He concluded that the weapon. The CIA is, of course, “claiming colored rain may have been caused by that releasing the report would reveal the migration of a giant swarm of Asian sensitive information about intelligence honeybees, which are known to produce sources and methods, as well as the “golden showers” (see Pearce, 2002). organization and function of the CIA.” The risks of failed The Times editor suggested otherwise: “Thirty years later, that is preposterous. A “intelligence” better guess is that the agency is worried Fusarium conidia, courtesy of Despite the best efforts of those in about being embarrassed by what the G. Barron. the “intelligence community” (to use report says about how the intelligence the parlance of late), sometimes our community did its work” (The New York political leaders make hasty decisions Times, editorial, February 11, 2012). or crime investigations get botched. The Further Reading mysterious Yellow Rain episode is just one example. Another was a misguided Evans, G. 1983. The Yellow Rainmakers: Are Chemical Weapons Being Used in Southeast Asia? Verso Editions, London; “…intelligence analysis ISBN: 0860910687. is an uncertain game, all Guillemin, J. 2011. American Anthrax: too vulnerable to error Fear, Crime, and the Investigation of and politically-motivated the Nation’s Deadliest Bioterror Attack. Times Books, New York, 336 pp. distortion. That experience Pearce, F. 2002. Green rain over India has done little to change the evokes memories of paranoia. intelligence community’s New Scientist 174: 13. passion for secrets, whether The New York Times. 2011. Editorial: or not they need to be kept.” Still secret after 30 years? http://www. The New York Times, editorial, nytimes.com/2012/02/12/opinion/ sunday/still-secret-after-30-years.html February 11, 2012 Winter 2012 • Volume 5:5 • FUNGI 9