Toxins yellow rain

Diagnosis Be suspicious if an aerosol attack occurs in the form of yellow rain with droplets of yellow fluid contaminating clothing and the environment. Confirmation requires testing of blood, tissue and environmental samples. As for treatment, there is no specific antidote however, super-activated charcoal should be given orally if the toxin is swallowed. The only defense is to wear a protective mask and clothing during an attack. No specific immunotherapy or chemotherapy is available for use in the field. 

In early studies, the LD50 values for DAS and T-2 toxin administered i.v. in swine were determined to be 0.37 and 1.3 mg/kg, respectively (Weaver et al., 1978a, b). Acute effects included vomiting, lethargy, frequent defecation, and posterior paralysis. Following the yellow rain ... 

It is reported that T-2 toxin has been used in biological warfare in Kampuchea, Laos and Afghanistan, by the Russian army under the name of Yellow Rain. 

Nivalenol. Powerful toxin derived from Fusar-ium nivale. Haemorrhagic, vesicant, necrosis producing, nausea, vomiting. Suspected constituent of yellow rain deposits during conflict in South-East Asia, although deposits also said to contain bee excreta. 

Mycotoxins in biological and environmental samples may be identified by gas chromatography technique. The method however, is not sensitive. Exposure to the toxin may be diagnosed from the symptoms in the victims and, as well assessed from observation of any yellow rain. 

The trichothecene mycotoxins, which are toxins produced by various species of fungi, are also examples of low-molecular-weight toxins (MW < 1,000 d). The yellow rain incidents in Southeast Asia in the early 1980s are believed to have demonstrated the utility of one of the trichothecene mycotoxins, T-2, as a biological warfare agent. 

When delivered at low doses, trichothecene mycotoxins cause skin, eye, and gastrointestinal problems. In nanogram amounts,4,25 they (T-2 toxin, in particular) cause severe skin irritation (erythema, edema, and necrosis).4,6 Skin vesication has been observed in a number of humans exposed to yellow rain attacks.4,14,15 T-2 toxin is about 400-fold more potent (50 ng vs 20 pg) than mustard in producing skin injury.26 Lower-microgram quantities of trichothecene mycotoxins cause severe eye irritation, corneal damage, and impaired vision.4 16 26 27 Emesis and diarrhea have been observed at amounts that are one fifth to one tenth the lethal doses of trichothecene mycotoxins.26... 

In areas that have experienced a yellow rain attack, environmental assays have been in the range of 1 to 150 parts per million (ppm) and blood samples in the range of 1 to 296 parts per billion (ppb).8"1016 22 In the laboratory, at 10 and 50 minutes after an intramuscular exposure to 0.4 mg/kg of T-2 toxin in the dog, plasma concentrations of T-2 toxin were 150 and 25 ppb, and for HT-2 toxin were 50 and 75 ppb, respectively.60 Thus, any screening procedure for trichothecene mycotoxins in biomedical samples must have detection limits of 1 to 100 ppb. Most of the analytical procedures require extraction and cleanup treatment to remove interfering substances.73... 

Yellow rain British analyses find no toxin. Nature. 1986 321 (6069) 459. News. 

Toxins produced by fungi, i.e., mycotoxins, are considered possible BW agent candidates and have been controversial for decades, including the putative agent in Yellow Rain. Trichothecene (T2) toxin is among the most poisonous of the known mycotoxins. Because the Fusarium toxin s effects in animals... 

The notion that the people of Laos and Cambodia were attacked by their Vietnamese neighbours by means of a chemical toxin sprayed from aircraft had become a bit of a joke even before Dr Matthew Meselson turned it into pastiche [sic] by remarking that most of what appears to be yellow rain consists of the excrement of bees. ... 

By 1986 Meselson s attitude had hardened. He had found earlier reports of yellow rain, from Cambodia in 1965 and China in 1977. In the latter case, the substance had been found to be bee faeces. He now took the view that the evidence for the US Government s allegation of toxin warfare has collapsed .Meselson dismissed the positive findings of Mirocha and Rosen on the grounds that no other laboratory had been able to repeat them, and that neither laboratory presented adequate controls - a statement strongly disputed by the... 

The need for detoxification of commodities contaminated by trichothecene mycotoxins has been known to be of significance by Bamburg et al. (1971). The yellow rain controversy (Mirocha, 1983) has made the interest in trimethecenes world-wide. Stahr, et al. (1985) has shown that T-2 toxin and diacetoxyscirpenol can be volatilized and trapped for analysis. Thermally removing the toxins from commodities was attempted in this work. 

The toxin became known as yellow rain due to its characteristic appearance as a yellow-coloured smoke or dust, which formed sticky droplets when sprayed. Due to its stable nature, deliberate release of T-2 toxin could utilise surface or aerial spraying of the toxin, or dispersal in bombs, mortars or rockets. It is odourless and tasteless. In a deliberate attack respiratory features are likely to predominate. 

MYCOTOXIN. A toxin produced by fungi. Such toxins include the trichothecenes implicated in the yellow rain episode and aflatoxin. 

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