Analysis for trichothecenes in samples from Southeast Asia associated with "yellow rain

ceive sporadic reports of chemical warfare at-tacks in Laos. By 1976, the reports had become regular and each succeeding year showed steady increases in the number of chemical attacks. The attacks are still continuing. Much of the chemical warfare activity in Laos centers around the areas that are highlighted in Fig. 1 (Haig, 1982). Most of these attacks have been directed against H'Mong villages. The villages attacked have usually been centers of resistance activity. The attacks in Laos have been almost exclusively air attacks with the chemical agents delivered by aircraft or heli-copter spray, bombs, and air-to-surface rock