Complex sentence: 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.
Split into simpler sentences: In 1981, after noting etiological similarities, U.S. chemical weapons experts claimed to have matched samples taken from an alleged attack in Laos to trichothecene signatures. They hypothesized that T-2 was discovered accidentally through contamination and later weaponized.