| Ukrainian opposition leader Viktor Yushchenko was poisoned by TCDD, the most harmful known form of dioxin and a key ingredient of the Vietnam-era herbicide Agent Orange, the scientist who conducted tests on the presidential candidate's blood said Friday. Abraham Brouwer, professor of environmental toxicology at the Free University in Amsterdam, told The Associated Press that the dioxin was TCDD, chemically known as tetrachlorodibenzoparadioxin. Brouwer carried out tests on blood samples sent by Yushchenko's doctors in Vienna. TCDD was a key ingredient of Agent Orange, a herbicide blamed for myriad health problems in U.S. veterans of the Vietnam War and local villagers. It is produced inadvertently during manufacturing processes that use chlorine, such as paper and pulp bleaching. It is also given off by incinerator fumes. There is no commercial production of TCDD. |