The NAS while making this statement also said that the government would not know just how dangerous Dioxin really is until researchers try different ideas and change the way in which they assess the risks.
It was reported that NAS was asked by the Environmental Protection Agency (EPA) and other federal agencies to evaluate the assessment on dioxin's risk of causing cancer by the EPA, which has been an ongoing work for 15 years. It was explained that dioxin and related compounds are produced as by products of certain industries, particularly those that involve chlorine. These by products tend to break down very slowly, and research has found that they are present throughout the environment and in the bodies of almost all people in the US.
The EPA, in its preliminary report in 2003 said that dioxin is a dangerous carcinogen, but experts from outside raised questions when asked to review the report by the agency on the technique used by them to calculate the extent of the danger. NAS stated that it is very clear about the likelihood of dioxin being carcinogenic in humans, but it suggests that to know just how carcinogenic, the modes used for the study must be changed., says
Thomas McKone, a member of the panel and senior scientist at the Lawrence Berkeley National Laboratory in Berkeley, California, explained that there are not enough data about dioxin in humans to determine the true risk, so the EPA has had to rely on animal studies. He further said that the test animals would have to be exposed to an extremely high dose of dioxin, but that the doses that the humans are exposed would probably be a thousand times less, which would make the interpretation of relevant data difficult.
The environmental groups have meanwhile alleged that the report is merely an attempt to try and delay the release of the final EPA risk assessment on dioxin. The EPA estimates that dioxin emissions in the environment have been reduced by 92 percent since 1987 through regulations and industry efforts.