Why the ATSDR 1,000 ppt Standard is NOT appropriate as a state residential cleanup standard
The ATSDR 1,000 ppt was calculated based on a 1984 assessment by the Centers for Disease Control that is NOT consistent with the current assessment of dioxinís cancer hazard
The 1,000 ppt level was NOT derived as a "safe" level. It was thought to be a level that could be associated with health effects. Cleanup levels are traditionally set at levels BELOW those thought to cause health effects. Therefore, it is not accurate to suggest that levels below 1,000 ppt pose no risk.
Referring to the ATSDR 1,000 ppt level as a cleanup level is not accurate. The 1,000 ppt level is NOT used by ATSDR for that purpose.
The 1,000 ppt level was NOT developed to serve as a standard for cleanup for residential areas
The 1,000 ppt level does NOT represent a line between safe and unsafe conditions, although it has been used in that way
The EPA has been reviewing dioxinís toxicity for more than 10 years. Their review has been repeatedly peer-reviewed, but political wrangling and the power of the chemical industry have prevented its release. The draft document concludes that dioxin is more toxic than previously thought
If the EPA reassessment were released, the stateís cleanup standard would be more stringent, not weaker, based on a new interpretation of studies on dioxinís toxicity. The state standard would be between 12 and 53 ppt.
The 1,000 ppt level does NOT consider non-cancer health effects that may occur when people are exposed to dioxin at even lower levels than those associated with cancer. The most sensitive endpoint for dioxinís toxicity is thought to be neurobehavioral impacts.
If the state were to use the 1,000 ppt standard, the issue of dioxinís toxicity will continue to plague the state. When the Dioxin Reassessment is finalized, the EPA will again look at sites and reassess previous actions to determine if they are protective. So a cleanup to 1,000 ppt today will not guarantee that the issue will go away. It could just keep coming up unless contamination is cleaned up to a reasonable and legitimate standard.
Cleanup levels in different states and regions in the US:
Region III EPA
(Delaware, Maryland, Pennsylvania, Virginia, West Virginia, and the District of Columbia), 4.3 ppt TCDD
Region IX EPA
(Arizona, California, Nevada, Hawaii), 3.9 ppt
Oregon, 3.9 ppt
Massachusetts, 4.0 ppt
North Carolina, 4.1 ppt
Georgia, 4.8 ppt
Washington, 8.7 ppt
Florida, 7.0 ppt
Iowa, 14 ppt
Arizona, 38 ppt
Michigan, 90 ppt
Pennsylvania, 120 ppt
Minnesota, 200 ppt
Source: The Ecology Center,www.ecocenter.org 6/6/04