Fact Sheet – November 2004
Congressional Request
In September 2003, the Senate Appropriations Committee directed the Agency for Toxic Substances and Disease Registry (ATSDR) to develop a Report to Congress that assesses the level of lead poisoning of families, especially children, at the Tar Creek Superfund Site in Oklahoma (Senate Report 108-143, September 5, 2003, page 86; Departments of Veterans Affairs and Housing and Urban Development, and Independent Agencies, Appropriations Bill, 2004).
Senator James Inhofe (R-OK), chairman of the Senate Environment and Public Works Committee, further elaborated in the Congressional Record (Senate, January 22, 2004): “I am urging ATSDR in collaboration with the Oklahoma State Department of Health to work to identify significant sources and pathways of exposure to lead that may be contributing to elevated blood lead levels in children at the Tar Creek Superfund Site.”
ATSDR Findings
From September 2003 to May 2004, ATSDR staff reviewed blood lead and environmental data from the Ottawa County Health Department, the Oklahoma State Department of Health, and the U.S. Environmental Protection Agency to define the extent of lead exposure among children in the Tar Creek area and to identify potential sources and pathways of exposure.
Potential Sources of Lead Exposure
Mine tailings and lead-based paint are two potential sources contributing to lead exposures among children residing in the Tar Creek Site area. However, the relative contributions of the two sources to the blood lead levels of people living in the Tar Creek Superfund Site area cannot be determined from existing information.
Decrease in Blood Lead Levels
During 1995-2003, the average blood lead level and the percentage of elevated blood lead levels (greater than or equal to 10 micrograms per deciliter) decreased among children aged 1-5 years living in the Tar Creek area and tested for lead. In 2003, the average blood lead level and the percentage of elevated blood lead levels among children tested for lead who lived in the Tar Creek area were slightly higher than those for all children tested in the United States during 1999-2000. The Centers for Disease Control and Prevention’s National Health and Nutrition Examination Survey (NHANES) data indicate that among U.S. children aged 1-5 years during 1999-2000, 2.2% had elevated blood lead levels, with an average of 2.2 micrograms per deciliter. This difference can be explained by the fact that the U.S. data is a representative sample of the United States, and the data collected for tested children at the site are not representative of all children living at the Tar Creek site.
Potential Risk of Exposure Exists
The data seen so far are reassuring; blood lead levels in children both at Tar Creek and nationally are decreasing. At the same time, there is a continued risk of exposure to lead at the Tar Creek site from chat piles, mill and mine residue, and flotation ponds. Elimination of the sources of lead contamination will achieve long-term protection of children.
ATSDR Recommendations for Future Action
ATSDR recommends these actions to address concerns expressed by the community and to protect the health of Tar Creek residents:
- Continue to identify children with elevated blood lead levels and to reduce or eliminate their exposures to lead.
- Continue to provide lead exposure prevention education to people potentially affected by the site.
- Provide periodic reports of Tar Creek and Ottawa County child blood lead statistics to the communities affected by the Tar Creek Site.
- Complete remediation of residential properties.
- Complete the investigation of chat piles, mill and mine residues, and flotation ponds.
- Assess the risk for lead exposure from using mine tailings (chat) for commercial and residential purposes, including processing and transporting the material.
- Correlate lead isotopes in the environment and in children’s blood to identify specific environmental sources of lead for those who have elevated blood lead levels.
- Evaluate the health risks of other site-related contaminants and physical hazards.
For More Information:
ATSDR Regional Representative Jennifer Lyke may be contacted toll-free at 1-800-533-3508 or at 214-665-8362. ATSDR Health Communication Specialist LaFreta Dalton may be contacted toll-free at 1-888-422-8737.