Lead-contaminated soils and chat piles are a means of exposure to the area's population, especially to young children.  A percentage of young children living in the five-city mining area are known to have blood lead levels in excess of the 10 micrograms per deciliter standard set by the Center for Disease Control (CDC).  In 1993, 34% of Native American children had such elevation in blood-lead levels that the concentration was considered to be dangerous to their health. 
In 1996, 67 out of 215 children, or 31.2%, tested in the Tar Creek area had elevated blood lead levels (above 10 micrograms per deciliter).  The efforts of the United States EPA and Oklahoma agencies to cleanup contaminated soils and educate the area's residents has helped reduce the levels in area children by 50%.  

In 2003 only seven out of 250 children, or 2.8%, tested in the Tar Creek area had elevated blood lead levels.  The 2.8 percentage and the 3.04 micrograms per deciliter average blood lead level were still slightly higher than those of children living in the United States as a whole in 1999 and 2000.  People who live in Tar Creek, especially residents of Picher and Cardin, may still be exposed to lead from mine tailings, or chat, because they may live close to chat piles, mill and mine residues, and flotation ponds.

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As you can see in Figure 5 the exposure rate of Picher-Cardin children was higher.

Many Picher and Cardin homes are within 250 feet of tailings. The tailings are transported to the residential properties as a result of deposition of airborne dust from tailings piles and ponds and use of chat as fill and for surfacing driveways.

As of April 2004, over 500 residential properties still needed to be sampled.  57 families who applied for relocation have had their applications reviewed and two have received payment for relocation.

EPA's system for remediating yards gives top priority to homes with children under 7 years of age.  Because all yards have yet to be remediated, young children may continue to be exposed to lead from residential soil.

Over 2,000 residential yards have been cleaned up by Environmental Protection Agency (EPA), and EPA continues to address residential contamination. 

People can ingest soils as an incidental consequence of typical outdoor activities, such as working in the yard, gardening, and playing.  Children are the most sensitive population for lead exposures.

Chronic exposure can deleteriously affect the immune system, blood system, nervous system, and kidneys.  Harmful effects include premature births, smaller babies, decreased mental ability in the infant, learning difficulties, and reduced growth in young children.

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The Picher and Cardin area children still had higher levels than the group as a whole.
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The effort to cleanup the environment will need to be an ongoing project.

Note: Dr. David Bellinger of Childrens Hospital in Boston and Harvard School of Public Health at Harvard Medical School recently completed a pilot study of metals and neuropsychological function in Miami OK middle school-age children. Brenda Zabriskie will go over his findings in class.

His findings have now been published and we received a copy of the report via email December 13, 2005.  We have added his research team's results to our resources website.  The paper is entitled, Neuropsychological correlates of hair arsenic, manganese, and cadmium levels in school-age children residing near a hazardous waste site. 

Obviously, as long as the contamination is there all life is at risk for exposure.











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