CHATTANOOGA, Tenn. (AP) - Health investigators have found elevated lead in soil samples from additional downtown Chattanooga neighborhoods.

The Chattanooga Times Free Press (http://bit.ly/SNjK7H ) reported the discovery comes as state and federal regulators remove contaminated soil found earlier in the Southside neighborhood.

The new samples show lead levels of more than 400 parts per million at 26 sites among 230 tested in areas from Missionary Ridge to St. Elmo. Normal levels for the heavy metal are 50 to 75 parts per million.

EPA cleanup coordinator Perry Gaughan said the source of the contamination is unclear. He said examinations show it did not come from paint shops or iron foundry sand - two common sources.

Information from: Chattanooga Times Free Press, http://www.timesfreepress.com

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