ROCKPORT, Ind. (CBS) — A new report shows Indiana’s factories topped the nation in toxic water pollution discharge in 2010.

As WBBM Newsradio’s John Waelti reports, the report by Washington, D.C.-based Environment America found that Indiana plants dumped more than 27 million pounds of pollutants into the state’s waterways.

LISTEN: WBBM Newsradio’s John Waelti reports

The group says one company in particular – AK Steel – charged 24 million pounds of pollutants into the Ohio River at its Rockport mill. That figure is believed to make up about two thirds of the nation’s entire total discharges into the Ohio River, reports the Courier-Journal of Louisville, Ky.

Some of the pollutants could be dangerous even in small amounts, including mercury – a neurotoxin that can accumulate in fish and elsewhere in the environment, Kentucky Waterways Alliance executive director Judy Petersen told the Associated Press.

Indiana Department of Environmental Management spokeswoman Amy Hartsock downplayed the big discharge number reported for AK Steel. She says the data reported to the federal government “cannot be used to draw conclusions to human health or the environment.”

The next highest polluting states, in order, were Virginia, Nebraska, Texas, and Louisiana, the Associated Press reported.

(TM and © Copyright 2012 CBS Radio Inc. and its relevant subsidiaries. CBS Radio and EYE Logo TM and Copyright 2012 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed. The Associated Press contributed to this report.)

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