Test results have revealed that the toxic substance splashed on the backs of 10 Washington cows — which killed three of the cows — contained "a strong oxidizing chromium compound."

Chromium compounds tends to be aggressive, corrosive chemicals. FDA officials have declined to identify the exact chromium compound used in the attacks.

Test results on the milk — on both the exposed cows and the rest of the herd — have found the level of chromium in the milk to be "way below" what the EPA allows in drinking water. The FDA has cleared the dairy to start selling its milk again.

For more details on this story from the Seattle Post-Intelligencer, go to http://seattlepi.nwsource.com/local/179274_cow24.html

Seattle Post-Intelligencer, USA Today