http://www.physorg.com/ en-us Physorg.com internet news portal provides the latest news on science including: Physics, Nanotechnology, Life Sciences, Space Science, Earth Science, Environment, Health and Medicine. Although the industrial compounds known as polychlorinated biphenols or PCBs have been found in previous air samples collected in the city of Chicago, a University of Iowa researcher says that a new study of Chicago air sampled between November 2006 and November 2007 found PCB11, a byproduct of the manufacture of paint pigments and a potentially toxic substance, present throughout the city. http://www.physorg.com/news141915309.html Space & Earth Mon, 29 Sep 2008 13:55:09 EST news141915309