I don't know about you, but the idea of diesel particulates (soot) lodging themselves on my brain doesn't sit well with me. While scientists and researchers have known for some time that diesel soot clings to our grey matter, just recently Dutch scientists were able to convince 10 people to sit in a room filled with diesel exhaust so that they could monitor their brain waves. Not surprisingly, their brains showed signs of "stress" just thirty minutes into this operation. We're not going to argue with these results... in fact we thought it was just common knowledge that breathing exhaust fumes, whether from either gas or diesel burning cars, was a bad idea. Ah well, at least we now have scientific data on the topic.