If I remember when I get back, I'll try to find the article I read about nano-scaled particles from gasoline combustion (I think it focussed on mutagenic proper

If I remember when I get back, I'll try to find the article I read about nano-scaled particles from gasoline combustion (I think it focussed on mutagenic properties and in particular the body's inability to move them out of the lungs versus micron-scale which can be expelled more easily). But the VOCs definitely not great. Plus, presumably (I'm guessing), the NOxs from high temp lean combustion in modern gasoline engines are an important factor too?