Semiquantitative scores of lung inflammation within alveolar, bronchiolar, perivascular and pleural regions, as well as particle-associated inflammation throughout the lungs. In general, inflammatory scores were higher following exposure to CA PM, compared to controls or CH PM exposure. However, only the inflammation of the alveoli was significantly different following exposure to CA PM compared to control (* p<0.05). In contrast, particle-associated inflammation was significantly greater in mice exposed to CH PM, compared to control (* p<0.05) or to CA PM (# p<0.05). This difference is likely to be due to the greater amounts of black soot found in CH PM.