PM effects on atherosclerotic lesions in animal studies. The relative increment in atherosclerotic lesions induced by PM exposures over filtered-air controls is displayed (%) Atherosclerotic lesions were assessed by histological analysis of aortic cross-sections, en-face assessment of the whole aorta or ultrasound biomicroscopy depending on the study. Mode of atherosclerotic lesion assessment and references for each study are shown in Table 3. HFD = High fat diet. * p < 0.05 in comparison with the corresponding filtered-air controls.