Figure 2. The levels of heavy metal elements in the whole blood, liver, lung, cerebral cortex and kidney of rats.

Five heavy metals, including Al, Pb, Cu, Mn and As, showed significantly higher levels in groups treated with PM_2.5 than control group. The results were shown in (a–e), representing Pb, Mn, Al, As and Cu respectively. ^*P < 0.05 = significant as compared to the control; ^#P < 0.05 = significant as compared to the 10 mg/kg group; ^&P < 0.05 = significant as compared to the 20 mg/kg group (n = 12).