Aim: To study the biopersistence of a silicon carbide (SiC) nanoaerosol in rat lungs, as time-dependent clearance and spatial distribution. Materials & methods: Sprague-Dawley rats were exposed 6 h/day during 5 days to a SiC nanoaerosol at 4.91 mg SiC/l. SiC biopersistence in rat lungs sections was assessed over 28 days by micro-particle-induced x-ray emission (μPIXE) as 2D maps and by particle-induced x-ray emission (PIXE) for whole-lung quantification. 2D maps were analyzed for SiC spatial distribution as skewness and kurtosis. Results: Half-Time clearance was 10.9 ± 0.9 days, agreeing with PIXE measurements. Spatialtemporal analysis of SiC indicated decreased symmetry and homogeneity. Conclusion: Fast SiC clearance points that current nanoaerosol exposuremay not be enough to trigger lung overload. Spatial distribution shows an asymmetric and nonhomogeneous SiC clearance.