Fig. 4
From: Persistent effects of Libby amphibole and amosite asbestos following subchronic inhalation in rats
Long-term stop-exposure inhalation study: lung fiber burden. Numbers of all asbestos structures (any structure with L ≥0.2 μm; top panel) and WHO fibers (L ≥5 μm, L/D ≥3; bottom panel) recovered in five lung lobes (LRT) of rats exposed to AM or LA for 13 weeks (5 days/week for 13 weeks; 6 hr/day) and evaluated at 1 day, 1 month, 3 months, or 18 months after the end of the exposure. Values in legend represent target mass concentrations (mg/m3). Results show mean values ± SE (n = 4 rats per group). P < 0.05 †vs. all other groups; # vs. LA 1.0 group