Fig. 4From: Toxicological evaluation of exhaust emissions from light-duty vehicles using different fuel alternatives in sub-freezing conditionsDecrease of CMA compared to control cells assessed with the MTT test after a 24 h exposure of RAW 264.7 mouse macrophages to exhaust gas volume-based doses of PM samples. The Euro 2 doses were one tenth of the doses used with Euro 6. Data reported as mean CMA compared to control cells with standard error of the mean (SEM). Asterisks indicate statistically significant differences from the control (Welch’s ANOVA and Dunnett’s t3 test; p < 0.05)Back to article page