Figure 5

Urinary 8-oxodG in the urine of mice treated with i) 2× intranasal doses of PBS alone, and ii) 2× intranasal doses of 500 μg ultrafine-carbon black (UF-CB) in PBS alone. Urine was collected 72 h after the second intranasal instillation. 8-oxodG was assayed by liquid chromatography-electrospray ionization-tandem mass spectrometry and results corrected for specific gravity. Bar represents mean, n = 6 per group, * P = 0.055 by unpaired t test.