Table 2.

The amount of urinary SPMA in mice exposed to benzene (μg/g creatinine, mean ± S.D., n = 6)

Exposure route	Dose (ppm/mg/kg)				Ptrend
	0	1	10	100
Inhalation	0.32 ± 0.11	1.77 ± 1.17	31.66 ± 9.12a	79.74 ± 9.65a	<0.0001
Oral gavage	0.40 ± 0.10	1.80 ± 1.40	43.63 ± 12.06a	92.51 ± 5.53a	0.044

^a p < 0.05, compared with the corresponding control group, as determined by independent-sample t test or assessed with one-way ANOVA followed by Bonferroni post-test.