Lung inflammation and lack of genotoxicity in the comet and micronucleus assays of industrial multiwalled carbon nanotubes Graphistrength © C100 after a 90-day nose-only inhalation exposure of rats

Table 12 Results of the comet assay with and without hOGG1 in the lung, kidneys and liver of male rats 24 h after a 90-day exposure to Graphistrength^© C100

Test groups (n = 5/group)	hOGG1	Air control	Graphistrength^© C100 (mg/m³)			Positive control^a
		0	0.05	0.25	5.0
LUNG
% of DNA in tail^b	-	8.8 ± 5.5	3.4 ± 1.5*	8.2 ± 5.1	4.7 ± 3.7	48.7 ± 3.0**
% of DNA in tail^b	+	20.2 ± 5.2	16.7 ± 5.7	22.3 ± 11.8	17.9 ± 5.9	79.1 ± 7.9**
Relative ratio of ghost cell^c	-	-	1.0	1.2	0.8	0.6**
Relative ratio of ghost cell^c	+	-	2.1**	2.0**	1.3	1.1
KIDNEYS
% of DNA in tail^b	-	7.4 ± 4.4	7.5 ± 4.2	8.2 ± 4.2	9.7 ± 3.1	72.5 ± 5.8**
% of DNA in tail^b	+	22.8 ± 7.4	22.4 ± 7.3	23.4 ± 8.4	24.3 ± 8.0	74.0 ± 5.9**
Relative ratio of ghost cell^c	-	-	1.6	0.9	1.5	2.8**
Relative ratio of ghost cell^c	+	-	1.1	1.6*	1.7**	0.6*
LIVER
% of DNA in tail^b	-	3.8 ± 3.1	3.4 ± 1.6	1.8 ± 1.0	5.5 ± 2.9	71.2 ± 9.1**
% of DNA in tail^b	+	11.6 ± 6.4	7.5 ± 1.5	7.7 ± 1.1	9.6 ± 3.0	78.6 ± 3.7**
Relative ratio of ghost cell^c	-	-	0.2	0.5	2.8**	4.9**
Relative ratio of ghost cell^c	+	-	0.5*	0.2**	1.1	1.7**