Table 1

Metabolic balance studies

	Urine	Feces	Blood	Brain	Liver	Digestive tract	Kidney	Ovaries/testes	Fat	Carcass	Muscle	Cage	Total
Group A
M n = 3
ppb			0.15 ± 0.02	0.10 ± 0.02	0.22 ± 0.04	0.73 ± 0.29	0.20 ± 0.05	0.12 ± 0.02	0.09 ± 0.02	0.11 ± 0.02	0.12 ± 0.01
%	57.5 ± 4.8	13.7 ± 2.5	0.17	0.02	0.31	2.15	0.04	0.05	0.08	2.65	0.02	1.52	78.1
F n = 3
ppb			0.14 ± 0.02	0.08 ± 0.01	0.17 ± 0.03	0.58 ± 0.21	0.16 ± 0.03	0.12 ± 0.03	0.09 ± 0.01	0.12 ± 0.05	0.12 ± 0.05
%	40.0 ± 4.9	22.5 ± 3.6	0.13	0.02	0.21	1.44	0.04	0.02	0.06	2.87	0.01	0.96	68.2
Group B
M n = 3
ppb			1128 ± 55	667 ± 25	1743 ± 24	7944 ± 2485	1385 ± 136	1118 ± 100	481 ± 27	746 ± 67	889 ± 19
%	56.9 ± 9.0	16.7 ± 3.6	0.16	0.02	0.25	1.99	0.03	0.04	0.02	1.81	0.01	1.04	78.9
F n = 3
ppb			1311 ± 235	621 ± 45	1729 ± 143	10422 ± 4023	1456 ± 152	869 ± 67	546 ± 72	990 ± 136	795 ± 40
%	40.8 ± 3.9	21.0 ± 3.0	0.15	0.02	0.20	2.93	0.03	0.01	0.03	2.31	0.01	1.15	68.6

Residual levels of radioactivity measured in excreta and tissues of male and female Wistar rats dosed orally with 1 μg/kg (group A) or 10 mg/kg (group B) ³H-labeled 4-n-NP. Results are expressed as nanograms of NP Eq per gram wet weight (ppb) and in percent of the total radioactivity administered to animals over the 4-day study. M, males; F, females.