Table 1

Body weights and food consumption

Experimental group	Exposure time(days)	Number of animals	Body weight (g)	Mean food consumption(g/day)
Values are expressed as mean (SD).
Significant differences among groups at p<0.05 (one way analysis of variance followed by post hoc pairwise multiple comparisons procedures, Tukey’s test) are indicated as follows:
*vs room air 3 days.
†vs room air 21 days.
‡vs room air 49 days.
§vs NO₂ 7 days.
¶vs NO₂/room air.
**vs NO₂ 3 days.
††vs NO₂ 21 days.
All animals	0	42	181 (5)	–
Room air	3	4	210 (3)†‡§¶	15.9 (2.2)**§††¶
Room air	21	8	250 (13)‡*§††¶	13.6 (1.2)‡**§††¶
Room air	49	6	297 (13)†*§††	18.6 (2.7)†**§††
10 ppm NO₂	3	6	189 (9)†‡¶	5.8 (3.6)*†‡††¶
10 ppm NO₂	7	6	183 (5)*†‡††¶	7 (2.8)*†‡††¶
10 ppm NO₂	21	6	205 (11)†‡§¶	9.4 (1.8)†‡*§
10 ppm NO₂/room air	21	6	201 (8)†‡¶	9.2 (1.9)†‡*§
10 ppm NO₂/room air	+ 28		280 (11)†*§††	19.8 (2.1)†*§