Table 2

Groups of rats that were administered suspensions of particles with diameters:
10 nm	50 nm	1 μm	Controls (water)
Iron content (mg/kg raw tissue)
200 ± 9*	257 ± 8*+	258 ± 15*+	141 ± 5+
Difference between group administered magnetite and controls
59 ± 10	116 ± 9+	117 ± 16+	-

*designates values that are statistically significantly different from control value;
+ same from the value for the group of rats administered 10-nm particles (P<0.01 by Student’s t-test)

Table 2: Iron content of rat lung tissue 24 hours after intratracheal instillation of 2 mg of magnetite particles of various sizes or distilled water (X±s.e.)