Table I.
Summary of nickel hydroxide nanoparticles mass concentrations and size for all studies
| Exposure Concentration Group | Low | Mid | High | 1w | 3m | 5m |
|---|---|---|---|---|---|---|
| Nominal mass conc. (µg/m3) | 100 | 500 | 1000 | 100 | 100 | 100 |
| Actual mass conc. (µg/m3) a | 103.2 ± 20.0 b | 565.0 ± 7.1 b | 1204.0 ± 25.7 b | 124.0 ± 31.3 | 129.3 ± 9.36 | 124.5 ± 4.10 |
| Nickel mass conc. (µg Ni/m3) a | 65.4 ± 12.7 | 358.2 ± 4.5 | 763.3 ± 16.3 | 78.6 ± 19.9 | 82.0 ± 5.93 | 79.0 ± 2.60 |
| Number conc. (#/cm3) c | 2.3 E+06 | 1.8 E+07 | 2.8 E+07 | __ | __ | __ |
| Count Median Diameter (CMD, nm) c | 40.1 | 38.4 | 39.1 | __ | __ | __ |
| Geometric Standard Deviation (GSD) c | 1.57 | 1.49 | 1.45 | __ | __ | __ |
| Surface area (m2/g)d | 36.1 | 37.7 | 37.0 |
Abbreviations: conc, concentration; #, total number of particles;
a
Values are the average of two measurements ± SD,
b
Values represents mean ± SEM,
c
Data not shown for long-term studies however values agreed well with those determined for the low exposure short term studies.
d
Values were calculated based on particle size. Functional surface measurements were not performed.