Table 1 Half-time (calculated from k SSA ) and lifetime (estimated from shrinking sphere/fibre models) of micro-sized particles and fibres
From: Dissolution and biodurability: Important parameters needed for risk assessment of nanomaterials
Particles/fibres | Conditions | k SSA | Half-time | Lifetime |
|---|---|---|---|---|
WO3 | As received (aggregated) 36.2 μm particles in artificial airway epithelial lining fluid (pH 7.4) | 2.5 ± 0.3 × 10−5 g tungsten/(cm2·day) [70] | 4 ± 1 daysa |  |
WO3 | Dispersed (individual particles) 36.2 μm particles in artificial airway epithelial lining fluid (pH 7.4) | 0.9 × 10−5 g tungsten/(cm2·day) [70] | 11 daysa |  |
WO3 | Mixture of 36.2 μm particles and 2.4 μm cobalt particles in artificial airway epithelial lining fluid (pH 7.4) | 1.3 ± 0.4 × 10−6 g tungsten/(cm2·day) [70] | 79 ± 23 daysa |  |
WO3 | As received 36.2 μm particles in artificial lung alveolar macrophage phagolysosomal fluid (pH 4.5) | 9.8 ± 2.9 × 10−9 g tungsten/(cm2·day) [70] | 9893 ± 2549a |  |
WO3 | Dispersed (individual particles) 36.2 μm particles in artificial lung alveolar macrophage phagolysosomal fluid (pH 4.5) | 4.3 ± 0.4 × 10−9 g tungsten/(cm2·day) [70] | 21541 ± 1890a |  |
WO3 | Mixture of 36.2 μm particles and 2.4 μm cobalt particles in artificial lung alveolar macrophage phagolysosomal fluid (pH 4.5) | 1.1 ± 0.4 × 10−9 g tungsten/(cm2·day) [70] | 8052 ± 2458a |  |
Talc | 1 μm particles | 1.4 × 10−11 mol Si/(m2.s) [96] |  | 8 yearsb |
Chrysotile | 1 μm fibres pH 2 to 6 at 37°C | 5.9 × 10−10 mol Si/(m2.s) [108] |  | 9 monthsb |
Olivine | 1 μm particles | 7.6 × 10−11 mol Si/(m2.s) [96] |  | 4.8 yearsb |
Quartz | 1 μm particles | 1.4 × 10−13 mol Si/(m2.s) [96] |  | 5000 yearsb |