Table 1

Summary of recent in vivo experiments carried out with CNTs

Type of CNT

System

Summary results

Reference


SWCNTs

(Carbon nanotech Inc. Tx).

Ø: 0.8–1.2 nm

L: 0.1–1 μm

Pharyngeal deposition in C57Bl/6 mice lung (40 μg/mouse). Observation 4 hours post exposure.

Gene expression in lung and blood: Upregulation of genes involved in inflammation, oxidative stress, coagulation, tissue remodeling. Increased percentage of polymorphonuclear leucocytes (PMN) in blood and bronchoalveolar lavage (BAL).

[30]


SWCNTs.

240 nm (mode, aerodynamic diameter; in number)

Inhalation (4 days) in mice – 5 mg/m3

Short and mean term responses (1, 7, 28 days)

Lung analysis: Inflammation – Granulomas – Fibrosis – Mutation of K-ras

[58]


4.2 μm (mode, aerodynamic diameter; in mass)

Laryngeal deposition (10 μg/mouse).

Short and mean term responses (1, 7, 28 days)

Lung analysis: Inflammation – Granulomas – Fibrosis -

No mutation of K-ras. Lower effects compared to inhalation.


MWCNTs.

Ø: 40–60 nm

L:0.5–500 μm

Intratracheal deposition in rats.

One to 7 mg/kg. Short/mean term responses (1 to 90 days)

Inflammation; dose-dependent thickening of the alveolar lining

Particles still present after 3 months

[56]


MWCNTs grinded, unheated, heated to 600°C, 2400°C; 2400°C then grinded.

Ø: 20–50 nm

L: 0.7 ± 0.07 μm

Intratracheal deposition in rats, 2 mg/rat. Short-term response (3 days); mean-term (60 days)

Inflammation (3 days). Granulomas (60 days).

Effects of heated CNTs lower than unheated.

Grinding restored the effects.

[57]


MWCNTs.

Ø: 40–60 nm

L:0.5–500 μm

Intratracheal deposition in rats. One to 7 mg/kg. Short/mean term responses (1 to 90 days)

Inflammation; dose-dependent thickening of the alveolar lining

Particles still present after 3 months

[56]


MWCNTs

(Mitsui & Co., LDT)

Ø: ≅ 80 nm

L: 10–20 μm

Pharyngeal deposition in C57Bl/6 mice lung (40 μg/mouse). Observation 4 hours post exposure.

Gene expression in lung and blood: Upregulation of genes involved in inflammation, oxidative stress, coagulation, tissue remodeling. Increased percentage of polymorphonuclear leucocytes (PMN) in blood and bronchoalveolar lavage (BAL).

[30]


MWCNTs

Shenzhen nanotech

Ø: 500 nm;

L: 10 μm

Inhalation (≈ 32 mg/m3) in mice for 5, 10, 15 days; deposition ≈ 0.07, 0.14; 0.24 μg/mouse. Short-term response (8, 16, 24 days)

Small aggregates entering the alveolar wall

Cell proliferation and thickening of alveolar walls

[59]


Tracheal deposition: 50 μg/mouse

Eight and 16 days: clumps deposited on lining wall of bronchi, no inflammation – 24 days: inflammation.

Clumps in the alveoli destruction of alveolar structure


Jaurand et al. Particle and Fibre Toxicology 2009 6:16   doi:10.1186/1743-8977-6-16

Open Data