TABLE 3.
Selected Studies of In Vitro Toxicity of Synthetic Fibrous Nanomaterials
| Material | Metal content (%) | Cell type | Toxicity assay | Results | Reference |
|---|---|---|---|---|---|
| SWCNT/MWCNT | Fe, Y, Ni (trace) Ni (0.6) | Guinea pig alveolar macrophages | MTT | SWCNT were more toxic than MWCNT at an early timepoint (6hr) | (93) |
| SWCNT/MWCNT | Fe (≤0.009), Ni (<.005–1.86), Co (≤2.8), Mo (≤4.2) | Rat alveolar macrophages | MTT WST-1 LDH release PI/Annexin V | Neither raw material nor highly purified SWCNT and MWCNT were toxic after 24hr | (101) |
| MWCNT/CNF | N.D. | Human lung epithelial (H596) | MTT | MWCNT and CNF showed dose-dependent toxicity CNF>MWCNT | (94) |
| SWCNT | Ni (1.2), Co (1.3) | Human lung epithelial (A549) Rat alveolar macrophages | MTT | SWCNT were nontoxic up to 96hr | (98) |
| SWCNT | Highly purified | Human monocyte-derived macrophages | PI/nuclear morphology | Highly purified SWCNT devoid of contaminating metal were nontoxic | (99) |
| SWCNT | Fe (<0.013) | Human lung epithelial (A549) Human mesothelioma (MSTO-211H) | MTT Hoechst | Unpurified material showed greater toxicity than purified bundles SWCNT were more toxic to MSTO-211H than A549 | (95) |
| SWCNT | N.D. | Human lung epithelial (A549) | MTT Alamar Blue Coomassie Blue | SWCNT showed low acute toxicity following 24hr exposure | (100) |
| SWCNT | Fe (<0.013), Ni (2.4–13.8), Y (0.5–1.6) | Human mesothelioma (MSTO-211H) | MTT Hoechst | SWCNT nanoropes >crocidolite >dispersed SWCNT | (65) |
| MWCNT | N.D. | Murine macrophages Human macrophages Human lung epithelial (A549) | MTT | MWCNT samples were toxic to all cell lines, with EC50 (SWCNT) ≤ EC50 (chrysotile) | (97) |
| MWCNT | Fe (0.47), Co (0.95), Al (0.05) | Rat peritoneal macrophage | LDH release | Ground, but not intact MWCNT, induced dose-dependent toxicity | (66) |
N.D., not determined