Table 1.
Toxicity of 2D Materials and their Compound Materials
| Materials | Exposure Method | Species/Cell Types | Biological Outcomes | Literature |
|---|---|---|---|---|
| 2D and 2D Layered Materials | ||||
| MnO2 | cell culture | Human breast cancer cells (MCF-7) | ~45 % viability after exposure to 100 ppm PEG coated nanoplates (width 20–70 nm) for 24 h | 128 |
| MoO3 | cell culture | Human breast cancer cells (iMCF-7 and MCF-7) | ~ 40–50 % viability after 48 hr exposure to 400 ppm as-prepared nanoplates (400 nm × 100–200 nm) | 127 |
| TiO2 | IP injection | mice (C57) | PEG coated TiO2 nanosheets (anatase, lateral dimension 92.5 nm) accumulate in liver and spleen and cause appreciable toxicity in liver at 10 µg/g-body weight. |
126 |
| WS2 | cell culture | mouse mammary gland cancer cells (4T1), Human Cervix cancer cells (Hela), human kidney cancer cells (293T) and human lung cancer cells (A549) |
~ 50% viability for 4T1, Hela, 293T after 24 hr exposure to 100 ppm nanosheets; ~30% viability for A549 after 24 hr exposure to 400 ppm nanosheets (lat. dim. ~500 nm, thickness ~20 nm) |
129,111 |
| MoS2 | cell culture; oropharyngeal aspiration |
human Cervix cancer cells (Hela) and human lung cancer cells (A549); Escherichia coli (E. coli) K12; human leukemia monocytes (THP1) and human lung cells (BEAS-2B) and C57Bl/6 mice; rat kidney cells (RAMEC) and rat Adrenal Gland cells (PC-12) |
~70–95% viability for Hela cells exposed to 160 ppm PEGylated nanosheets (50nm × 2nm); ~50% viability for A549 cells exposed to 400 ppm nanosheets (~400x~4.5 nm); cell viability decreases as extent of exfoliation increases in panel of MoS2 nanosheets; Aggregated but not dispersed MoS2 nanosheets induce acute lung inflammation in mice; no loss of viability in RAMEC and PC 12 cells exposed to few-layer MoS2 nanosheets at doses up to 100 µg/ml. |
110–113, 119, 123 |
| WSe2 | cell culture media | human lung cancer cells (A549) | ~30 % viability for A549 after exposure to 400 ppm as-exfoliated materials (lateral dimension ~200 nm, thickness ~7 nm) for 24 hrs |
111 |
| Bi2Se3 | cell culture media; IP injection |
mouse liver cancer cells (H22); male mice (C57) | ~90 % viability for hepatocarcinoma H22 cells after exposure to 200 ppm PVP-coated nanosheets (rhombohedral phase, lateral dimension 90 nm, outer layer 3.6 nm, inner thickness 21 nm) for 24, 48, 72 h; IP injection of PVP- coated Bi2Se3 nanosheets (50 nm × 6 nm) in mice at doses up to 20 mg/kg produced no obvious adverse effects on growth or changes in body weight up to 90 days, and a panel of measurements focused on immune response, hematology, and biochemistry suggested “limited biological damage” |
125, 130 |
| TiS2 | cell culture media and intravenous injection |
mouse mammary gland cancer cells (4T1); mice (Balb/c) |
No obvious toxicity with up to 100 pm TiS2-PEG nanosheets (cubic phase, lateral dimension ~100 nm) to 4T1 cells and no obvious damage to mouse organs up to the 2 mg/mL, 200 µl TiS2-PEG injection (20 µg/g-body weight) |
124 |
| Other Nanomaterials Forms (Particulate or Fibrous) | ||||
| MnOx | Inhalation; cell culture |
rats (Fischer 344); rat liver fibroblasts (BRL 3A) |
Manganese oxide nanoparticles (30 nm) altered gene expression in olfactory bulb, frontal context, midbrain, striatum, cerebellum rats after 11 days of inhalation; 60% viability for BRL 3A cells exposed to 250 ppm particles for 24 h. |
131,132 |
| h-BN | cell culture | human embryonic kidney cells (HEK293); rat adrenal gland cells (PC-12) |
Nontoxic up to 100 ppm for HEK293 cells after exposure to h-BN multiwalled nanotubes (diameter 20–30 nm, length up to 10 mm) for 4 days; 20% decrement of metabolic activity for PC12 cells after exposure to 100 ppm bamboo-like nanotubes (diameter 50 nm, length 200–600 nm) for 9 days. |
133, 134 |
| MoS2 | cell culture | human lung cancer cells (A549), human bone marrow leukemia cells (K562), human embryonic skin fibroblasts (CCC-ESF-1) |
No cytotoxicity for A549, K562, CCC-ESF-1 cells after exposure to 3.5 ppm nanoparticles (hexagonal phase, 120 nm) for 48 h |
135 |
| MoO3 | cell culture | rat fibroblasts (BRL 3A); human bone osteosarcoma cells (U2OS ) |
~ 60 or 50 % layered double hydroxide (LDH) leakage and ~20 or ~40 % viability for BRL 3A cells after exposure to 250 ppm nanoparticles (30 or 150 nm) for 24 h; No cytotoxicity for U2OS cells after exposure to 4 ppm nanospheres (290.4 ± 66.7 nm) for 2 h; |
132, 136 |