|  | Extremely toxic | Very toxic | Toxic | Harmful | Not toxic |
---|---|---|---|---|---|---|
(<0.1 mg/L) | (0.1-1 mg/L) | (1–10 mg/L) | (10–100 mg/L) | (>100 mg/L) | ||
SWCNT | invertebrates | X | X | X | Â | Â |
 | vertebrates |  | X |  |  | X |
DWCNT | invertebrates | Â | X | X | X | Â |
 | vertebrates |  |  | X |  | X |
MWCNT | invertebrates | Â | X | X | X | Â |
 | vertebrates |  |  |  | X | X |