The neutral red uptake (NRU) cytotoxicity test is based on the ability of viable cells to incorporate and bind neutral red (NR).
| Test Model | Balb/c 3T3 cells |
| Replicates | Six per group (preliminary and confirmatory study) |
| Assay controls | Negative control: Aqueous or organic Solvents Positive control: Sodium lauryl sulphate Eight different test item concentrations |
| Exposure time | 44 – 48 hours |
| Test item quantity | 1.0 gram |
| End point | Ability of viable cells to incorporate and bind neutral red (NR) |
| Data delivery | % of viability of cells |
| Timeline | 3 – 4 weeks |