Chemicala and Heat Inactivation of Toxins
| Toxin | 2.5% NaOCI + 0.25N NaOH | 2.5% NaOCI | 1% NaOCI | Autoclaving |
| T-2 mycotoxin | Yes | No | No | No |
| Brevetoxin | Yes | Yes | No | No |
| Microcystin | Yes | Yes | Yes | No |
| Tetrodotoxin | Yes | Yes | Yes | No |
| Saxitoxin | Yes | Yes | Yes | No |
| Palytoxin | Yes | Yes | Yes | Yes |
| Ricin | Yes | Yes | Yes | Yes |
| Botulinum | Yes | Yes | Yes | Yes |
| Staphylococcal enterotoxin | Yesb | Yesb | Yesb | Yesb |
a = 30 minute exposure to various concentrations of sodium hypochlorite with or without sodium hydroxide.
b = assumed inactivation
Conotoxin
Conotoxin inactivation depends on the presence or absence of disulfide bonds.
- For conotoxins with disulfide bonds, incubate with an excess of dithiothreitol (DTT) (usually 10-20mM buffered solution, pH8.7) for at least 1 hour at room temperature or 30 minutes at 50oC. Add an equal volume of 50-100mM solution of iodoacetamide (buffered solution, pH8.7) and incubate for 1 hour at room temperature.
- For conotoxins without disulfide bonds, incubate in a closed glass vial with 6N HCl for 24 hours at 90-110oC.
For skin contact, use soap and water to remove toxin burden. Mycotoxins are dermally active; however, washing even 1 hour after contact with T-2 can prevent dermal toxicity.
Recommendations:
- For complete inactivation of T-2 mycotoxin and brevetoxin, all liquid samples, accidental spills, nonburnable waste, and cages and bedding from animals exposed to these toxins, soak in 2.5% NaOCl + 2.25%N NaOH for 4 hours.
- All burnable waste from toxins should be incinerated at temperatures in excess of 1500oF (815oC).