A risk assessment is one of the cornerstones in biological safety, and a required process to effectively reduce hazards. The following should be considered when assessing risks of toxins of biological origin.
- Risks inherent to the procedure
- Inoculation during animal protocols
- Inhalation of aerosols
- Static build up from powders
- Use of sharps
- Aerosol-generating procedures
- Amount of toxin being handled
- Availability of treatments, vaccines, and antitoxins
- Training and experience of users
- Intoxication and lethal dose data
- Acute and chronic health effects
- Engineering controls
- Availability and efficacy of safety equipment and PPE
Select Agents and Toxins
Permissible Toxin Amounts
The following toxins are not regulated if the amount under the control of a principal investigator, treating physician or veterinarian, or commercial manufacturer or distributor does not exceed, at any time, the amounts indicated in the table below.
| HHS Toxins [§73.3(d)(7)] |
Amount |
| Abrin | 1000 mg |
| Botulinum neurotoxins | 1 mg |
| Short, paralytic alpha conotoxins | 100 mg |
| Diacetoxyscirpenol (DAS) | 10,000 mg |
| Ricin | 1000 mg |
| Saxitoxin | 500 mg |
| Staphylococcal Enterotoxins (Subtypes A, B, C, D, and E) | 100 mg |
| T-2 toxin | 10,000 mg |
| Tetrodotoxin | 500 mg |
