Applies to: (examples; Faculty,Staff, Students, etc)
Faculty , Staff , Students
Faculty , Staff , Students
Biological toxins are poisonous substances produced by certain microorganisms, animals, and plants. Examples of toxins of biological origin include Diphtheria Toxin, Tetrodotoxin, Pertussis Toxin, Botulinum Toxin, Snake Venom Toxins, Conotoxin and Ricin. Although toxins are derived from biological materials, they do not replicate and are therefore not considered infectious.
However, they may be extremely toxic in very small quantities and must be managed like hazardous chemicals in the workplace. Controls must be in place to ensure staff is protected from exposure. The routes of exposure include inhalation, eye, nose and mucous membrane contact, percutaneous, and skin absorption depending on the diluents used. The main issues of concern in the laboratory are accidental exposures to toxin caused by contact with the mouth, eye, skin and mucous membranes, inhalation of toxin powder or aerosol inadvertently generated, or by needlestick incidents.
Work with toxins of biological origin must be included in your laboratory-specific Chemical Hygiene Plan. Documented toxin-specific hazard training and training on the laboratory-specific standard operating procedures (SOP) is required for all laboratory personnel prior to starting work. The training must include but is not limited to the health and physical hazards of the toxin, signs and symptoms associated with exposure, appropriate work practices, personal protective equipment, and emergency procedures.
Some toxins of biological origin are considered Select Toxins, which the US Departments of Health and Human Services (HHS) and Agriculture (USDA) have determined to have the potential to pose a severe threat to public health and safety, to animal or plant health, or to animal or plant products. The Centers for Disease Control and Prevention (CDC) in their Select Agent Program regulates the possession, use, and transfer of these specific biological agents and toxins. Research work with CDC listed Select Toxins may have additional safety and security requirements including registration with UHSP EH&S and the CDC.
Applies to all faculty, staff and students performing research.
I. LABORATORY PLANNING AND PREPARATION FOR USE
II. ENGINEERING CONTROLS
III. PERSONAL PROTECTIVE EQUIPMENT (PPE)
IV. TOXIN USE PRACTICES (reconstitution, dilution, administration)
V. TOXIN SPILL CLEANUP
Toxin spills must be cleaned up immediately by properly protected and trained personnel.
Liquid Spills
Powder Spills inside a BSC or containment
Powder spills outside of a BSC, fume hood, glove box or approved containment
This information can also be used in reporting to the Emergency Department (ED) after potential exposure. The involved person or supervisor is required to notify EH&S within 24 hours of any spill incident.
VI. ACUTE EXPOSURE
In the event of an exposure incident on campus, any affected employee or student may contact the 24-Hour Exposure Hotline at 1-877-POST-EXP (767-8397) for consultation about the exposure, risks and options.
After administering any necessary initial first aid (e.g. cleaning the wound, flushing eyes or other mucous membrane, etc.), the affected person will immediately notify their supervisor or instructor, who is responsible for submitting an Incident Report form, notifying EH&S of the exposure incident, and contacting Public Safety at 314-446-7233 to arrange transport if needed or requested by the affected person.
If the exposure incident occurs during business hours, affected persons may be transported to Concentra Urgent Care – Midtown (6542 Manchester Road, St. Louis, MO 63139) or Barnes Care (5000 Manchester Avenue, St. Louis, MO 63110) for immediate and confidential medical evaluation and follow-up by a health care professional.
VII. INACTIVATION AND DISPOSAL
According to the CDC, inactivation of a biotoxin means to render the toxin non-functional so that it is no longer capable of exerting its toxic effect. This is different from inactivation of biological agents, which renders the agent non-viable, or no longer capable of growing, replicating, infecting, or causing disease. Inactivation methods used for biotoxins must be specific for the toxin, published and validated, or developed and validated with thorough testing. Note that disinfecting solutions and products may not inactivate biotoxins.
TABLE 1: PHYSICAL INACTIVATION OF SELECTED TOXINS
TOXIN |
STEAM AUTOCLAVE |
DRY HEAT (10 MIN) |
FREEZETHAW |
GAMMA IRRADIATION |
Botulinum neurotoxin |
Yesa |
> 100ºCb |
Noc |
Incompleted |
Staphylococcal Enterotoxin |
Yese |
> 100ºC; refoldsf |
Nog |
Incompleteh |
Ricin |
Yesi |
> 100ºCi |
Noj |
Incompletek |
Microcystin |
Nol |
> 260ºCm |
Non |
ND |
Saxitoxin |
Nol |
> 260ºCm |
Non |
ND |
Palytoxin |
Nol |
> 260ºCm |
Non |
ND |
Tetrodotoxin |
Nol |
> 260ºCm |
Non |
ND |
T-2 mycotoxin |
Nol |
> 815ºCm |
Non |
ND |
Brevetoxin (PbTx-2) |
Nol |
> 815ºCm |
Non |
ND |
Table 1 Notes: ND indicates “not determined” from available decontamination literature.
aSteam autoclaving should be at >121°C for 1 h. For volumes larger than 1 liter, especially those containing Clostridium botulinum spores, autoclave at >121°C for 2 h to ensure that sufficient heat has penetrated to kill all spores.
bExposure to 100°C for 10 min. inactivates BoNT. Heat denaturation of BoNT as a function of time is biphasic with most of the activity destroyed relatively rapidly, but with some residual toxin (e.g., 1-5%) inactivated much more slowly.
cMeasured using BoNT serotype A at -20°C in food matrices at pH 4.1-6.2 over a period of 180 days.
dMeasured using BoNT serotypes A and B with gamma irradiation from a Co source.
eProtracted steam autoclaving, similar to that described for BoNT, followed by incineration is recommended for disposal of SE- contaminated materials.
fInactivation may not be complete depending upon the extent of toxin re-folding after denaturation. Biological activity of SE can be retained despite heat and pressure treatment routinely used in canned food product processing.
gSE toxins are resistant to degradation from freezing, chilling or storage at ambient temperature. Active SEB in the freeze-dried state can be stored for years.
hReferences 15,16 in BMBL.
iDry heat of >100ºC for 60 min in an ashing oven or steam autoclave treatment at >121ºC for 1 h reduced the activity of pure ricin by >99%. Heat inactivation of impure toxin preparations (e.g. crude ricin plant extracts) may vary. Heat-denatured ricin can undergo limited refolding (<1%) to yield active toxin.
jRicin holotoxin is not inactivated significantly by freezing, chilling or storage at ambient temperature. In the liquid state with a preservative (sodium azide), ricin can be stored at 4ºC for years with little loss in potency.
kIrradiation causes a dose-dependent loss of activity for aqueous solutions of ricin, but complete inactivation is difficult to achieve; 75 MRad reduced activity 90%, but complete inactivation was not achieved even at 100 MRad. Gamma irradiation from a laboratory Co source can be used to partially inactivate aqueous solutions of ricin, but dried ricin powders are significantly resistant to inactivation by this method.
lAutoclaving with 17 lb pressure (121-132°C) for 30 min failed to inactivate low molecular weight (LMW) toxins. All burnable waste from LMW toxins should be incinerated at temperatures in excess of 815°C (1,500°F).
mToxin solutions were dried at 150°C in a crucible, placed in an ashing oven at various temperatures for either 10 or 30 min, reconstituted and tested for concentration and/or activity; tabulated values are temperatures exceeding those required to achieve 99% toxin inactivation.
nLMW toxins are generally very resistant to temperature fluctuations and can be stored in the freeze-dried state for years and retain toxicity.
TABLE 2: CHEMICAL INACTIVATION OF SELECTED TOXINS
TOXIN |
NAOCL (30 MIN) |
NAOH (30 MIN) |
NAOCL + NAOH (30 MIN) |
OZONE TREATMENT |
Botulinum neurotoxin |
> 0.1%a |
>0.25 N |
ND |
Yesb |
Staphylococcal enterotoxin |
> 0.5%c |
>0.25 N |
ND |
ND |
Ricin |
> 1.0%d |
ND |
>0.1% + 0.25Ne |
ND |
Saxitoxin |
≥ 0.1%e |
ND |
0.25% + 0.25Ne |
ND |
Palytoxin |
≥ 0.1%e |
ND |
0.25% + 0.25Ne |
ND |
Microcystin |
≥ 0.5%e |
ND |
0.25% + 0.25Ne |
ND |
Tetrodotoxin |
≥ 0.5%e |
ND |
0.25% + 0.25Ne |
ND |
T-2 mycotoxin |
≥ 2.5%e,f |
ND |
0.25% + 0.25Ne |
ND |
Brevetoxin (PbTx-2) |
≥ 2.5%e,f |
ND |
0.25% + 0.25Ne |
ND |
Table 2 Notes: ND indicates “not determined” from available decontamination literature.
aSolutions of NaOCl (≥0.1%) or NaOH (>0.25 N) for 30 min inactivate BoNT and are recommended for decontaminating work surfaces and spills of C. botulinum or BoNT. Chlorine at a concentration of 0.3-0.5 mg/L as a solution of hypochlorite rapidly inactivates BoNT (serotypes B or E tested) in water. Chlorine dioxide inactivates BoNT, but chloramine is less effective.
bOzone (>2 mg/L) or powdered activated charcoal treatment also completely inactivate BoNT (serotypes A, B tested) in water under defined condition.
cSEB is inactivated with 0.5% hypochlorite for 10-15 mi.
dRicin is inactivated by a 30 min exposure to concentrations of NaOCl ranging from 0.12.5%, or by a mixture of 0.25% NaOCl plus 0.25 N NaOH.17 In general, solutions of 1.0% NaOCl are effective for decontamination of ricin from laboratory surfaces, equipment, animal cages, or small spills.
eThe minimal effective concentration of NaOCl was dependent on toxin and contact time; all LMW toxins tested were inactivated at least 99% by treatment with 2.5% NaOCl, or with a combination of 0.25% NaOCl and 0.25N NaOH.
fFor T-2 mycotoxin and brevetoxin, liquid samples, accidental spills, and non-burnable waste should be soaked in 2.5% NaOCl with 0.25% N NaOH for 4 h. Cages and bedding from animals exposed to T-2 mycotoxin or brevetoxin should be treated with 0.25% NaOCl and 0.025 N NaOH for 4 h. Exposure for 30 min to 1.0% NaOCl is an effective procedure for the laboratory (working solutions, equipment, animal cages, working area and spills) for the inactivation of saxitoxin or tetrodotoxin. Decontamination of equipment and waste contaminated with select brevetoxins has been reviewed.
Alternate methods of chemical decontamination: 1 N sulfuric or hydrochloric acid did not inactivate T-2 mycotoxin and only partially inactivated microcystin-LR, saxitoxin, and brevetoxin (PbTx-2). Tetrodotoxin and palytoxin were inactivated by hydrochloric acid, but only at relatively high molar concentrations. T2 was not inactivated by exposure to 18% formaldehyde plus methanol (16 h), 90% freon-113 + 10% acetic acid, calcium hypochlorite, sodium bisulfate, or mild oxidizing.17 Hydrogen peroxide was ineffective in inactivating T-2 mycotoxin. This agent did cause some inactivation of saxitoxin and tetrodotoxin, but required a 16 h contact time in the presence of ultraviolet light.
VIII. TRANSFER OF SELECT TOXINS
Documentation is required for any transfer of the following Select Toxins shown below in any amount (intramurally or extramurally), to any entity or individual. If you plan to transfer any of these Select Toxins you must notify EH&S prior to the transfer. It is the responsibility of the Principal Investigator transferring the Select Toxin to perform due diligence and to keep records for three years.
Name |
Contact Information |
Eric Knoll |