Tetrodotoxin (TTX)

Download TTX PDF


Natural Source

TTX naturally occurs in the skin, intestine and liver of some fish in the order Tetraodontidae. Examples include puffer fish, porcupine fish, ocean sunfish, and some species of newts and salamanders.

Laboratory Source

Isolated toxin


The toxin is a chemical with a molecular formula of C11H17N3O8. The formula weight is 319.27. TTX is a neurotoxin that blocks the flow of sodium ions in sodium channels. This blocks the conduction of nerve impulses.

Health Hazards

Route of Entry

Inhalation, ingestion, absorption, and injection

Signs and Symptoms

Paresthaesias, dizziness, gastrointestinal symptoms, and ataxia. Toxication can progress to paralysis and death within hours of ingesting the naturally occurring toxin. 

Toxicity Dose Data

Median LD50 for humans is 334 μg/kg

Medical Precautions/Treatment


No rapid diagnostic assays are currently available.


None available


None available


No antidote available. Administer supportive care (artificial respiration to support breathing).

Emory Requirements

Report all exposures

Supplemental References


Biosafety in Microbiological and Biomedical Laboratories 

Essentials of Toxicology

Klaassen CD, Watkins JB. 2003. Casarett & Doull's Essentials of Toxicology. New York (NY): McGraw-Hill.

Guide to Hazardous Properties

Patnaik P. 2007. Guide to Hazardous Properties of Chemical Substances. 3rd Edition. Hoboken (NJ): John Wiley and Sons.

Biological Safety: Principles & Practices

Flemming DO, Hunt DL. 2006. Biological Safety: Principles and Practices. 4th Edition. ASM Press.

Spill Procedures


Notify others working in the lab. Rinse gloves with decontamination solution and don new gloves. Cover area of the spill with paper towels and apply decontamination solution, working from the perimeter towards the center. Exit and keep others from entering the laboratory. Allow 1 hour of contact time before entering the laboratory without respiratory protection. Cleanup and dispose of spill materials


Contact Emory's Biosafety Officer (404-727-8863),
the EHSO Office (404-727-5922), or
The Spill Response Team (404-727-2888).

Exposure Procedures

Mucous membrane

Flush eyes, mouth or nose for 15 minutes at eyewash station.

Other Exposures

Wash area with soap and water for 15 minutes.


Immediately report incident to supervisor, complete an employee incident report in PeopleSoft.

Medical Followup 

7am-4pm (OIM): EUH (404-686-7941) EUHM (404-686-7106) WW (404-728-6431)

After Hours: OIM NP On Call 404-686-5500 PIC# 50464

Needle Stick (OIM): EUH (404-686-8587) EUHM (404-686-2352)

Yerkes: Maureen Thompson Office (404-727-8012) Cell (404-275-0963)



1.0 to 2.5% sodium hypochlorite 


Autoclaving is not an effective method of physical inactivation of TTX.

Personal Protective Equipment (PPE)

Minimum PPE Requirements

At minimum, personnel are required to don gloves, closed toed shoes, lab coat, and appropriate face and eye protection prior to working with TTX. Additional PPE may be required depending on lab specific SOPs.

Additional Precautions

Depending on the risk assessment, respirators may be required when working with TTX. Fit testing and training is required annually per Emory's Respiratory Program (PDF).

Additional Requirements

Regulatory Requirements

TTX is select agent and is regulated under the federal regulation 42 CFR Part 73. TTX is not regulated if the amount under the control of a principal investigator, treating physician or veterinarian, or commercial manufacturer or distributor does not exceed 100 mg, at any time. Possession of select agent toxins above the maximum amount without CDC registration is a criminal offense and punishable by up to five years in prison and/or $500,000 in fines. Please contact the Biosafety Officer if you do not have biosafety approval for working with TTX.