Taste Aversive Agents

child with a disgusted expression

The Bottom Line

Taste aversive agents are unpleasant tasting substances often added to potentially dangerous chemicals with the intent of preventing poisoning from accidental ingestion by humans or pets. They are also used in over-the-counter products to help discourage nail-biting and thumb sucking; however, there is no evidence indicating that their usage decreases the incidence or severity of poisonings.

child grabbing bleach bottle from cabinet

The Full Story

Taste aversive agents are substances that are intentionally added to products to help deter inappropriate ingestion and prevent poisonings from occurring. One of the most common taste aversive agents is denatonium benzoate. You might also recognize it by one of its trade names—Denatrol, Bitrex, or Aversion. Denatonium benzoate has an extremely bitter taste that can be detected at minute concentrations (as low as 50 parts per billion). It has thus rightfully earned its reputation as “among the most bitter substances known to man” in the Merck Index and “the most bitter substance in the world” by the Guinness Book of World Records! Other common taste aversive agents include sucrose octaacetate and capsicum (chili peppers). 

Some uses of taste aversive agents include:

  • As alcohol denaturants 
  • In dangerous household chemicals such as: 
    • Antifreeze
    • Animal repellents
    • Veterinary taste deterrent products
    • Rodent baits
    • Pesticides and weed killers
    • Detergents and disinfectants
  • Certain battery and device coatings (e.g., Nintendo Switch game cards)
  • Mask fitting testing
  • Nail-biting/thumb sucking deterrent products

Nail-biting and thumb sucking deterrent products found over-the-counter utilize taste aversive agents like denatonium benzoate and capsicum for their bitter and unpleasant taste properties to help break these habits. Taste aversive agents are generally considered safe with small ingestions.

Though the concept of adding taste aversive agents to substances is appealing, there is currently a lack of published data to demonstrate that adding these compounds to products actually reduces the incidence or severity of poisonings in humans and pets.

When it comes to taste aversive agents in chemicals, perhaps the more concerning potential toxicity would be the actual chemicals to which they are added. Many of these are highly toxic and the presence of a taste aversive agent might cause users to relax normal safety measures. For questions about potential poisonings related to taste aversive agents, use the webPOISONCONTROL® online tool or call 1-800-222-1222. Both options are free of the public, and available 24 hours a day.

Kristina Yee, PharmD
Certified Specialist in Poison Information

Poisoned?

Call 1-800-222-1222 or

HELP ME online

Prevention Tips

  • Do not rely solely on taste aversive agents to prevent unintentional ingestions.
  • Always store potentially harmful chemicals away from areas that could be easily accessed by children and pets.
  • Never transfer products from their original containers into unlabeled containers.

This Really Happened

A man called Poison Control and reported that he does mask fitting tests using Bitrex Testing Solution (1% denatonium benzoate). The solution is bitter and, when they spray it on someone who is getting their mask fitted, the bitter taste will indicate that the mask is not properly fitted. The man reported that he’d been doing mask fittings all day lately because of COVID-19. When he gets home from work he feels nauseated and lightheaded. When he licks his lips, he can taste the bitter product, and he can also smell it. Poison Control indicated that toxicity with this product is limited, but that it could be irritating especially with prolonged exposure. Poison Control recommended that he rinse his skin and mouth well and felt that his symptoms should resolve gradually on their own. The following day, Poison Control called the man and he reported that all of his symptoms had resolved.

For More Information

Bitrex taste test. Edinburgh (UK): Macfarlan Smith [cited 2021 Nov 30].

Humphries M. Duracell is making coin batteries taste horrible on purpose. Pcmag.com; 2020 Sep 30 [cited 2021 Dec 1].

How to stop biting your nails. Rosemont (IL): American Academy of Dermatology [cited 2021 Nov 30].

Taste Aversion. Cincinnati: Wincom Inc. [cited 2021 Nov 29].


References

Baraniuk C. Nintendo switch cartridges “taste so bad.” London: BBC News; 2017 Mar 2 [cited 2021 Dec 1].

Denatonium benzoate. Annapolis (MD): Aversion Technologies [cited 2021 Nov 30].

Humphries M. Duracell is making coin batteries taste horrible on purpose. Pcmag.com; 2020 Sep 30 [cited 2021 Dec 1].

What is Bitrex? Edinburgh (UK): Macfarlan Smith [cited 2021 Nov 30].

White NC, Litovitz T, Benson BE, Horowitz BZ, Marr-Lyon L, et al. The impact of bittering agents on pediatric ingestions of antifreeze. Clin Pediatr. 2009 Nov;48(9):913–21.

Poisoned?

Call 1-800-222-1222 or

HELP ME online

Prevention Tips

  • Do not rely solely on taste aversive agents to prevent unintentional ingestions.
  • Always store potentially harmful chemicals away from areas that could be easily accessed by children and pets.
  • Never transfer products from their original containers into unlabeled containers.

This Really Happened

A man called Poison Control and reported that he does mask fitting tests using Bitrex Testing Solution (1% denatonium benzoate). The solution is bitter and, when they spray it on someone who is getting their mask fitted, the bitter taste will indicate that the mask is not properly fitted. The man reported that he’d been doing mask fittings all day lately because of COVID-19. When he gets home from work he feels nauseated and lightheaded. When he licks his lips, he can taste the bitter product, and he can also smell it. Poison Control indicated that toxicity with this product is limited, but that it could be irritating especially with prolonged exposure. Poison Control recommended that he rinse his skin and mouth well and felt that his symptoms should resolve gradually on their own. The following day, Poison Control called the man and he reported that all of his symptoms had resolved.