A stink bomb or stinkbomb is a device designed to create an unpleasant smell

Odor

An odor or odour is caused by one or more volatilized chemical compounds, generally at a very low concentration, that humans or other animals perceive by the sense of olfaction. Odors are also commonly called scents, which can refer to both pleasant and unpleasant odors...

. They range in effectiveness from simple pranks

Practical joke

A practical joke is a mischievous trick played on someone, typically causing the victim to experience embarrassment, indignity, or discomfort. Practical jokes differ from confidence tricks in that the victim finds out, or is let in on the joke, rather than being fooled into handing over money or...

 to military grade or riot control

Riot control

Riot control refers to the measures used by police, military, or other security forces to control, disperse, and arrest civilians who are involved in a riot, demonstration, or protest. Law enforcement officers or soldiers have long used non-lethal weapons such as batons and whips to disperse crowds...

 chemical agents.

The Guinness Book of Records lists two smelliest substances. One is "US Government Standard Bathroom Malodor"; a mixture of eight chemicals with a stench resembling human feces, only much stronger, designed to test the efficacy of deodorizers and air freshener

Air freshener

Air fresheners are consumer products used in homes or commercial products used in restrooms that typically emit fragrance. There are two broad air freshener categories: continuous action and instant action...

s. Another one, "Who me?

Who me?

Who Me was a top secret sulfurous stench weapon developed by the American Office of Strategic Services during World War II to be used by the French Resistance against German officers...

", is a mixture of five sulfur-containing chemicals and smells like rotting food and carcasses.

Range

At one end of the spectrum, relatively harmless stink bombs consist of ammonium sulfide

Ammonium sulfide

Ammonium hydrosulfide is the chemical compound with the formula SH. It is the salt derived from the ammonium cation and the hydrosulfide anion. The salt exists as colourless, water soluble, micaceous crystals. The compound is encountered mainly as a solution, not as the solid...

, which smells strongly of rotten egg

Egg (food)

Eggs are laid by females of many different species, including birds, reptiles, amphibians, and fish, and have probably been eaten by mankind for millennia. Bird and reptile eggs consist of a protective eggshell, albumen , and vitellus , contained within various thin membranes...

s. When exposed to air, the ammonium sulfide reacts with moisture, hydrolyzes

Hydrolysis

Hydrolysis is a chemical reaction during which molecules of water are split into hydrogen cations and hydroxide anions in the process of a chemical mechanism. It is the type of reaction that is used to break down certain polymers, especially those made by condensation polymerization...

, and a mixture of hydrogen sulfide

Hydrogen sulfide

Hydrogen sulfide is the chemical compound with the formula . It is a colorless, very poisonous, flammable gas with the characteristic foul odor of expired eggs perceptible at concentrations as low as 0.00047 parts per million...

 and ammonia

Ammonia

Ammonia is a compound of nitrogen and hydrogen with the formula . It is a colourless gas with a characteristic pungent odour. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or...

 is released. Other popular substances on which to base stink bombs are thiol

Thiol

In organic chemistry, a thiol is an organosulfur compound that contains a carbon-bonded sulfhydryl group...

s with lower molecular weight, e.g., methyl mercaptan

Methanethiol

Methanethiol is a colorless gas with a smell like rotten cabbage. It is a natural substance found in the blood and brain of humans and other animal as well as plant tissues. It is disposed of through animal feces. It occurs naturally in certain foods, such as some nuts and cheese...

 and ethyl mercaptan

Ethanethiol

Ethanethiol is an organic compound with the formula CH3CH2SH. It consists of an ethyl group, CH3CH2, attached to a thiol group, SH. Its structure parallels that of ethanol, but with S instead of O. The presence of S leads to many different properties, most notably the infamous odour of EtSH...

—the chemicals that give odor to skunk

Skunk

Skunks are mammals best known for their ability to secrete a liquid with a strong, foul odor. General appearance varies from species to species, from black-and-white to brown or cream colored. Skunks belong to the family Mephitidae and to the order Carnivora...

s and are added in minute quantities to natural gas

Natural gas

Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...

 in order to make gas leaks detectable by smell. A variation on this idea is the scent bomb, or perfume bomb, filled with an overpowering "cheap perfume" smell.

At the other end of the spectrum, the governments of Israel

Israel

The State of Israel is a parliamentary republic located in the Middle East, along the eastern shore of the Mediterranean Sea...

 and the United States of America

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 are developing stink bombs for use by their law enforcement agencies

Police

The police is a personification of the state designated to put in practice the enforced law, protect property and reduce civil disorder in civilian matters. Their powers include the legitimized use of force...

 and militaries as riot control

Riot control

Riot control refers to the measures used by police, military, or other security forces to control, disperse, and arrest civilians who are involved in a riot, demonstration, or protest. Law enforcement officers or soldiers have long used non-lethal weapons such as batons and whips to disperse crowds...

 and area denial weapons

Area denial weapons

An area denial weapon is a device used to prevent an adversary from occupying or traversing an area of land. The specific method used does not have to be totally effective in preventing passage as long as it is sufficient to severely restrict, slow down, or endanger the opponent...

. Using stink bombs for these purposes have advantages over traditional riot control agents: unlike pepper spray

Pepper spray

Pepper spray, also known as OC spray , OC gas, and capsicum spray, is a lachrymatory agent that is used in riot control, crowd control and personal self-defense, including defense against dogs and bears...

 and tear gas, stink bombs are believed not to be dangerous, and they are effective at low concentrations.

Prank stink bombs and perfume bombs are usually sold as a 1- or 2-ml

Litre

pic|200px|right|thumb|One litre is equivalent to this cubeEach side is 10 cm1 litre water = 1 kilogram water The litre is a metric system unit of volume equal to 1 cubic decimetre , to 1,000 cubic centimetres , and to 1/1,000 cubic metre...

 sealed glass ampoule, which can be broken by throwing against a hard surface or by crushing under one's shoe sole, thus releasing the odorous liquid contained therein. Another variety of prank stink bomb comprises two bags, one smaller and inside the other. The inner one contains a liquid and the outer one a powder. When the inner one is popped by squeezing it, the liquid reacts with the powder, producing hydrogen sulfide, which expands and pops the outer bag, releasing an unpleasant odor.

Chemicals used

Typically, lower molecular weight volatile organic compounds are used. Generally the higher molecular weight for a given class of compounds, the lower volatility and initial concentration but the longer persistence. Some chemicals (typically thiols) have a certain concentration threshold over which the smell is not perceived significantly stronger; therefore a lower-volatility compound is capable of providing comparable stench intensity to a higher-volatility compound, but for longer time. Another issue is the operating temperature

Operating temperature

An operating temperature is the temperature at which an electrical or mechanical device operates. The device will operate effectively within a specified temperature range which varies based on the device function and application context, and ranges from the minimum operating temperature to the...

, on which the compound's volatility strongly depends. Care should be taken as some compounds are toxic either in higher concentration or after prolonged exposure in low concentration.

Some plants may be used as improvised stink bombs, One such plant is the Parkia speciosa

Parkia speciosa

Parkia speciosa is a plant of the genus Parkia in the family Fabaceae...

 or 'stinky bean', which grows in India

India

India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

, Southeast Asia

Southeast Asia

Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...

 and Eastern Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

. The pods from this plant are collected when partly dried and stamped on, to release the stink.

The most often encountered compounds are:

• Mercaptan
  Thiol
  In organic chemistry, a thiol is an organosulfur compound that contains a carbon-bonded sulfhydryl group...
  
  s
  • Methanethiol
    Methanethiol
    Methanethiol is a colorless gas with a smell like rotten cabbage. It is a natural substance found in the blood and brain of humans and other animal as well as plant tissues. It is disposed of through animal feces. It occurs naturally in certain foods, such as some nuts and cheese...
    
     (used rarely; it is a gas and therefore more difficult to handle than liquids)
  • Ethanethiol
    Ethanethiol
    Ethanethiol is an organic compound with the formula CH3CH2SH. It consists of an ethyl group, CH3CH2, attached to a thiol group, SH. Its structure parallels that of ethanol, but with S instead of O. The presence of S leads to many different properties, most notably the infamous odour of EtSH...
    
    , smelling like deer urine
  • Propanethiol
  • Butanethiol
    Butanethiol
    Butanethiol, also known as butyl mercaptan, is a volatile, clear to yellowish liquid with a fetid odor, commonly described as "skunk" odor. In fact, butanethiol is structurally similar to several major constituents of a skunk's defensive spray...
    
    , skunk
    Skunk
    Skunks are mammals best known for their ability to secrete a liquid with a strong, foul odor. General appearance varies from species to species, from black-and-white to brown or cream colored. Skunks belong to the family Mephitidae and to the order Carnivora...
    
     spray
  • Pentanethiol
• Other sulfur
  Sulfur
  Sulfur or sulphur is the chemical element with atomic number 16. In the periodic table it is represented by the symbol S. It is an abundant, multivalent non-metal. Under normal conditions, sulfur atoms form cyclic octatomic molecules with chemical formula S8. Elemental sulfur is a bright yellow...
  
   compounds
  • Hydrogen sulfide
    Hydrogen sulfide
    Hydrogen sulfide is the chemical compound with the formula . It is a colorless, very poisonous, flammable gas with the characteristic foul odor of expired eggs perceptible at concentrations as low as 0.00047 parts per million...
    
    , smelling of rotten egg
    Egg (food)
    Eggs are laid by females of many different species, including birds, reptiles, amphibians, and fish, and have probably been eaten by mankind for millennia. Bird and reptile eggs consist of a protective eggshell, albumen , and vitellus , contained within various thin membranes...
    
    s
  • Ammonium sulfide
    Ammonium sulfide
    Ammonium hydrosulfide is the chemical compound with the formula SH. It is the salt derived from the ammonium cation and the hydrosulfide anion. The salt exists as colourless, water soluble, micaceous crystals. The compound is encountered mainly as a solution, not as the solid...
    
    , rotten eggs
• Carboxylic acid
  Carboxylic acid
  Carboxylic acids are organic acids characterized by the presence of at least one carboxyl group. The general formula of a carboxylic acid is R-COOH, where R is some monovalent functional group...
  
  s
  • Propionic acid
    Propionic acid
    Propanoic acid is a naturally occurring carboxylic acid with chemical formula CH3CH2COOH. It is a clear liquid with a pungent odor...
    
    , sweat
    SWEAT
    SWEAT is an OLN/TSN show hosted by Julie Zwillich that aired in 2003-2004.Each of the 13 half-hour episodes of SWEAT features a different outdoor sport: kayaking, mountain biking, ice hockey, beach volleyball, soccer, windsurfing, rowing, Ultimate, triathlon, wakeboarding, snowboarding, telemark...
    
    
  • Butyric acid, rancid dairy
  • Valeric acid
  • Caproic acid
    Hexanoic acid
    Hexanoic acid , is the carboxylic acid derived from hexane with the general formula C5H11COOH. It is a colorless oily liquid with an odor that is fatty, cheesy, waxy, and like that of goats or other barnyard animals...
    
    , smelling of cheese
• Aldehyde
  Aldehyde
  An aldehyde is an organic compound containing a formyl group. This functional group, with the structure R-CHO, consists of a carbonyl center bonded to hydrogen and an R group....
  
  s
• Amine
  Amine
  Amines are organic compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are derivatives of ammonia, wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group. Important amines include amino acids, biogenic amines,...
  
  s
  • Ethylamine
    Ethylamine
    Ethylamine is an organic compound with the formula CH3CH2NH2. This colourless gas has a strong ammonia-like odor. It is miscible with virtually all solvents and is considered to be a weak base, as is typical for amines. Ethylamine is widely used in chemical industry and organic...
    
    , fishy smell
  • Putrescine
    Putrescine
    Putrescine is a foul-smelling organic chemical compound NH24NH2 that is related to cadaverine; both are produced by the breakdown of amino acids in living and dead organisms and both are toxic in large doses...
    
    , rotten meat
  • Cadaverine
    Cadaverine
    Cadaverine is a foul-smelling compound produced by protein hydrolysis during putrefaction of animal tissue. Cadaverine is a toxic diamine with the formula NH25NH2, which is similar to putrescine...
    
    , rotten meat
• Heterocyclic compound
  Heterocyclic compound
  A heterocyclic compound is a cyclic compound which has atoms of at least two different elements as members of its ring. The counterparts of heterocyclic compounds are homocyclic compounds, the rings of which are made of a single element....
  
  s
  • Indole
    Indole
    Indole is an aromatic heterocyclic organic compound. It has a bicyclic structure, consisting of a six-membered benzene ring fused to a five-membered nitrogen-containing pyrrole ring. Indole is a popular component of fragrances and the precursor to many pharmaceuticals. Compounds that contain an...
    
    
  • Skatole
    Skatole
    Skatole or 3-methylindole is a mildly toxic white crystalline organic compound belonging to the indole family. It occurs naturally in feces and coal tar, and has a strong fecal odor...
    
    , smelling of feces
    Feces
    Feces, faeces, or fæces is a waste product from an animal's digestive tract expelled through the anus or cloaca during defecation.-Etymology:...
    
    

Standard bathroom malodor

The US Government Standard Bathroom Malodor is quoted to have this composition:

Dipropylene glycol Dipropylene glycol Dipropylene glycol is a mixture of three isomeric chemical compounds, 4-oxa-2,6-heptandiol, 2--propan-1-ol, and 2--propan-1-ol...	62.82%
Skatole Skatole Skatole or 3-methylindole is a mildly toxic white crystalline organic compound belonging to the indole family. It occurs naturally in feces and coal tar, and has a strong fecal odor...	0.91%
2-naphthalenethiol	0.91%
Thioglycolic acid Thioglycolic acid Thioglycolic acid is the organic compound HSCH2CO2H. It contains both a thiol and a carboxylic acid. It is a clear liquid with a strong unpleasant odor...	21.18%
Hexanoic acid Hexanoic acid Hexanoic acid , is the carboxylic acid derived from hexane with the general formula C5H11COOH. It is a colorless oily liquid with an odor that is fatty, cheesy, waxy, and like that of goats or other barnyard animals...	6.00%
p-cresyl isovalerate	2.18%
N-methyl morpholine	6.00%