# Nitrite

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Portmanteau name for nitrite derivatives

Not to be confused with [nitride](/source/Nitride), [nitrate](/source/Nitrate), or [nitrogen dioxide](/source/Nitrogen_dioxide).

Nitrite Names IUPAC name Nitrite Systematic IUPAC name dioxidonitrate(1−) Identifiers CAS Number 14797-65-0 Y 3D model (JSmol) Interactive image ChEBI CHEBI:16301 ChemSpider 921 EC Number 233-272-6 PubChem CID 946 UNII J39976L608 Y InChI InChI=1S/HNO2/c2-1-3/h(H,2,3)/p-1 Key: IOVCWXUNBOPUCH-UHFFFAOYSA-M InChI=1/HNO2/c2-1-3/h(H,2,3)/p-1 Key: IOVCWXUNBOPUCH-REWHXWOFAR SMILES N(=O)[O-] Properties Chemical formula NO−2 Molar mass 46.005 g·mol−1 Conjugate acid Nitrous acid Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Chemical compound

The **nitrite** [ion](/source/Polyatomic_ion) has the [chemical formula](/source/Chemical_formula) NO−2. Nitrite (mostly [sodium nitrite](/source/Sodium_nitrite)) is widely used throughout chemical and pharmaceutical industries.[1] The nitrite anion is a pervasive intermediate in the [nitrogen cycle](/source/Nitrogen_cycle) in nature. The name nitrite also refers to organic compounds having the –ONO group, which are esters of [nitrous acid](/source/Nitrous_acid).

## Production

[Sodium nitrite](/source/Sodium_nitrite) is made industrially by passing a mixture of [nitrogen oxides](/source/Nitrogen_oxide) into aqueous [sodium hydroxide](/source/Sodium_hydroxide) or [sodium carbonate](/source/Sodium_carbonate) solution:[2][1]

- NO + NO2 + 2 NaOH → 2 NaNO2 + H2O

- NO + NO2 + Na2CO3 → 2 NaNO2 + CO2

The product is purified by recrystallization. Alkali metal nitrites are thermally stable up to and beyond their melting point (441 °C (826 °F) for KNO2). [Ammonium nitrite](/source/Ammonium_nitrite) can be made from [dinitrogen trioxide](/source/Dinitrogen_trioxide), N2O3, which is formally the [anhydride](/source/Anhydride) of nitrous acid:

- 2 NH3 + H2O + N2O3 → 2 NH4NO2

## Structure

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The two [canonical structures](/source/Resonance_(chemistry)#Resonance_as_a_diagrammatic_tool) of NO−2, which contribute to the resonance hybrid for the nitrite ion

Dimensions of *trans*-HONO (from the [microwave spectrum](/source/Rotational_spectroscopy))

The nitrite ion has a symmetrical structure (C2v) [symmetry](/source/Molecular_point_group)), with both N–O bonds having equal length and a bond angle of about 115°. In [valence bond theory](/source/Valence_bond_theory), it is described as a [resonance hybrid](/source/Resonance_hybrid) with equal contributions from two canonical forms that are mirror images of each other. In [molecular orbital theory](/source/Molecular_orbital_theory), there is a [sigma bond](/source/Sigma_bond) between each oxygen atom and the nitrogen atom, and a delocalized [pi bond](/source/Pi_bond) made from the [p orbitals](/source/P_orbitals) on nitrogen and oxygen atoms, which is perpendicular to the plane of the molecule. The negative charge of the ion is equally distributed on the two oxygen atoms. Both nitrogen and oxygen atoms carry a [lone pair](/source/Lone_pair) of electrons. Therefore, the nitrite ion is a [Lewis base](/source/Lewis_base).

In the gas phase, it exists predominantly as a *trans*-planar molecule.

## Reactions

### Acid-base properties

Nitrite is the conjugate base of the weak acid [nitrous acid](/source/Nitrous_acid):

- HNO2 ⇌ H+ + NO−2; [p*K*a](/source/Acid_dissociation_constant) ≈ 3.3 at 18 °C (64 °F)[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*]

Nitrous acid is also highly unstable, tending to [disproportionate](/source/Disproportionate):

- 3 HNO2(aq) ⇌ H3O+ + 2 NO + NO−3

This reaction is slow at 0 °C (32 °F).[2] Addition of acid to a solution of a nitrite in the presence of a [reducing agent](/source/Reducing_agent), such as iron(II), is a way to make [nitric oxide](/source/Nitric_oxide) (NO) in the laboratory.

### Oxidation and reduction

The formal [oxidation state](/source/Oxidation_state) of the nitrogen atom in nitrite is +3. This means it can be either oxidized to [oxidation states](/source/Oxidation_state) +4 and +5 or reduced to as low as −3. Standard [reduction potentials](/source/Reduction_potential) for reactions directly involving nitrous acid are shown in the table below:[3]

- Half-reaction E0 (V) NO−3 + 3 H+ + 2 e− ⇌ HNO2 + H2O +0.94 2 HNO2 + 4 H+ + 4 e− ⇌ H2N2O2 + 2 H2O +0.86 N2O4 + 2 H+ + 2 e− ⇌ 2 HNO2 +1.065 2 HNO2 + 4 H+ + 4 e− ⇌ N2O + 3 H2O +1.29

The data can be extended to include products in lower oxidation states. For example:

- H2N2O2 + 2 H+ + 2 e− ⇌ N2 + 2 H2O; *E*0 = +2.65 V

Oxidation reactions usually result in the formation of the [nitrate](/source/Nitrate) ion, with nitrogen in oxidation state +5. For example, oxidation with [permanganate](/source/Permanganate) ion can be used for quantitative analysis of nitrite (by [titration](/source/Titration)):

- 5 NO−2 + 2 MnO−4 + 6 H+ → 2 Mn2+ + 3 H2O + 5 NO−3

The products of reduction reactions with the nitrite ion vary depending on the [reducing agent](/source/Reducing_agent) used and its strength. With [sulfur dioxide](/source/Sulfur_dioxide), the products are NO and N2O; with tin(II) (Sn2+) the product is [hyponitrous acid](/source/Hyponitrous_acid) (H2N2O2); reduction all the way to ammonia (NH3) occurs with [hydrogen sulfide](/source/Hydrogen_sulfide). With the [hydrazinium](/source/Hydrazine) cation (N2H+5) the product of nitrite reduction is [hydrazoic acid](/source/Hydrazoic_acid) (HN3), an unstable and explosive compound:

- N2H+5 + HNO2 → HN3 + H2O + H3O+

which can also further react with nitrite:

- HNO2 + HN3 → N2O + N2 + H2O

This reaction is unusual in that it involves compounds with nitrogen in four different oxidation states.[2]

### Analysis of nitrite

See also: [Nitrite test](/source/Nitrite_test)

Nitrite is detected and analyzed by the [Griess Reaction](/source/Griess_test), involving the formation of a deep red-colored [azo dye](/source/Azo_dye) upon treatment of a NO−2-containing sample with [sulfanilic acid](/source/Sulfanilic_acid) and naphthyl-1-amine in the presence of acid.[4]

### Coordination complexes

Main article: [Transition metal nitrite complex](/source/Transition_metal_nitrite_complex)

Nitrite is an [ambidentate ligand](/source/Ambidentate_ligand) and can form a wide variety of [coordination complexes](/source/Coordination_complex) by binding to metal ions in several ways. For example, the red nitrito pentaamminecobalt complex [Co(NH3)5(ONO)]2+ is [metastable](/source/Metastable), [isomerizing](/source/Isomer) to the yellow [nitro complex \[Co(NH3)5(NO2)\]2+](/source/Nitropentaamminecobalt(III)_chloride).[2]

Nitrite is processed by several enzymes, all of which utilize coordination complexes.[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*]

### Hazardous reactions

When heated with cyanides or thiosulfates, nitrites violently explode.[5]

## Biochemistry

A schematic representation of the microbial nitrogen cycle.[6][7] [ANAMMOX](/source/Anammox) is anaerobic ammonium oxidation, [DNRA](/source/Dissimilatory_nitrate_reduction_to_ammonium) is dissimilatory nitrate reduction to ammonium, and [COMMAMOX](/source/Comammox) is complete ammonium oxidation.

In [nitrification](/source/Nitrification), [ammonium](/source/Ammonium) is converted to nitrite. Important species include *[Nitrosomonas](/source/Nitrosomonas)*. Other bacterial species, such as *[Nitrobacter](/source/Nitrobacter)*, are responsible for oxidizing nitrite to nitrate.[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*]

Nitrite can be reduced to [nitric oxide](/source/Nitric_oxide) or [ammonia](/source/Ammonia) by many species of bacteria. Under hypoxic conditions, nitrite may release nitric oxide, which causes potent [vasodilation](/source/Vasodilation). Several mechanisms for nitrite conversion to NO have been described, including enzymatic reduction by [xanthine oxidoreductase](/source/Xanthine_oxidoreductase), [nitrite reductase](/source/Nitrite_reductase), and [NO synthase](/source/Nitric_oxide_synthase) (NOS), as well as nonenzymatic acidic [disproportionation](/source/Disproportionation) reactions.[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*]

## Uses

### Chemical precursor

[Azo dyes](/source/Azo_dye) and other colorants are prepared by the process called [diazotization](/source/Diazonium_compound#Preparation), which requires nitrite.[1]

### Nitrite in food preservation and biochemistry

This section may lend undue weight to certain ideas, incidents, or controversies. The specific problem is: There are lots of questionable sources mixed in with normal ones being used to push an agenda here, and this much information on food/nutrition aspects probably doesn't belong in what is otherwise a chemistry article about nitrite in the first place. Or, more to the point, since nitrite's dangers in food are well-known at this point in time, why does this section seem like it's trying to convince me from the point of view of a partially deranged vegan? Please help improve it by rewriting it in a balanced fashion that contextualises different points of view. (November 2025) (Learn how and when to remove this message)

See also: [Nitrosamine formation during digestion](/source/Nitrosamine_formation_during_digestion)

The addition of nitrites and nitrates to processed meats such as ham, bacon, and sausages speeds up the [curing](/source/Curing_(food_preservation)) of meat and also imparts an attractive colour. Nitrite reacts with the meat's [myoglobin](/source/Myoglobin) by attaching to the heme iron atom, forming reddish-brown nitrosomyoglobin and the characteristic pink "fresh" color of nitrosohemochrome or nitrosyl-heme upon cooking.[8] [9]

The academic and industrial consensus is that nitrites also reduce the growth and toxin production of *[Clostridium botulinum](/source/Clostridium_botulinum)*.[10][11][12]

On the other hand, a 2018 study by the British Meat Producers Association determined that legally permitted levels of nitrite do not affect the growth of *C. botulinum*.[13]

Addition of [ascorbic acid](/source/Ascorbic_acid), [erythorbic acid](/source/Erythorbic_acid), or one of their salts enhances the binding of nitrite to the iron atom in [myoglobin](/source/Myoglobin).[8] These chemicals also reduce the formation of nitrosamine in the stomach, but only when the fat content of a meal is less than 10%, beyond which they instead increase the formation of nitrosamine.[14][15]

In the U.S., meat cannot be labeled "cured" unless it contains nitrite.[16][17][18] In the US, nitrite has been formally used since 1925. According to scientists working for the industry group [American Meat Institute](/source/American_Meat_Institute), this use of nitrite started in the [Middle Ages](/source/Middle_Ages).[19]

In some countries,[*[which?](https://en.wikipedia.org/wiki/Wikipedia:Avoid_weasel_words)*] cured-meat products are manufactured without [nitrate](/source/Nitrate) or nitrite, and without nitrite from vegetable sources. [Parma ham](/source/Parma_ham), produced without nitrite since 1993, was reported in 2018 to have caused no cases of botulism. This is because the muscle's interior is sterile, while its surface is exposed to oxygen.[9] Other manufacturing processes do not assure these conditions, and reduction of nitrite results in toxin production.[20]

Historians and [epidemiologists](/source/Epidemiology) argue[*[weasel words](https://en.wikipedia.org/wiki/Wikipedia:Avoid_weasel_words)*] that the widespread use of nitrite in meat-curing is closely linked to the development of industrial meat-processing.[21][22] French investigative journalist Guillaume Coudray asserts that the meat industry chooses to cure its meats with nitrite even though it is established that this chemical gives rise to cancer-causing [nitroso](/source/Nitroso)-compounds.[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*] Some traditional and artisanal producers avoid nitrites. As many researchers[*[who?](https://en.wikipedia.org/wiki/Wikipedia:Manual_of_Style/Words_to_watch#Unsupported_attributions)*] nowadays[*[when?](https://en.wikipedia.org/wiki/Wikipedia:Manual_of_Style/Dates_and_numbers#Chronological_items)*] try to point out the hazardous generation of nitrosamines as nitrites bind to free [peptides](/source/Peptide) in the gastrointestinal system, the EU published a regulation that requires lowering nitrite levels in meat curing from 150 to 80 ppm.[23]

In mice, food rich in nitrites together with unsaturated fats can prevent [hypertension](/source/Hypertension) by forming nitro fatty acids that inhibit soluble [epoxide hydrolase](/source/Epoxide_hydrolase), which is one explanation for the apparent health effect of the [Mediterranean diet](/source/Mediterranean_diet).[24] Adding nitrites to meat has been shown to generate known [carcinogens](/source/Carcinogen); the [World Health Organization](/source/World_Health_Organization) (WHO) advises that eating 50 g (1.8 oz) of nitrite processed meat a day would raise the risk of getting [bowel cancer](/source/Bowel_cancer) by 18% over a lifetime.[9]

The recommended maximum limits by the World Health Organization in [drinking water](/source/Drinking_water) are 3 mg/L and 50 mg/L for nitrite and [nitrate](/source/Nitrate) ions, respectively. Ingesting too much nitrite and/or nitrate through well water is suspected to cause [methemoglobinemia](/source/Methemoglobinemia).[25][26]

95% of the nitrite ingested in modern diets comes from bacterial conversion of nitrates naturally found in vegetables.[27] However, potentially cancer-causing nitroso compounds are not formed in the pH-neutral colon. They are mostly produced in the acidic stomach.[28][29]

Since the 1980s, [sorbic acid](/source/Sorbic_acid) and its salts have been used to inhibit *[Clostridium botulinum](/source/Clostridium_botulinum)* in meat products, replacing nitrites to avoid the formation of carcinogenic nitrosamines.[30]

### Antidote for cyanide poisoning

Nitrites in the form of [sodium nitrite](/source/Sodium_nitrite) and [amyl nitrite](/source/Amyl_nitrite) are components of many [cyanide](/source/Cyanide) [antidote](/source/Antidote) kits.[31] Both of these compounds bind to [hemoglobin](/source/Hemoglobin) and oxidize the Fe2+ ions to Fe3+ ions forming [methemoglobin](/source/Methemoglobin). Methemoglobin, in turn, binds to cyanide (CN), creating cyanmethemoglobin, effectively removing cyanide from the [complex IV](/source/Complex_IV) of the [electron transport chain](/source/Electron_transport_chain) (ETC) in [mitochondria](/source/Mitochondrion), which is the primary site of disruption caused by cyanide. Another mechanism by which nitrites help treat cyanide toxicity is the generation of [nitric oxide](/source/Nitric_oxide) (NO). NO displaces the CN from the [cytochrome c oxidase](/source/Cytochrome_c_oxidase) (ETC complex IV), making it available for methemoglobin to bind.[32]

## Organic nitrites

A nitrite ester

In [organic chemistry](/source/Organic_chemistry), [alkyl nitrites](/source/Alkyl_nitrites) are [esters](/source/Ester) of nitrous acid and contain the nitrosoxy functional group. Nitro compounds contain the C−NO2 group. Nitrites have the general formula RONO, where R is an [aryl](/source/Aryl) or [alkyl](/source/Alkyl) group. [Amyl nitrite](/source/Amyl_nitrite) and other alkyl nitrites have a [vasodilating action](/source/Vasodilation) and must be handled in the laboratory with caution. They are sometimes used in medicine to treat heart disease. A classic [named reaction](/source/Named_reaction) for the synthesis of alkyl nitrites is the [Meyer synthesis](/source/Meyer_synthesis) in which [alkyl halides](/source/Alkyl_halide) react with metallic nitrites to a mixture of nitroalkanes and nitrites.[33][34]

## Safety

See also: [Curing (food preservation) § Nitrates and nitrites](/source/Curing_(food_preservation)#Nitrates_and_nitrites)

Large doses of nitrites cause acute poisoning in the form of [methemoglobinemia](/source/Methemoglobinemia), which can lead to death.[35]

## See also

- [Curing (food preservation)](/source/Curing_(food_preservation))

- [Alkyl nitrites](/source/Alkyl_nitrites)

## References

1. ^ [***a***](#cite_ref-Ullmann_1-0) [***b***](#cite_ref-Ullmann_1-1) [***c***](#cite_ref-Ullmann_1-2) Laue, Wolfgang; Thiemann, Michael; Scheibler, Erich; Wiegand, Karl Wilhelm (2006). "Nitrates and Nitrites". *[Ullmann's Encyclopedia of Industrial Chemistry](/source/Ullmann's_Encyclopedia_of_Industrial_Chemistry)*. Weinheim: Wiley-VCH. [doi](/source/Doi_(identifier)):[10.1002/14356007.a17_265](https://doi.org/10.1002%2F14356007.a17_265). [ISBN](/source/ISBN_(identifier)) [978-3-527-30673-2](https://en.wikipedia.org/wiki/Special:BookSources/978-3-527-30673-2).

1. ^ [***a***](#cite_ref-p461_2-0) [***b***](#cite_ref-p461_2-1) [***c***](#cite_ref-p461_2-2) [***d***](#cite_ref-p461_2-3) [Greenwood, Norman N.](/source/Norman_Greenwood); Earnshaw, Alan (1997). *Chemistry of the Elements* (2nd ed.). Butterworth-Heinemann. pp. 461–464. [doi](/source/Doi_(identifier)):[10.1016/C2009-0-30414-6](https://doi.org/10.1016%2FC2009-0-30414-6). [ISBN](/source/ISBN_(identifier)) [978-0-08-037941-8](https://en.wikipedia.org/wiki/Special:BookSources/978-0-08-037941-8).

1. **[^](#cite_ref-3)** [Greenwood, Norman N.](/source/Norman_Greenwood); Earnshaw, Alan (1997). *Chemistry of the Elements* (2nd ed.). Butterworth-Heinemann. p. 431. [doi](/source/Doi_(identifier)):[10.1016/C2009-0-30414-6](https://doi.org/10.1016%2FC2009-0-30414-6). [ISBN](/source/ISBN_(identifier)) [978-0-08-037941-8](https://en.wikipedia.org/wiki/Special:BookSources/978-0-08-037941-8).

1. **[^](#cite_ref-4)** Ivanov, V. M. (1 October 2004). "The 125th Anniversary of the Griess Reagent". *Journal of Analytical Chemistry*. **59** (10): 1002–1005. [doi](/source/Doi_(identifier)):[10.1023/B:JANC.0000043920.77446.d7](https://doi.org/10.1023%2FB%3AJANC.0000043920.77446.d7). [ISSN](/source/ISSN_(identifier)) [1608-3199](https://search.worldcat.org/issn/1608-3199). [S2CID](/source/S2CID_(identifier)) [98768756](https://api.semanticscholar.org/CorpusID:98768756).

1. **[^](#cite_ref-5)** Kaye, Seymour M. (1 January 1978). "N – Nitrites". [*Encyclopedia of Explosives and Related Items*](https://apps.dtic.mil/sti/pdfs/ADA057762.pdf#page=292) (PDF) (Technical report). Vol. 8, M1 Thickener through Pyruvonitrolic Acid. Dover, NJ: Army Armament Research And Development Center – Large Caliber Weapon Systems Lab. p. N107. [LCCN](/source/LCCN_(identifier)) [61-61759](https://lccn.loc.gov/61-61759). ADA057762, PATR 2700.

1. **[^](#cite_ref-6)** Sparacino-Watkins, Courtney; Stolz, John F.; Basu, Partha (16 December 2013). ["Nitrate and periplasmic nitrate reductases"](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4080430). *Chem. Soc. Rev*. **43** (2): 676–706. [doi](/source/Doi_(identifier)):[10.1039/c3cs60249d](https://doi.org/10.1039%2Fc3cs60249d). [ISSN](/source/ISSN_(identifier)) [1460-4744](https://search.worldcat.org/issn/1460-4744). [PMC](/source/PMC_(identifier)) [4080430](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4080430). [PMID](/source/PMID_(identifier)) [24141308](https://pubmed.ncbi.nlm.nih.gov/24141308).

1. **[^](#cite_ref-7)** Simon, Jörg; Klotz, Martin G. (2013). ["Diversity and evolution of bioenergetic systems involved in microbial nitrogen compound transformations"](https://doi.org/10.1016%2Fj.bbabio.2012.07.005). *Biochimica et Biophysica Acta (BBA) - Bioenergetics*. **1827** (2): 114–135. [doi](/source/Doi_(identifier)):[10.1016/j.bbabio.2012.07.005](https://doi.org/10.1016%2Fj.bbabio.2012.07.005). [PMID](/source/PMID_(identifier)) [22842521](https://pubmed.ncbi.nlm.nih.gov/22842521).

1. ^ [***a***](#cite_ref-ind_8-0) [***b***](#cite_ref-ind_8-1) Pappenberger, Günter; Hohmann, Hans-Peter (2013). "Industrial Production of L-Ascorbic Acid (Vitamin C) and D-Isoascorbic Acid". *Biotechnology of Food and Feed Additives*. Advances in Biochemical Engineering/Biotechnology. **143**: 143–188. [doi](/source/Doi_(identifier)):[10.1007/10_2013_243](https://doi.org/10.1007%2F10_2013_243). [ISBN](/source/ISBN_(identifier)) [978-3-662-43760-5](https://en.wikipedia.org/wiki/Special:BookSources/978-3-662-43760-5). [PMID](/source/PMID_(identifier)) [24258144](https://pubmed.ncbi.nlm.nih.gov/24258144).

1. ^ [***a***](#cite_ref-Wilson_9-0) [***b***](#cite_ref-Wilson_9-1) [***c***](#cite_ref-Wilson_9-2) Wilson, Bee (1 March 2018). ["Yes, bacon really is killing us"](https://www.theguardian.com/news/2018/mar/01/bacon-cancer-processed-meats-nitrates-nitrites-sausages). *The Guardian*. London. [ISSN](/source/ISSN_(identifier)) [0261-3077](https://search.worldcat.org/issn/0261-3077). [Archived](https://web.archive.org/web/20210210183650/https://www.theguardian.com/news/2018/mar/01/bacon-cancer-processed-meats-nitrates-nitrites-sausages) from the original on 10 February 2021. Retrieved 14 February 2021. In trade journals of the 1960s, the firms who sold nitrite powders to ham-makers spoke quite openly about how the main advantage was to increase profit margins by speeding up production.

1. **[^](#cite_ref-10)** Christiansen LN, Johnston RW, Kautter DA, Howard JW, Aunan WJ (March 1973). ["Effect of nitrite and nitrate on toxin production by Clostridium botulinum and on nitrosamine formation in perishable canned comminuted cured meat"](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC380811). *Applied Microbiology*. **25** (3): 357–362. [doi](/source/Doi_(identifier)):[10.1128/AEM.25.3.357-362.1973](https://doi.org/10.1128%2FAEM.25.3.357-362.1973). [PMC](/source/PMC_(identifier)) [380811](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC380811). [PMID](/source/PMID_(identifier)) [4572891](https://pubmed.ncbi.nlm.nih.gov/4572891).

1. **[^](#cite_ref-11)** Lee, Soomin; Lee, Heeyoung; Kim, Sejeong; Lee, Jeeyeon; Ha, Jimyeong; Choi, Yukyung; Oh, Hyemin; Choi, Kyoung-Hee; Yoon, Yohan (August 2018). ["Microbiological safety of processed meat products formulated with low nitrite concentration — A review"](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6043430). *Asian-Australasian Journal of Animal Sciences*. **31** (8): 1073–1077. [doi](/source/Doi_(identifier)):[10.5713/ajas.17.0675](https://doi.org/10.5713%2Fajas.17.0675). [ISSN](/source/ISSN_(identifier)) [1011-2367](https://search.worldcat.org/issn/1011-2367). [PMC](/source/PMC_(identifier)) [6043430](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6043430). [PMID](/source/PMID_(identifier)) [29531192](https://pubmed.ncbi.nlm.nih.gov/29531192).

1. **[^](#cite_ref-12)** Sindelar, Jeffrey J.; Milkowski, Andrew L. (May 2012). "Human safety controversies surrounding nitrate and nitrite in the diet". *Nitric Oxide*. **26** (4): 259–266. [doi](/source/Doi_(identifier)):[10.1016/j.niox.2012.03.011](https://doi.org/10.1016%2Fj.niox.2012.03.011). [PMID](/source/PMID_(identifier)) [22487433](https://pubmed.ncbi.nlm.nih.gov/22487433).

1. **[^](#cite_ref-13)** Doward, Jamie (23 March 2019). ["Revealed: no need to add cancer-risk nitrites to ham"](https://www.theguardian.com/food/2019/mar/23/nitrites-ham-bacon-cancer-risk-additives-meat-industry-confidential--report). *The Observer*. London. [Archived](https://web.archive.org/web/20210126134441/https://www.theguardian.com/food/2019/mar/23/nitrites-ham-bacon-cancer-risk-additives-meat-industry-confidential--report) from the original on 26 January 2021. Retrieved 14 February 2021. The results show that there is no change in levels of inoculated *C. botulinum* over the curing process, which implies that the action of nitrite during curing is not toxic to *C. botulinum* spores at levels of 150ppm [parts per million] ingoing nitrite and below.

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1. **[^](#cite_ref-24)** Charles, R. L.; Rudyk, O.; Prysyazhna, O.; Kamynina, A.; Yang, J.; Morisseau, C.; Hammock, B. D.; Freeman, B. A.; Eaton, P. (2014). ["Protection from hypertension in mice by the Mediterranean diet is mediated by nitro fatty acid inhibition of soluble epoxide hydrolase"](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4050620). *Proceedings of the National Academy of Sciences*. **111** (22): 8167–8172. [Bibcode](/source/Bibcode_(identifier)):[2014PNAS..111.8167C](https://ui.adsabs.harvard.edu/abs/2014PNAS..111.8167C). [doi](/source/Doi_(identifier)):[10.1073/pnas.1402965111](https://doi.org/10.1073%2Fpnas.1402965111). [PMC](/source/PMC_(identifier)) [4050620](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4050620). [PMID](/source/PMID_(identifier)) [24843165](https://pubmed.ncbi.nlm.nih.gov/24843165).

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1. **[^](#cite_ref-28)** Lee, L; Archer, MC; Bruce, WR (October 1981). "Absence of volatile nitrosamines in human feces". *Cancer Res*. **41** (10): 3992–3994. [PMID](/source/PMID_(identifier)) [7285009](https://pubmed.ncbi.nlm.nih.gov/7285009).

1. **[^](#cite_ref-29)** Kuhnle, GG; Story, GW; Reda, T; et al. (October 2007). "Diet-induced endogenous formation of nitroso compounds in the GI tract". *Free Radic. Biol. Med*. **43** (7): 1040–1047. [doi](/source/Doi_(identifier)):[10.1016/j.freeradbiomed.2007.03.011](https://doi.org/10.1016%2Fj.freeradbiomed.2007.03.011). [PMID](/source/PMID_(identifier)) [17761300](https://pubmed.ncbi.nlm.nih.gov/17761300).

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1. **[^](#cite_ref-31)** Meillier, Andrew; Heller, Cara (2015). ["Acute Cyanide Poisoning: Hydroxocobalamin and Sodium Thiosulfate Treatments with Two Outcomes following One Exposure Event"](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4620268). *Case Reports in Medicine*. **2015** 217951. [doi](/source/Doi_(identifier)):[10.1155/2015/217951](https://doi.org/10.1155%2F2015%2F217951). [ISSN](/source/ISSN_(identifier)) [1687-9627](https://search.worldcat.org/issn/1687-9627). [PMC](/source/PMC_(identifier)) [4620268](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4620268). [PMID](/source/PMID_(identifier)) [26543483](https://pubmed.ncbi.nlm.nih.gov/26543483).

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## External links

Wikimedia Commons has media related to [Nitrites](https://commons.wikimedia.org/wiki/Category:Nitrites).

v t e Nitrogen species Hydrides NH3 NH+4 NH−2 N3− NH2OH N2H4 HN3 N−3 NH5 (?) Organic NR3 >C=NR −CONR2 −CN HCN CN− (CN)2 H2NCN HOCN HNCO HNCS CH2N2 −NO −NO2 Oxides NO / (NO)2 N2O3 HNO2 / NO−2 / NO+ NO2 / (NO2)2 N2O5 HNO3 / NO−3 / NO+2 NO3 HNO / (HON)2 / N2O2−2 / N2O H2NNO2 HO2NO / ONOO− HO2NO2 / O2NOO− NO3−4 H4N2O4 / N2O2−3 Halides NF NF2 NF3 NF5 (?) NCl3 NBr3 NI3 FN3 ClN3 BrN3 IN3 NH2F N2F2 NH2Cl NHF2 NHCl2 NHBr2 NHI2 NClF2 Oxidation states −3, −2, −1, 0, +1, +2, +3, +4, +5 (a strongly acidic oxide)

v t e Salts and covalent derivatives of the nitrite ion HNO2 He LiNO2 Be(NO2)2 B C(NO2)4 CH(NO2)3 CH2(NO2)2 CH3(NO2) HNO2 N(NO2)3 H2NNO2 –NO3, –NO2 N2O3 NO2F Ne NaNO2 Mg(NO2)2 Al(NO2)3 Si P S NO2Cl Ar KNO2 Ca(NO2)2 Sc(NO2)3 Ti VO(NO2)3 Cr(NO2)3 Mn(NO2)2 Fe(NO2)3 Co(NO2)2 Co(NO2)3 Ni(NO2)2 Cu(NO2)2 Zn(NO2)2 Ga(NO2)3 Ge As Se NO2Br Kr RbNO2 Sr(NO2)2 Y(NO2)3 Zr Nb Mo Tc Ru Rh Pd(NO2)2 AgNO2 Cd(NO2)2 In Sn Sb Te NO2I Xe CsNO2 Ba(NO2)2 * Lu Hf Ta W Re Os Ir Pt(NO2)2 [Pt(NO2)4]2− Au Hg2(NO2)2 Hg(NO2)2 TlNO2 Pb(NO2)2 Bi(NO2)3 BiO(NO2) Po At Rn Fr Ra ** Lr Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og * La(NO2)3 Ce(NO2)3 Pr(NO2)3 Nd(NO2)3 Pm Sm(NO2)3 Eu(NO2)2 Gd(NO2)3 Tb Dy Ho Er Tm Yb ** Ac Th Pa UO2(NO2)2 Np Pu Am Cm Bk Cf Es Fm Md No

v t e Nitric oxide signaling modulators Forms Nitroxyl anion (NO−; oxonitrate(1-), hyponitrite anion) Nitric oxide (NO⋅; nitrogen monoxide) Nitrosonium (NO+; nitrosyl cation) Targets sGC Activators/stimulators: Ataciguat Avenciguat BAY 41-2272 BAY 41-8543 BAY 60-4552 BI-703704 Cinaciguat (BAY 58-2667) CY-3018 Frespaciguat GSK-2181236A Olinciguat Praliciguat Riociguat Vericiguat Zagociguat Inhibitors: ODQ NO donors (prodrugs) Nitrates: Diethylene glycol dinitrate (DEGDN) Erythritol tetranitrate (ETN) Ethylene glycol dinitrate (EGDN; nitroglycol) Isosorbide mononitrate (ISMN) Isosorbide dinitrate (ISDN) Itramin tosilate Mannitol hexanitrate Naproxcinod (nitronaproxen; AZD-3582, HCT-3012) NCX-466 NCX-2216 NCX-4016 NCX 4040 NCX-4215 Nicorandil Nipradilol (K-351) Nitrate (NO− 3) Nitroatorvastatin (NCX-6560) Nitroflurbiprofen (HCT-1026) Nitrofluvastatin Nitroglycerin (glyceryl trinitrate (GTN)) Nitropravastatin (NCX-6550) Pentaerithrityl tetranitrate (PETN) Propatylnitrate Propylene glycol dinitrate (PGDN) Sodium trioxodinitrate (Angeli's salt) Tenitramine Trolnitrate Nitroso compounds/nitrites: Nitrite (NO− 2); O-Nitroso compounds (alkyl nitrites): Amyl nitrite (isoamyl nitrite, isopentyl nitrite) Cyclohexyl nitrite Ethyl nitrite Hexyl nitrite Isobutyl nitrite (2-methylpropyl nitrite) Isopropyl nitrite Methyl nitrite n-Butyl nitrite Pentyl nitrite tert-Butyl nitrite; S-Nitroso compounds (thionitrites): LA810 S-Nitrosoalbumin (SNALB) S-Nitrosated AR545C S-Nitroso-N-acetylcysteine (SNAC) S-Nitroso-N-acetylpenicillamine (SNAP) S-Nitroso-N-valerylpenicillamine (SNVP) S-Nitrosocaptopril (SNO-Cap) S-Nitrosocysteine (SNC, CysNO, SNO-Cys) S-Nitrosodiclofenac S-Nitrosoglutathione (GSNO, SNOG) SNO-t-PA SNO-vWF; N-Nitroso compounds (e.g., nitrosamines): SIN-1A Nitrosyl compounds: Metal nitrosyl complexes: Roussin's black salt Roussin's red salt Sodium nitroprusside (SNP) NONOates (diazeniumdiolates): Diethylamine/NO (DEA/NO) Diethylenetriamine/NO (DETA/NO) GLO/NO JS-K Methylamine hexamethylene methylamine/NO (MAHMA/NO) PROLI/NO Spermine/NO (SPER/NO) V-PYRRO/NO Heterocyclic compounds: Furoxans: Furoxan REC15/2739; Sydnonimines: Feprosidnine Linsidomine (SIN-1) Molsidomine (SIN-10) Sydnonimine Unsorted: Cimlanod FK-409 FR144220 FR146881 N-Acetyl-N-acetoxy-4-chlorobenzenesulfonamide Enzyme (inhibitors) NOS nNOS 3-Bromo-7-nitroindazole 3-Chloroindazole 3-Chloro-5-nitroindazole 5-Nitroindazole 6-Nitroindazole 7-Nitroindazole A-84643 Aminoguanidine (pimagedine) ARL-17477 Indazole N5-(1-Iminoethyl)-L-ornithine (L-NIO) Nω-Methyl-L-arginine (L-NMA) Nω-Propyl-L-arginine (L-NPA) Nitroarginine (NNA, NOARG) Pentamidine isethionate TRIM iNOS 1-Amino-2-hydroxyguanidine 2-Ethylaminoguanidine 2-Iminopiperidine 1400W AEITU Aminoguanidine (pimagedine) AMT AR-C 102222 BYK-191023 Canavanine Cindunistat (SD-6010) EITU IPTU MITU N5-(1-Iminoethyl)-L-ornithine (L-NIO) N6-(1-Iminoethyl)-L-lysine (L-NIL) Nω-Methyl-L-arginine (L-NMA) Ronopterin (VAS-203) TRIM eNOS Aminoguanidine (pimagedine) N5-(1-Iminoethyl)-L-ornithine (L-NIO) Nω-Methyl-L-arginine (L-NMA) Nitroarginine (NNA, NOARG) Unsorted Asymmetric dimethylarginine (ADMA) CKD-712 Guanidinoethyldisulfide (GED) GW-273629 Indospicine KD-7040 Nitroarginine methyl ester (NAME) NCX-456 NXN-462 ONO-1714 VAS-2381 Arginase ABH Nω-Hydroxy-L-arginine (NOHA) chlorogenic acid ginseng epicatechin ornithine norvaline lysine alpha aminoacids CAMK Calmidazolium W-7 Others Precursors: L-Arginine Nω-Hydroxy-L-arginine (NOHA) Cofactors: NADPH FAD FMN Heme BH4 CaM O2 Ca2+ Indirect/downstream NO modulators: ACE inhibitors/AT-II receptor antagonists (e.g., captopril, losartan) ETB receptor antagonists (e.g., bosentan) L-Type calcium channel blockers (e.g., dihydropyridines: nifedipine) Nebivolol (beta blocker) PDE5 inhibitors (e.g., sildenafil) non-selective PDE inhibitors (e.g., caffeine) PDE9 inhibitors (e.g., paraxanthine) cGMP preferring PDE inhibitors (e.g., sildenafil, paraxanthine, tadalafil) Statins (e.g., simvastatin) See also: Receptor/signaling modulators

Authority control databases: National Czech Republic Israel

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