Nitrite

Last updated

Contents

Nitrite
Nitrit-Ion2.svg
Nitrite-3D-vdW.png
Names
IUPAC name
Nitrite
Systematic IUPAC name
dioxidonitrate(1−)
Other names
nitrite
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
EC Number
  • 233-272-6
PubChem CID
UNII
  • 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
  • N(=O)[O-]
Properties
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).

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

Production

Sodium nitrite is made industrially by passing a mixture of nitrogen oxides into aqueous sodium hydroxide or 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 for KNO2). Ammonium nitrite can be made from dinitrogen trioxide, N2O3, which is formally the anhydride of nitrous acid:

2 NH3 + H2O + N2O3 → 2 NH4NO2

Structure

The two canonical structures of NO
2, which contribute to the resonance hybrid for the nitrite ion Nitrite-ion-canonical-structures.svg
The two canonical structures of NO
2
, which contribute to the resonance hybrid for the nitrite ion
Dimensions of trans-HONO (from the microwave spectrum) Trans-nitrous-acid-2D-dimensions.png
Dimensions of trans-HONO (from the microwave spectrum)

The nitrite ion has a symmetrical structure (C2v symmetry), with both N–O bonds having equal length and a bond angle of about 115°. In valence bond theory, it is described as a resonance hybrid with equal contributions from two canonical forms that are mirror images of each other. In molecular orbital theory, there is a sigma bond between each oxygen atom and the nitrogen atom, and a delocalized pi bond made from the 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 of electrons. Therefore, the nitrite ion is a 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:

HNO2 H+ + NO
2
;      pKa ≈ 3.3 at 18 °C [3]

Nitrous acid is also highly volatile, tending to disproportionate:

3 HNO2 (aq) H3O+ + NO
3
+ 2 NO

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

Oxidation and reduction

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

Half-reactionE0 (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;     E0 = +2.65 V

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

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

The product of reduction reactions with nitrite ion are varied, depending on the reducing agent used and its strength. With sulfur dioxide, the products are NO and N2O; with tin(II) (Sn2+) the product is hyponitrous acid (H2N2O2); reduction all the way to ammonia (NH3) occurs with hydrogen sulfide. With the hydrazinium cation (N
2
H+
5
) the product of nitrite reduction is hydrazoic acid (HN3), an instable and explosive compound:

HNO2 + N
2
H+
5
→ 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

Nitrite is detected and analyzed by the Griess Reaction, involving the formation of a deep red-colored azo dye upon treatment of a NO
2
-containing sample with sulfanilic acid and naphthyl-1-amine in the presence of acid. [5]

Coordination complexes

Nitrite is an ambidentate ligand and can form a wide variety of coordination complexes by binding to metal ions in several ways. [2] Two examples are the red nitrito complex [Co(NH3)5(ONO)]2+ is metastable, isomerizing to the yellow nitro complex [Co(NH3)5(NO2)]2+. Nitrite is processed by several enzymes, all of which utilize coordination complexes.

Biochemistry

A schematic representation of the microbial nitrogen cycle. ANAMMOX is anaerobic ammonium oxidation, DNRA is dissimilatory nitrate reduction to ammonium, and COMMAMOX is complete ammonium oxidation. Nitrogen Cycle - Reactions and Enzymes.svg
A schematic representation of the microbial nitrogen cycle. ANAMMOX is anaerobic ammonium oxidation, DNRA is dissimilatory nitrate reduction to ammonium, and COMMAMOX is complete ammonium oxidation.

In nitrification, ammonium is converted to nitrite. Important species include Nitrosomonas . Other bacterial species such as Nitrobacter , are responsible for the oxidation of the nitrite into nitrate.

Nitrite can be reduced to nitric oxide or ammonia by many species of bacteria. Under hypoxic conditions, nitrite may release nitric oxide, which causes potent vasodilation. Several mechanisms for nitrite conversion to NO have been described, including enzymatic reduction by xanthine oxidoreductase, nitrite reductase, and NO synthase (NOS), as well as nonenzymatic acidic disproportionation reactions.

Uses

Chemical precursor

Azo dyes and other colorants are prepared by the process called diazotization, which requires nitrite. [1]

Nitrite in food preservation and biochemistry

The addition of nitrites and nitrates to processed meats such as ham, bacon, and sausages reduces growth and toxin production of C. botulinum. [8] [9] Sodium nitrite is used to speed up the curing of meat and also impart an attractive colour. [10] 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 the Clostridium botulinum . [11] In the U.S., meat cannot be labeled as "cured" without the addition of nitrite. [12] [13] [14] In some countries, cured-meat products are manufactured without nitrate or nitrite, and without nitrite from vegetable source. Parma ham, produced without nitrite since 1993, was reported in 2018 to have caused no cases of botulism. [10]

In mice, food rich in nitrites together with unsaturated fats can prevent hypertension, which is one explanation for the apparent health effect of the Mediterranean diet. [15] Adding nitrites to meat has been shown to generate known carcinogens; the 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 by 18% over a lifetime. [10] However, 95% of the nitrite ingested in modern diets comes from bacterial conversion of nitrates naturally found in dietary vegetables. [16]

The recommended maximum limits by the World Health Organization in drinking water are 3 mg L−1 and 50 mg L−1 for nitrite and nitrate ions, respectively. [17]

Curing of meat

In a reaction with the meat's myoglobin, nitrite gives the product a desirable pink-red "fresh" color, such as with corned beef. In the US, nitrite has been formally used since 1925. According to scientists working for the industry group American Meat Institute, this use of nitrite started in the Middle Ages. [18] Historians and epidemiologists argue that the widespread use of nitrite in meat-curing is closely linked to the development of industrial meat-processing. [19] [20] French investigative journalist Guillaume Coudray  [ fr ] 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-compounds. [21] Some traditional and artisanal producers avoid nitrites.

Antidote for cyanide poisoning

Nitrites in the form of sodium nitrite and amyl nitrite are components of many cyanide antidote kits. [22] Both of these compounds bind to hemoglobin and oxidize the Fe2+ ions to Fe3+ ions forming methemoglobin. Methemoglobin, in turn, binds to cyanide (CN), creating cyanmethemoglobin, effectively removing cyanide from the complex IV of the electron transport chain (ETC) in mitochondria, 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 (NO). NO displaces the CN from the cytochrome c oxidase (ETC complex IV), making it available for methemoglobin to bind. [23]

Organic nitrites

A nitrite ester Nitrite-group-2D.svg
A nitrite ester

In organic chemistry, alkyl nitrites are esters 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 or alkyl group. Amyl nitrite and other alkyl nitrites have a vasodilating action and must be handled in the laboratory with caution. They are sometimes used in medicine for the treatment of heart diseases. A classic named reaction for the synthesis of alkyl nitrites is the Meyer synthesis [24] [25] in which alkyl halides react with metallic nitrites to a mixture to nitroalkanes and nitrites.

Safety

Nitrite salts can react with secondary amines to produce N-nitrosamines, which are suspected of causing stomach cancer. The World Health Organization (WHO) advises that each 50 g (1.8 oz) of processed meat eaten a day would raise the risk of getting bowel cancer by 18% over a lifetime; processed meat refers to meat that has been transformed through fermentation, nitrite curing, salting, smoking, or other processes to enhance flavor or improve preservation. The World Health Organization's review of more than 400 studies concluded in 2015 that there was sufficient evidence that processed meats caused cancer, particularly colon cancer; the WHO's International Agency for Research on Cancer (IARC) classified processed meats as carcinogenic to humans (Group 1). [10] [26]

Nitrite (ingested) under conditions that result in endogenous nitrosation, specifically the production of nitrosamine, has been classified as Probably carcinogenic to humans (Group 2A) by the IARC. [27]

See also

Related Research Articles

<span class="mw-page-title-main">Nitrogen</span> Chemical element with atomic number 7 (N)

Nitrogen is a chemical element; it has symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at seventh in total abundance in the Milky Way and the Solar System. At standard temperature and pressure, two atoms of the element bond to form N2, a colourless and odourless diatomic gas. N2 forms about 78% of Earth's atmosphere, making it the most abundant chemical species in air. Because of the volatility of nitrogen compounds, nitrogen is relatively rare in the solid parts of the Earth.

<span class="mw-page-title-main">Nitrate</span> Polyatomic ion (NO₃, charge –1) found in explosives and fertilisers

Nitrate is a polyatomic ion with the chemical formula NO
3
. Salts containing this ion are called nitrates. Nitrates are common components of fertilizers and explosives. Almost all inorganic nitrates are soluble in water. An example of an insoluble nitrate is bismuth oxynitrate.

<span class="mw-page-title-main">Dinitrogen tetroxide</span> Chemical compound

Dinitrogen tetroxide, commonly referred to as nitrogen tetroxide (NTO), and occasionally (usually among ex-USSR/Russian rocket engineers) as amyl, is the chemical compound N2O4. It is a useful reagent in chemical synthesis. It forms an equilibrium mixture with nitrogen dioxide. Its molar mass is 92.011 g/mol.

<span class="mw-page-title-main">Nitric oxide</span> Colorless gas with the formula NO

Nitric oxide is a colorless gas with the formula NO. It is one of the principal oxides of nitrogen. Nitric oxide is a free radical: it has an unpaired electron, which is sometimes denoted by a dot in its chemical formula. Nitric oxide is also a heteronuclear diatomic molecule, a class of molecules whose study spawned early modern theories of chemical bonding.

<span class="mw-page-title-main">Nitrogen dioxide</span> Chemical compound with formula NO₂

Nitrogen dioxide is a chemical compound with the formula NO2. One of several nitrogen oxides, nitrogen dioxide is a reddish-brown gas. It is a paramagnetic, bent molecule with C2v point group symmetry. Industrially, NO2 is an intermediate in the synthesis of nitric acid, millions of tons of which are produced each year, primarily for the production of fertilizers.

In chemistry, azide is a linear, polyatomic anion with the formula N−3 and structure N=N+=N. It is the conjugate base of hydrazoic acid HN3. Organic azides are organic compounds with the formula RN3, containing the azide functional group. The dominant application of azides is as a propellant in air bags.

<span class="mw-page-title-main">Nitrous acid</span> Chemical compound

Nitrous acid is a weak and monoprotic acid known only in solution, in the gas phase, and in the form of nitrite salts. It was discovered by Carl Wilhelm Scheele, who called it "phlogisticated acid of niter". Nitrous acid is used to make diazonium salts from amines. The resulting diazonium salts are reagents in azo coupling reactions to give azo dyes.

<span class="mw-page-title-main">Sodium nitrite</span> Chemical compound

Sodium nitrite is an inorganic compound with the chemical formula NaNO2. It is a white to slightly yellowish crystalline powder that is very soluble in water and is hygroscopic. From an industrial perspective, it is the most important nitrite salt. It is a precursor to a variety of organic compounds, such as pharmaceuticals, dyes, and pesticides, but it is probably best known as a food additive used in processed meats and in fish products.

<span class="mw-page-title-main">Nitro compound</span> Organic compound containing an −NO₂ group

In organic chemistry, nitro compounds are organic compounds that contain one or more nitro functional groups. The nitro group is one of the most common explosophores used globally. The nitro group is also strongly electron-withdrawing. Because of this property, C−H bonds alpha (adjacent) to the nitro group can be acidic. For similar reasons, the presence of nitro groups in aromatic compounds retards electrophilic aromatic substitution but facilitates nucleophilic aromatic substitution. Nitro groups are rarely found in nature. They are almost invariably produced by nitration reactions starting with nitric acid.

<span class="mw-page-title-main">Sodium azide</span> Chemical compound

Sodium azide is an inorganic compound with the formula NaN3. This colorless salt is the gas-forming component in some car airbag systems. It is used for the preparation of other azide compounds. It is an ionic substance, is highly soluble in water, and is acutely poisonous.

<span class="mw-page-title-main">Sulfamic acid</span> Chemical compound

Sulfamic acid, also known as amidosulfonic acid, amidosulfuric acid, aminosulfonic acid, sulphamic acid and sulfamidic acid, is a molecular compound with the formula H3NSO3. This colourless, water-soluble compound finds many applications. Sulfamic acid melts at 205 °C before decomposing at higher temperatures to water, sulfur trioxide, sulfur dioxide and nitrogen.

<span class="mw-page-title-main">Nitrosation and nitrosylation</span> Process of converting organic compounds into nitroso derivatives

Nitrosation and nitrosylation are two names for the process of converting organic compounds or metal complexes into nitroso derivatives, i.e., compounds containing the R−NO functionality. The synonymy arises because the R-NO functionality can be interpreted two different ways, depending on the physico-chemical environment:

<span class="mw-page-title-main">Potassium nitrite</span> Chemical compound

Potassium nitrite (distinct from potassium nitrate) is the inorganic compound with the chemical formula KNO2. It is an ionic salt of potassium ions K+ and nitrite ions NO2, which forms a white or slightly yellow, hygroscopic crystalline powder that is soluble in water.

The nitrosonium ion is NO+, in which the nitrogen atom is bonded to an oxygen atom with a bond order of 3, and the overall diatomic species bears a positive charge. It can be viewed as nitric oxide with one electron removed. This ion is usually obtained as the following salts: NOClO4, NOSO4H (nitrosylsulfuric acid, more descriptively written ONSO3OH) and NOBF4. The ClO−4 and BF−4 salts are slightly soluble in acetonitrile CH3CN. NOBF4 can be purified by sublimation at 200–250 °C and 0.01 mmHg (1.3 Pa).

The chemical element nitrogen is one of the most abundant elements in the universe and can form many compounds. It can take several oxidation states; but the most common oxidation states are -3 and +3. Nitrogen can form nitride and nitrate ions. It also forms a part of nitric acid and nitrate salts. Nitrogen compounds also have an important role in organic chemistry, as nitrogen is part of proteins, amino acids and adenosine triphosphate.

<span class="mw-page-title-main">Curing salt</span> Salt used in food preservation

Curing salt is used in meat processing to generate a pinkish shade and to extend shelf life. It is both a color agent and a means to facilitate food preservation as it prevents or slows spoilage by bacteria or fungus. Curing salts are generally a mixture of sodium chloride and sodium nitrite, and are used for pickling meats as part of the process to make sausage or cured meat such as ham, bacon, pastrami, corned beef, etc. Though it has been suggested that the reason for using nitrite-containing curing salt is to prevent botulism, a 2018 study by the British Meat Producers Association determined that legally permitted levels of nitrite have no effect on the growth of the Clostridium botulinum bacteria that causes botulism, in line with the UK's Advisory Committee on the Microbiological Safety of Food opinion that nitrites are not required to prevent C. botulinum growth and extend shelf life..

<span class="mw-page-title-main">Dinitrogen trioxide</span> Chemical compound

Dinitrogen trioxide is the inorganic compound with the formula N2O3. It is a nitrogen oxide. It forms upon mixing equal parts of nitric oxide and nitrogen dioxide and cooling the mixture below −21 °C (−6 °F):

<span class="mw-page-title-main">Nitrolic acid</span>

Nitrolic acids are organic compounds with the functional group RC(NO2)=NOH. They are prepared by the reaction of nitroalkanes with base and nitrite sources:

<span class="mw-page-title-main">Transition metal nitrite complex</span> Chemical complexes containing one or more –NO₂ ligands

In organometallic chemistry, transition metal complexes of nitrite describes families of coordination complexes containing one or more nitrite ligands. Although the synthetic derivatives are only of scholarly interest, metal-nitrite complexes occur in several enzymes that participate in the nitrogen cycle.

<span class="mw-page-title-main">Nitrosyl perchlorate</span> Chemical compound

Nitrosyl perchlorate is the inorganic compound with the formula NO(ClO4). A hygroscopic white solid, it is the salt of the nitrosonium cation with the perchlorate anion. It is an oxidant and strong electrophile, but has fallen out of use with the availability of the closely related salt nitrosonium tetrafluoroborate NO(BF4).

References

  1. 1 2 3 Laue W, Thiemann M, Scheibler E, Wiegand KW (2006). "Nitrates and Nitrites". Ullmann's Encyclopedia of Industrial Chemistry . Weinheim: Wiley-VCH. doi:10.1002/14356007.a17_265. ISBN   978-3527306732.
  2. 1 2 3 4 Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. pp. 461–464. ISBN   978-0-08-037941-8.
  3. IUPAC SC-Database Archived 19 June 2017 at the Wayback Machine A comprehensive database of published data on equilibrium constants of metal complexes and ligands
  4. Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 431. ISBN   978-0-08-037941-8.
  5. Ivanov, V. M. (1 October 2004). "The 125th Anniversary of the Griess Reagent". Journal of Analytical Chemistry. 59 (10): 1002–1005. doi:10.1023/B:JANC.0000043920.77446.d7. ISSN   1608-3199. S2CID   98768756.
  6. Sparacino-Watkins, Courtney; Stolz, John F.; Basu, Partha (16 December 2013). "Nitrate and periplasmic nitrate reductases". Chem. Soc. Rev. 43 (2): 676–706. doi:10.1039/c3cs60249d. ISSN   1460-4744. PMC   4080430 . PMID   24141308.
  7. Simon, Jörg; Klotz, Martin G. (2013). "Diversity and evolution of bioenergetic systems involved in microbial nitrogen compound transformations". Biochimica et Biophysica Acta (BBA) - Bioenergetics. 1827 (2): 114–135. doi: 10.1016/j.bbabio.2012.07.005 . PMID   22842521.
  8. 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". Applied Microbiology. 25 (3): 357–62. doi:10.1128/AEM.25.3.357-362.1973. PMC   380811 . PMID   4572891.
  9. 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". Asian-Australasian Journal of Animal Sciences. 31 (8): 1073–1077. doi:10.5713/ajas.17.0675. ISSN   1011-2367. PMC   6043430 . PMID   29531192.
  10. 1 2 3 4 Wilson, Bee (1 March 2018). "Yes, bacon really is killing us". The Guardian. London. ISSN   0261-3077. Archived 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.
  11. Doward, Jamie (23 March 2019). "Revealed: no need to add cancer-risk nitrites to ham". The Observer. London. Archived 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.
  12. De Vries, John (1997). Food Safety and Toxicity. CRC Press. p. 70. ISBN   978-0-8493-9488-1.
  13. sodium nitrite and nitrate facts Accessed 12 Dec 2014
  14. Doyle, Michael P.; Sperber, William H. (23 September 2009). Compendium of the Microbiological Spoilage of Foods and Beverages. Springer. p. 78. ISBN   9781441908261.
  15. 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". Proceedings of the National Academy of Sciences. 111 (22): 8167–72. Bibcode:2014PNAS..111.8167C. doi: 10.1073/pnas.1402965111 . PMC   4050620 . PMID   24843165.
  16. "Is celery juice a viable alternative to nitrites in cured meats?". Office for Science and Society. Retrieved 14 September 2022.
  17. Bagheri, H.; Hajian, A.; Rezaei, M.; Shirzadmehr, A. (2017). "Composite of Cu metal nanoparticles—multiwall carbon nanotubes—reduced graphene oxide as a novel and high performance platform of the electrochemical sensor for simultaneous determination of nitrite and nitrate". Journal of Hazardous Materials. 324 (Pt B): 762–772. doi:10.1016/j.jhazmat.2016.11.055. PMID   27894754.
  18. Binkerd, E. F.; Kolari, O. E. (1 January 1975). "The history and use of nitrate and nitrite in the curing of meat". Food and Cosmetics Toxicology. 13 (6): 655–661. doi:10.1016/0015-6264(75)90157-1. ISSN   0015-6264. PMID   1107192.
  19. Coudray, Guillaume (2017). Cochonneries: Comment la charcuterie est devenue un poison (in French). Paris: La Découverte. pp. 40–70. ISBN   978-2-7071-9358-2.
  20. Lauer, Klaus (1 January 1991). "The history of nitrite in human nutrition: A contribution from German cookery books". Journal of Clinical Epidemiology. 44 (3): 261–264. doi:10.1016/0895-4356(91)90037-A. ISSN   0895-4356. PMID   1999685.
  21. "Guillaume Coudray on the Nitro Meat Cancer Connection". Corporate Crime Reporter. 14 April 2021. Retrieved 13 October 2024.
  22. Meillier, Andrew; Heller, Cara (2015). "Acute Cyanide Poisoning: Hydroxocobalamin and Sodium Thiosulfate Treatments with Two Outcomes following One Exposure Event". Case Reports in Medicine. 2015: 217951. doi: 10.1155/2015/217951 . ISSN   1687-9627. PMC   4620268 . PMID   26543483.
  23. Bebarta, Vikhyat S.; Brittain, Matthew; Chan, Adriano; Garrett, Norma; Yoon, David; Burney, Tanya; Mukai, David; Babin, Michael; Pilz, Renate B.; Mahon, Sari B.; Brenner, Matthew (June 2017). "Sodium Nitrite and Sodium Thiosulfate Are Effective Against Acute Cyanide Poisoning when Administered by Intramuscular Injection". Annals of Emergency Medicine. 69 (6): 718–725.e4. doi:10.1016/j.annemergmed.2016.09.034. ISSN   0196-0644. PMC   5446299 . PMID   28041825.
  24. Victor Meyer (1872). "Ueber die Nitroverbindungen der Fettreihe". Justus Liebig's Annalen der Chemie . 171 (1): 1–56. doi:10.1002/jlac.18741710102.; Victor Meyer, J. Locher (1876). "Ueber die Pseudonitrole, die Isomeren der Nitrolsäuren". Justus Liebig's Annalen der Chemie . 180 (1–2): 133–55. doi:10.1002/jlac.18761800113.; V. Meyer and Stüber (1872). "Vorläufige Mittheilung". Chemische Berichte . 5: 203–05. doi:10.1002/cber.18720050165.; Victor Meyer, O. Stüber (1872). "Ueber die Nitroverbindungen der Fettreihe". Chemische Berichte . 5: 399–406. doi:10.1002/cber.187200501121. S2CID   95188274.; Victor Meyer, A. Rilliet (1872). "Ueber die Nitroverbindungen der Fettreiche. Dritte Mittheilung". Chemische Berichte . 5 (2): 1029–34. doi:10.1002/cber.187200502133.; Victor Meyer, C. Chojnacki (1872). "Ueber die Nitroverbindungen der Fettreihe. Vierte Mittheilung". Chemische Berichte . 5 (2): 1034–38. doi:10.1002/cber.187200502134.
  25. Robert B. Reynolds, Homer Adkins (1929). "The Relationship of the Constitution of Certain Alky Halides to the Formation of Nitroparaffins and Alkyl Nitrites". Journal of the American Chemical Society . 51 (1): 279–87. doi:10.1021/ja01376a037.
  26. Bouvard V, Loomis D, Guyton KZ, Grosse Y, El Ghissassi F, Benbrahim-Tallaa L, et al. (December 2015). "Carcinogenicity of consumption of red and processed meat" . The Lancet Oncology. 16 (16): 1599–1600. doi:10.1016/S1470-2045(15)00444-1. PMID   26514947 . Retrieved 13 October 2024.
  27. Grosse Y, Baan R, Straif K, Secretan B, El Ghissassi F, Cogliano V (August 2006). "Carcinogenicity of nitrate, nitrite, and cyanobacterial peptide toxins" . The Lancet Oncology. 7 (8): 628–629. doi:10.1016/S1470-2045(06)70789-6. PMID   16900606 . Retrieved 13 October 2024.