Nitrosamine

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Nitrosamines are chemical compounds of the chemical structure R₁N(-R₂)-N=O, some of which are carcinogenic.

Contents 1 Usages 2 Occurrences 2.1 Food 2.2 Consumer products 3 Cancer 4 Examples of nitrosamines 5 See also 6 References 7 External links

[edit] Usages

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• Most Rubber products
• Pesticides
• Certain cosmetics

[edit] Occurrences

[edit] Food

Nitrosamines are produced from nitrites and secondary amines, which often occur in the form of proteins. Their formation can occur only under certain conditions, including strongly acidic conditions such as that of the human stomach. High temperatures, as in frying, can also enhance the formation of nitrosamines. These cooking styles may be responsible for thousands of cases of colon cancer per year across the world. The presence of nitrosamines may be identified by the Liebermann's reaction. ^[1]

Under acidic conditions the nitrite forms nitrous acid (HNO₂), which is protonated and splits into the nitrosonium cation N≡O⁺ and water: H₂NO₂⁺ = H₂O + NO⁺. The nitrosonium cation then reacts with an amine to produce nitrosamine.^{[citation needed]}

Nitrosamines are found in many foodstuffs, especially beer, fish, and fish byproducts, and also in meat and cheese products preserved with nitrite pickling salt. The U.S. government established limits on the amount of nitrites used in meat products in order to decrease cancer risk in the population. There are also rules about adding ascorbic acid or related compounds to meat, because they inhibit nitrosamine formation.^{[citation needed]}

[edit] Consumer products

Nitrosamines can be found in tobacco smoke and latex products. A test of party balloons and condoms indicated that many of them release small amounts of nitrosamines.^[1] However, nitrosamines from condoms are not expected to be of toxicological significance.^[2]

[edit] Cancer

Nitrosamines can cause cancers in a wide variety of animal species, a feature that suggests that they may also be carcinogenic in humans. Epidemiological data supports a positive association between nitrite and nitrosamine intake and gastric cancer, between meat and processed meat intake and gastric cancer and oesophageal cancer, but the studies are inconclusive.^[3]

[edit] Examples of nitrosamines

Substance Name	CAS #	Synonyms	Molecular Formula	Physical Appearance	Found in	Sources	Carcinogenicity Category
N-Nitrosonornicotine		NNN	C9H11N3O		Tobacco smoke
4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone		NNK; 4'-(nitrosomethylamino)-1-(3-pyridyl)-1-butanone	C10H13N3O2		Tobacco smoke	[4]
4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanol	76014-81-8	NNAL			Tobacco smoke
N-Nitrosoanabasine	37620-20-5	NAB			Tobacco smoke		IARC-3
N-Nitrosoanatabine	71267-22-6						IARC-3
4-(Methylnitrosoamino)-4-(3-pyridyl)-1-butanol		Iso-NNAL			Tobacco smoke
4-(N-Methylnitrosamino)-4-(3-pyridyl)butyric acid		Iso-NNAC			Tobacco smoke
N-Nitrosodiethylamine	55-18-5	diethylnitrosamide, diethylnitrosamine, N,N-diethylnitrosamine, N-ethyl-N-nitrosoethanamine, diethylnitrosamine, DANA, DENA, DEN, NDEA	C4H10N2O	yellow liquid		[5] [6] [7]	EPA-B2; IARC-2A
N-Nitrosodimethylamine	62-75-9	Dimethylnitrosamine, N,N-Dimethylnitrosamine, NDMA	C2H6N2O				EPA-B2; IARC-2A; OSHA Carcinogen; TLV-A3
2-Nitro-p-phenylenediamine	5307-14-2						IARC-3
N-Nitrosodi-n-butylamide	924-16-3	DBN					EPA-B2; IARC-2B
N-Nitrosodiethanolamine	1116-54-7	NDELA					EPA-B2; IARC-2B
N-Nitrosodiphenylamine	86-30-6						IARC-3
p-Nitrosodiphenylamine	156-10-5						IARC-3
N-Nitrosodi-n-propylamine	621-64-7	NDPA					EPA-B2, IARC-2B
N-Nitrosoethylphenylamine	612-64-6
N-Nitrosomethylphenylamine	614-00-6
2-Nitrodiphenylamine	119-75-5	NDPA, 2-NDPA, 2NO2DPA, Sudan Yellow 1339, C.I. 10335, CI 10335, phenyl 2-nitrophenylamine, 2-nitro-N-phenylaniline,N-phenyl-o-nitroaniline	C12H10N2O2	red crystalline solid	stabilizer of synthetic rubber

[edit] See also

• Nitroamine (without the 's'), compounds of the formula R₂N-NO₂.
• Nitroso, compounds of the formula R-NO

[edit] References

[edit] External links