Metanil Yellow

Metanil Yellow
Names
	IUPAC name Sodium 3-[(4-anilinophenyl)diazenyl]benzenesulfonate
	Other names Acid Yellow 36; Acid Metanil Yellow; Monoazo
Identifiers
CAS Number	587-98-4;
3D model (JSmol)	Interactive image;
ChEBI	CHEBI:87235;
ChemSpider	23621349;
ECHA InfoCard	100.008.736
EC Number	209-608-2;
PubChem CID	3935589;
UNII	7SPF5O5BW8;
CompTox Dashboard (EPA)	DTXSID5041722 ;
	InChI InChI=1S/C18H14N3O3S.Na/c22-25(23,24)18-8-4-7-17(13-18)21-20-16-11-9-15(10-12-16)19-14-5-2-1-3-6-14;/h1-13,19H,(H,22,23,24);/q;+1/p-1 Key: NYGZLYXAPMMJTE-UHFFFAOYSA-M;
	SMILES C1=CC=C(C=C1)NC2=CC=C(C=C2)N=NC3=CC(=CC=C3)S(=O)(=O)[O-].[Na+];
Properties
Chemical formula	C18H15N3NaO3S
Molar mass	376.39 g·mol−1
Melting point	> 250 °C
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Metanil Yellow (Acid Yellow 36) is a dye of the azo class. In analytical chemistry, it is used as a pH indicator and it has a color change from red to yellow between pH 1.2 and 3.2.

Although illegal for food use, Metanil Yellow has been used as an adulterant in turmeric- and pigeon pea-based food products, particularly in India.

Animal studies have suggested that Metanil Yellow is neurotoxic and hepatotoxic.

References

1 2 R. W. Sabnis (2007). Handbook of Acid-Base Indicators. Boca Raton: CRC Press. p. 219. ISBN 978-0-8493-8219-2.
↑ Dhakal, S; Chao, K; Schmidt, W; Qin, J; Kim, M; Chan, D (2016). "Evaluation of Turmeric Powder Adulterated with Metanil Yellow Using FT-Raman and FT-IR Spectroscopy". Foods. 5 (2): 36. doi:10.3390/foods5020036. PMC 5302347. PMID 28231130.
1 2 Nagaraja, T. N; Desiraju, T (1993). "Effects of chronic consumption of metanil yellow by developing and adult rats on brain regional levels of noradrenaline, dopamine and serotonin, on acetylcholine esterase activity and on operant conditioning". Food and Chemical Toxicology. 31 (1): 41–4. doi:10.1016/0278-6915(93)90177-z. PMID 8095244.
↑ Nath, P. P., Sarkar, K., Tarafder, P., Mondal, M., Das, K. and Paul, G (2015). "Practice of using metanil yellow as food colour to process food in unorganized sector of West Bengal" (PDF). International Food Research Journal. 22 (4): 1424–1428.{{cite journal}}: CS1 maint: multiple names: authors list (link)
↑ "Common food adulterants in India", India Today, New Delhi, October 19, 2018
↑ Saxena, B; Sharma, S (2015). "Food Color Induced Hepatotoxicity in Swiss Albino Rats, Rattus norvegicus". Toxicology International. 22 (1): 152–157. doi:10.4103/0971-6580.172286 (inactive 1 July 2025). PMC 4721164. PMID 26862277.{{cite journal}}: CS1 maint: DOI inactive as of July 2025 (link)

[sabnis-1] 1 2 R. W. Sabnis (2007). Handbook of Acid-Base Indicators. Boca Raton: CRC Press. p. 219. ISBN 978-0-8493-8219-2.

[2] Dhakal, S; Chao, K; Schmidt, W; Qin, J; Kim, M; Chan, D (2016). "Evaluation of Turmeric Powder Adulterated with Metanil Yellow Using FT-Raman and FT-IR Spectroscopy". Foods. 5 (2): 36. doi:10.3390/foods5020036. PMC 5302347. PMID 28231130.

[Nagaraja-3] 1 2 Nagaraja, T. N; Desiraju, T (1993). "Effects of chronic consumption of metanil yellow by developing and adult rats on brain regional levels of noradrenaline, dopamine and serotonin, on acetylcholine esterase activity and on operant conditioning". Food and Chemical Toxicology. 31 (1): 41–4. doi:10.1016/0278-6915(93)90177-z. PMID 8095244.

[4] Nath, P. P., Sarkar, K., Tarafder, P., Mondal, M., Das, K. and Paul, G (2015). "Practice of using metanil yellow as food colour to process food in unorganized sector of West Bengal" (PDF). International Food Research Journal. 22 (4): 1424–1428.{{cite journal}}: CS1 maint: multiple names: authors list (link)

[5] "Common food adulterants in India", India Today, New Delhi, October 19, 2018

[6] Saxena, B; Sharma, S (2015). "Food Color Induced Hepatotoxicity in Swiss Albino Rats, Rattus norvegicus". Toxicology International. 22 (1): 152–157. doi:10.4103/0971-6580.172286 (inactive 1 July 2025). PMC 4721164. PMID 26862277.{{cite journal}}: CS1 maint: DOI inactive as of July 2025 (link)