Methylparaben

Methylparaben (methyl paraben) one of the parabens, is a preservative with the chemical formula CH₃O₂CC₆H₄OH. It is the methyl ester of p-hydroxybenzoic acid. Several related esters are known (ethyl-, propyl-, butylparaben). Together they are the most common preservatives in cosmetics and foods. Among their advantages, parabens are inexpensive, colorless, stable, odorless, and readily biodegraded.^[2]

Methylparaben

Names
Preferred IUPAC name Methyl 4-hydroxybenzoate
Other names Methyl paraben Methyl p-hydroxybenzoate Methyl parahydroxybenzoate Nipagin M E number E218 Tegosept Mycocten
Identifiers
CAS Number	99-76-3 Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:31835 N
ChEMBL	ChEMBL325372 Y
ChemSpider	7176 Y
ECHA InfoCard	100.002.532
E number	E218 (preservatives)
IUPHAR/BPS	6273
KEGG	D01400 Y
PubChem CID	7456
UNII	A2I8C7HI9T Y
CompTox Dashboard (EPA)	DTXSID4022529
InChI InChI=1S/C8H8O3/c1-11-8(10)6-2-4-7(9)5-3-6/h2-5,9H,1H3 Y Key: LXCFILQKKLGQFO-UHFFFAOYSA-N Y InChI=1/C8H8O3/c1-11-8(10)6-2-4-7(9)5-3-6/h2-5,9H,1H3 Key: LXCFILQKKLGQFO-UHFFFAOYAH
SMILES COC(=O)c1ccc(O)cc1
Properties
Chemical formula	C8H8O3
Molar mass	152.149 g·mol−1
Appearance	Colorless crystals or white crystalline powder[1]
Density	1.383 g/cm3
Melting point	131 °C (268 °F; 404 K)
Boiling point	265 °C (509 °F; 538 K)
UV-vis (λmax)	255 nm (methanol)
Magnetic susceptibility (χ)	−88.7·10−6 cm3/mol
Hazards
NFPA 704 (fire diamond)	1 1 0
Related compounds
Related Parabens	Ethylparaben Propylparaben Butylparaben
Related compounds	Methyl salicylate (ortho isomer)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

UV-visible spectrum of methylparaben

Natural occurrences

Methylparaben serves as a pheromone for a variety of insects^[3] and is a component of queen mandibular pheromone.

It is a pheromone in wolves produced^{[clarification needed]} during estrus associated with the behavior of alpha male wolves preventing other males from mounting females in heat.^[4][5]

Uses

Methylparaben is an anti-fungal agent often used in a variety of cosmetics and personal-care products. It is also used as a food preservative and has the E number E218.

Methylparaben is commonly used as a fungicide in Drosophila food media at 0.1%.^[6] To Drosophila, methylparaben is toxic at higher concentrations, has an estrogenic effect (mimicking estrogen in rats and having anti-androgenic activity), and slows the growth rate in the larval and pupal stages at 0.2%.^[7]

Safety

Methylparaben is practically non-toxic by both oral and parenteral administration in animals.^[8] In a population with normal skin, methylparaben is practically non-irritating and non-sensitizing; however, allergic reactions to ingested parabens have been reported.^[8] A 2008 study found no competitive binding for human estrogen and androgen receptors for methylparaben, but varying levels of competitive binding were seen with butyl- and isobutyl-paraben.^[9]

Some controversy exists about whether methylparaben or propylparabens are harmful at concentrations typically used in body care or cosmetics.^[10] Methylparaben and propylparaben are considered generally recognized as safe (GRAS) by the USFDA for food and cosmetic antibacterial preservation.^[11] Methylparaben is readily metabolized by common soil bacteria, making it completely biodegradable.

Methylparaben is readily absorbed from the gastrointestinal tract or through the skin.^[8] It is hydrolyzed to p-hydroxybenzoic acid and rapidly excreted in urine without accumulating in the body.^[8]

Methylparaben applied on the skin may react with UVB, leading to increased skin aging and DNA damage.^[12][13]