Methylparaben (methyl paraben) one of the

parabens Parabens are organic compounds that are commonly used as preservatives in Cosmetics, cosmetic and pharmaceutical products. They are esters of parahydroxybenzoic acid (also known as 4-hydroxybenzoic acid). Chemistry Structure and structure Pa ...

, is a preservative with the chemical formula . It is the

methyl In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula (whereas normal methane has the formula ). In formulas, the group is often abbreviated as ...

ester In chemistry, an ester is a compound derived from an acid (either organic or inorganic) in which the hydrogen atom (H) of at least one acidic hydroxyl group () of that acid is replaced by an organyl group (R). These compounds contain a distin ...

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.

Natural occurrences

Methylparaben serves as a

pheromone A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavio ...

for a variety of insects and is a component of

queen mandibular pheromone Queen mandibular pheromone, or QMP, is a honey bee pheromone produced by the queen and fed to her attendants who share it with the rest of the colony to give the colony the sense of belonging to the queen. Newly emerged queens produce very little Q ...

. It is a pheromone in wolves produced during

estrus The estrous cycle (, originally ) is a set of recurring physiological changes induced by reproductive hormones in females of mammalian subclass Theria. Estrous cycles start after sexual maturity in females and are interrupted by anestrous phas ...

associated with the behavior of alpha male wolves preventing other males from mounting females in heat.

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 E numbers, short for Europe numbers, are codes for substances used as food additives, including those found naturally in many foods, such as vitamin C, for use within the European Union (EU) and European Free Trade Association (EFTA). Commonly ...

E218. Methylparaben is commonly used as a

fungicide Fungicides are pesticides used to kill parasitic fungi or their spores. Fungi can cause serious damage in agriculture, resulting in losses of yield and quality. Fungicides are used both in agriculture and to fight fungal infections in animals, ...

in ''

Drosophila ''Drosophila'' (), from Ancient Greek δρόσος (''drósos''), meaning "dew", and φίλος (''phílos''), meaning "loving", is a genus of fly, belonging to the family Drosophilidae, whose members are often called "small fruit flies" or p ...

'' food media at 0.1%. To ''Drosophila'', methylparaben is

toxic Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a subst ...

at higher concentrations, has an

estrogen Estrogen (also spelled oestrogen in British English; see spelling differences) is a category of sex hormone responsible for the development and regulation of the female reproductive system and secondary sex characteristics. There are three ...

ic effect (mimicking estrogen in rats and having anti-

androgenic An androgen (from Greek ''andr-'', the stem of the word meaning ) is any natural or synthetic steroid hormone that regulates the development and maintenance of male characteristics in vertebrates by binding to androgen receptors. This includes ...

activity), and slows the growth rate in the larval and pupal stages at 0.2%.

Safety

Methylparaben is practically non-toxic by both oral and

parenteral In pharmacology and toxicology, a route of administration is the way by which a drug, fluid, poison, or other substance is taken into the body. Routes of administration are generally classified by the location at which the substance is applied. ...

administration in animals. In a population with normal skin, methylparaben is practically non-irritating and non-sensitizing; however, allergic reactions to ingested parabens have been reported. 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. Some controversy exists about whether methylparaben or propylparabens are harmful at concentrations typically used in body care or cosmetics. Methylparaben and

propylparaben Propylparaben (also spelled propyl paraben) is the ''n''-propyl ester of ''p''-hydroxybenzoic acid. It occurs as a natural substance found in many plants and some insects. Additionally, it can be manufactured synthetically for use in cosmetics, ...

are considered

generally recognized as safe Generally recognized as safe (GRAS) is a United States Food and Drug Administration (FDA) designation that a chemical or substance added to food is considered safe by experts under the conditions of its intended use. An ingredient with a GRAS d ...

(GRAS) by the

USFDA The United States Food and Drug Administration (FDA or US FDA) is a federal agency of the Department of Health and Human Services. The FDA is responsible for protecting and promoting public health through the control and supervision of food ...

for food and cosmetic antibacterial preservation. Methylparaben is readily metabolized by common soil bacteria, making it completely biodegradable. Methylparaben is readily absorbed from the gastrointestinal tract or through the skin. It is

hydrolyzed Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolysi ...

to ''p''-hydroxybenzoic acid and rapidly excreted in urine without accumulating in the body. Methylparaben applied on the skin may react with

UVB Ultraviolet radiation, also known as simply UV, is electromagnetic radiation of wavelengths of 10–400 nanometers, shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight and constitutes about 10% of the ...

, leading to increased skin aging and DNA damage.

References

External links

Methylparaben
at Hazardous Substances Data Bank
Methylparaben
at Household Products Database * European Commission Scientific Committee on Consumer Products Extended Opinion on the Safety Evaluation of Parabens (2005

{{Phenolic acid Methyl esters Parabens E-number additives Semiochemicals Insect pheromones ja:メチルパラベン