Butylparaben
Encyclopedia
Butylparaben, or butyl paraben, is a member of the paraben family, which has the formula C4H9(C6H4(OH)COO). It is used as an antimicrobial
preservative in cosmetics such as eye shadow, foundation, sunscreen, facial moisturizer and skin anti-aging treatment. It is also used in medication suspensions, and as a flavoring additive in food. Butylparaben and the paraben family have come to public attention recently, due to a study reporting low concentrations of parabens in breast tumors, around tissue. However, parabens have not been proven to cause breast cancer. Estimates by the U.S. Food and Drug Administration
and the Center for Food Safety and Applied Nutrition
have found that the average person is exposed to about 37 ng of butylparaben per day.
to its corresponding carboxylic acid
in basic solutions. The antimicrobial
activity of parabens
increases with increasing alkyl chain length (methylparaben
<ethylparaben
butylparaben
antimicrobial
activity is retained across the pH
range of 4 to 8. Antimicrobial activity is usually enhanced by combining butylparaben with other biocides such as formaldehyde
releasers, Isothiazolinones, or Phenoxyethanol
. It has been shown that butylparaben has the ability to cross body barriers, and enter the body through the lungs, GI tract, and skin
epithelium.
and the World Health Organization
. Butylparaben can also be found in the sewage coming from bathroom pipes where people wash off makeup, and other skin care products. A study in 2001 found that concentrations of parabens in Danish sewage facilities could be up to 100 to 1000 times below the acute or chronic effect concentrations of butylparaben. An accurate risk assessment could not be made, however, based on the limited data available on the acute and chronic concentration levels of parabens.
with 1-butanol in the presence of an acid catalyst, such as sulfuric acid
. It is available for commercial purchase from a number of different distributors, including Ashland Inc., J.T. Baker, and Penta Manufacturing Co.
. In the paraben family, butylparaben appears to be the best antifungal agent. It is particularly active against molds and yeasts, and less active against bacteria.
(SCCP) of the European Union
published that there is not enough data to perform risk assessments for butylparaben in humans. Despite this publishing, Denmark banned butylparaben in products for use by children younger than tthe age of three, in March of 2011. Butylparaben is presently regulated by the U.S. Food and Drug Administration
as a synthetic flavoring and adjuvant. It is recommended that it be used in the minimum amount necessary to achieve its intended effect. Butylparaben is also regulated by the United States Environmental Protection Agency
under the Toxic Substances Control Act of 1976
and the Federal Insecticide, Fungicide, and Rodenticide Act
. Its pesticide registration was canceled in 1998.
(CIR), an industry sponsored organization under the U.S. Food and Drug Administration
that encourages researchers to submit their work, has reopened their safety assessment for parabens. The organization reviews and publishes credible research, and looks to answer the following questions: Is there a causal link between breast cancer and parabens? What are the concentrations of paraben that cause acute and chronic harm? Are there reproductive malformations caused by paraben exposure? These questions and more are looking to be answered with the implementation of new research techniques and resources.
Antimicrobial
An anti-microbial is a substance that kills or inhibits the growth of microorganisms such as bacteria, fungi, or protozoans. Antimicrobial drugs either kill microbes or prevent the growth of microbes...
preservative in cosmetics such as eye shadow, foundation, sunscreen, facial moisturizer and skin anti-aging treatment. It is also used in medication suspensions, and as a flavoring additive in food. Butylparaben and the paraben family have come to public attention recently, due to a study reporting low concentrations of parabens in breast tumors, around tissue. However, parabens have not been proven to cause breast cancer. Estimates by the U.S. Food and Drug Administration
Food and Drug Administration
The Food and Drug Administration is an agency of the United States Department of Health and Human Services, one of the United States federal executive departments...
and the Center for Food Safety and Applied Nutrition
Center for Food Safety and Applied Nutrition
The Center for Food Safety and Applied Nutrition is the branch of the United States Food and Drug Administration that regulates food, dietary supplements, and cosmetics .-Area of regulation:...
have found that the average person is exposed to about 37 ng of butylparaben per day.
Properties
Butylparaben is a fine, colorless, odorless, crystalline solid at room temperature. The molecular formula of butylparaben is C11H14O3; its molecular weight is . Butylparaben is soluble in acetone, ethanol, and chloroform, and slightly soluble in H2O. It has a melting point of 68- and undergoes hydrolysisHydrolysis
Hydrolysis is a chemical reaction during which molecules of water are split into hydrogen cations and hydroxide anions in the process of a chemical mechanism. It is the type of reaction that is used to break down certain polymers, especially those made by condensation polymerization...
to its corresponding carboxylic acid
Carboxylic acid
Carboxylic acids are organic acids characterized by the presence of at least one carboxyl group. The general formula of a carboxylic acid is R-COOH, where R is some monovalent functional group...
in basic solutions. The antimicrobial
Antimicrobial
An anti-microbial is a substance that kills or inhibits the growth of microorganisms such as bacteria, fungi, or protozoans. Antimicrobial drugs either kill microbes or prevent the growth of microbes...
activity of parabens
Parabens
Parabens are a class of chemicals widely used as preservatives in the cosmetic and pharmaceutical industries. Parabens are effective preservatives in many types of formulas. These compounds, and their salts, are used primarily for their bactericidal and fungicidal properties...
increases with increasing alkyl chain length (methylparaben
Methylparaben
Methylparaben, also methyl paraben, one of the parabens, is a preservative with the chemical formula CH3. It is the methyl ester of p-hydroxybenzoic acid.-Occurrence:...
<ethylparaben
Ethylparaben
Ethylparaben is the ethyl ester of p-hydroxybenzoic acid. Its formula is HO-C6H4-CO-O-CH2CH3. It is a member of the class of compounds known as parabens.It is used as an antifungal preservative...
Butylparaben
Butylparaben, or butyl paraben, is a member of the paraben family, which has the formula C4H9. It is used as an antimicrobial preservative in cosmetics such as eye shadow, foundation, sunscreen, facial moisturizer and skin anti-aging treatment. It is also used in medication suspensions, and as a...
Antimicrobial
An anti-microbial is a substance that kills or inhibits the growth of microorganisms such as bacteria, fungi, or protozoans. Antimicrobial drugs either kill microbes or prevent the growth of microbes...
activity is retained across the pH
PH
In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...
range of 4 to 8. Antimicrobial activity is usually enhanced by combining butylparaben with other biocides such as formaldehyde
Formaldehyde
Formaldehyde is an organic compound with the formula CH2O. It is the simplest aldehyde, hence its systematic name methanal.Formaldehyde is a colorless gas with a characteristic pungent odor. It is an important precursor to many other chemical compounds, especially for polymers...
releasers, Isothiazolinones, or Phenoxyethanol
Phenoxyethanol
Phenoxyethanol is an organic chemical compound, a glycol ether often used in dermatological products such as skin creams and sunscreen. It is a colorless oily liquid. It is a bactericide , often used in place of sodium azide in biological buffers as 2-phenoxyethanol is less toxic and non-reactive...
. It has been shown that butylparaben has the ability to cross body barriers, and enter the body through the lungs, GI tract, and skin
Skin
-Dermis:The dermis is the layer of skin beneath the epidermis that consists of connective tissue and cushions the body from stress and strain. The dermis is tightly connected to the epidermis by a basement membrane. It also harbors many Mechanoreceptors that provide the sense of touch and heat...
epithelium.
Occurrence
Butylparaben is used as a preservative in some foods, cosmetics and drugs to prevent decomposition. It is added to low-ionic strength solutions to retard microbial growth. In 2003, butylparaben was cleared to be used as a flavor additive in food by the Food and Agriculture OrganizationFood and Agriculture Organization
The Food and Agriculture Organization of the United Nations is a specialised agency of the United Nations that leads international efforts to defeat hunger. Serving both developed and developing countries, FAO acts as a neutral forum where all nations meet as equals to negotiate agreements and...
and the World Health Organization
World Health Organization
The World Health Organization is a specialized agency of the United Nations that acts as a coordinating authority on international public health. Established on 7 April 1948, with headquarters in Geneva, Switzerland, the agency inherited the mandate and resources of its predecessor, the Health...
. Butylparaben can also be found in the sewage coming from bathroom pipes where people wash off makeup, and other skin care products. A study in 2001 found that concentrations of parabens in Danish sewage facilities could be up to 100 to 1000 times below the acute or chronic effect concentrations of butylparaben. An accurate risk assessment could not be made, however, based on the limited data available on the acute and chronic concentration levels of parabens.
Preparation
Butylparaben is prepared by the esterification of 4-Hydroxybenzoic acid4-Hydroxybenzoic acid
4-Hydroxybenzoic acid is a monohydroxybenzoic acid, a phenolic derivative of benzoic acid. It is a white crystalline solid that is slightly soluble in water and chloroform but more soluble in polar organic solvents such as alcohols and acetone...
with 1-butanol in the presence of an acid catalyst, such as sulfuric acid
Sulfuric acid
Sulfuric acid is a strong mineral acid with the molecular formula . Its historical name is oil of vitriol. Pure sulfuric acid is a highly corrosive, colorless, viscous liquid. The salts of sulfuric acid are called sulfates...
. It is available for commercial purchase from a number of different distributors, including Ashland Inc., J.T. Baker, and Penta Manufacturing Co.
Uses and reactions
Butylparaben is one of the most commonplace bactericidal/fungicidal additives to cosmetics, probably due to its low cost, and efficiency as a microbial agent. It is reported by the EWG to be found in almost 3000 cosmetic products including eye shadow, facial moisturizer/treatment, anti-aging cream, foundation, and sunscreen. In most cosmetics paraben is used at low levels, ranging from 0.01 to 0.3%. Numerous members of the paraben family are found in fruit and vegetable products, such as barley, flax seed, and grapes. Butylparaben can also be found in low concentrations in liquid and solid medication suspensions, such as tylenol (acetaminophen) and ibuprofenIbuprofen
Ibuprofen is a nonsteroidal anti-inflammatory drug used for relief of symptoms of arthritis, fever, as an analgesic , especially where there is an inflammatory component, and dysmenorrhea....
. In the paraben family, butylparaben appears to be the best antifungal agent. It is particularly active against molds and yeasts, and less active against bacteria.
History
Butylparaben has been used in cosmetic products for over 80 years. Its use in pharmaceutical products has occurred since 1924. In December 2010 the Scientific Committee on Consumer ProductsScientific Committee on Consumer Products
The Scientific Committee on Consumer Products is one of the independent scientific committees managed by the Directorate-General for Health and Consumer Protection of the European Commission, which provide scientific advice to the Commission on issues related to non-food issues.- Activities :The...
(SCCP) of the European Union
European Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...
published that there is not enough data to perform risk assessments for butylparaben in humans. Despite this publishing, Denmark banned butylparaben in products for use by children younger than tthe age of three, in March of 2011. Butylparaben is presently regulated by the U.S. Food and Drug Administration
Food and Drug Administration
The Food and Drug Administration is an agency of the United States Department of Health and Human Services, one of the United States federal executive departments...
as a synthetic flavoring and adjuvant. It is recommended that it be used in the minimum amount necessary to achieve its intended effect. Butylparaben is also regulated by the United States Environmental Protection Agency
United States Environmental Protection Agency
The U.S. Environmental Protection Agency is an agency of the federal government of the United States charged with protecting human health and the environment, by writing and enforcing regulations based on laws passed by Congress...
under the Toxic Substances Control Act of 1976
Toxic Substances Control Act of 1976
The Toxic Substances Control Act is a United States law, passed by the United States Congress in 1976, that regulates the introduction of new or already existing chemicals. It grandfathered most existing chemicals, in contrast to the Registration, Evaluation and Authorization of Chemicals ...
and the Federal Insecticide, Fungicide, and Rodenticide Act
Federal Insecticide, Fungicide, and Rodenticide Act
The Federal Insecticide, Fungicide, and Rodenticide Act , et seq. is a United States federal law that set up the basic U.S. system of pesticide regulation to protect applicators, consumers, and the environment. It is administered by the Environmental Protection Agency and the appropriate...
. Its pesticide registration was canceled in 1998.
Safety and toxicology
Exposure to butylparaben can occur via inhalation, ingestion and eye or skin contact. Ingestion is not considered a safety concern because butylparaben is quickly absorbed, metabolized and excreted. Evidence of the absorbance of butylparaben through the skin, however, has shown that it can last much longer, and accumulate in epithelial tissue. In mice, the Median lethal dose (LD50) is about 5000 mg/kg body weight.Endocrine disruption
Butylparaben is estrogenic, meaning it mimics natural estrogen in the body. For example, parabens can bind to estrogen receptors and regulate estrogen responsive gene products in experimental cell systems. Long-chained parabens, like butylparaben, are more estrogenic than short-chained parabens, like methyl- or ethylparaben. This is likely because long-chained parabens are more lipophilic/hydrophobic, and have a higher affinity for estrogen receptors.Antiandrogenic
Butylparaben can decrease sperm function and alter metabolic hormones. Rats exposed to a high concentration of butylparaben during pregnancy gave birth to fewer pups, and pups with malformed reproductive organs. A study on humans has found that reduced sperm counts and functional abnormalities in sperm are associated with elevated levels of butylparaben.Carcinogenicity
Butylparaben has been found in small concentrations in human breast fat and breast tumors. A study by Darbre et al. (2004) has suggested that the underarm application of paraben-containing deodorants may attribute to breast cancer. Oral administration of butylparaben to eight-week-old rats has caused tumors such as thymic lymphoma, non-thymic lyphoid leukemia, and myeloid leukemia. Similar studies, however, have found no significant increase in tumors upon butylparaben administration. The carcinogenicity of butylparaben is currently listed as "possible" on the EWG website.Ongoing/future research
Butylparaben is not considered to be a safety risk at this time for many governmental agencies around the world, but it is under close scrutiny, and the subject of ongoing research. The Cosmetic Ingredient ReviewCosmetic Ingredient Review
The Cosmetic Ingredient Review , based in Washington, D.C., assesses and reviews the safety of ingredients in cosmetics and publishes the results in peer-reviewed scientific literature...
(CIR), an industry sponsored organization under the U.S. Food and Drug Administration
Food and Drug Administration
The Food and Drug Administration is an agency of the United States Department of Health and Human Services, one of the United States federal executive departments...
that encourages researchers to submit their work, has reopened their safety assessment for parabens. The organization reviews and publishes credible research, and looks to answer the following questions: Is there a causal link between breast cancer and parabens? What are the concentrations of paraben that cause acute and chronic harm? Are there reproductive malformations caused by paraben exposure? These questions and more are looking to be answered with the implementation of new research techniques and resources.