Galaxolide (trade name; also known as Abbalide, Pearlide, Astrolide, Musk 50, Polarlide; chemical name 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8,-hexamethyl-cyclopenta[g]benzopyran or HHCB, hexamethylindanopyran) is a synthetic musk with a clean sweet musky floral woody odor used in fragrances. It is one of the musk components that perfume and cologne manufacturers use to add a musk odor to their products. Galaxolide was first synthesized in 1965, and used in the late 1960s in some fabric softeners and detergents.[1] High concentrations were also incorporated in fine fragrances.
Galaxolide is the trade name from International Flavors & Fragrances Inc. (IFF) for the fragrance material with CAS Registry Number 1222-05-5 and CAS chemical name cyclopenta(g)-2-benzopyran, 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethyl-.
Galaxolide is also known by its IUPAC name 4,6,6,7,8,8-hexamethyl-1,3,4,6,7,8-hexahydro-cyclopenta[g]-isochromene and the more commonly used acronym of the chemical name 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8,-hexamethyl-cyclopenta[g]benzopyran (HHCB). The abbreviation for this chemical name, HHCB, is commonly used for galaxolide in various publications. Galaxolide may also be known as hexamethylindanopyran under the International Nomenclature of Cosmetic Ingredients (INCI).
Physical-chemical properties
Galaxolide is a mixture of isomers. It has chiral centers at carbon atom 4 and 7. The isomers are (4R,7R), (4R,7S), (4S,7S) and (4S, 7R). Galaxolide has a molecular formula of C18H26O and a molecular weight of 258.4 g/mol. At room temperature, it occurs as a highly viscous liquid. Its melting point is -20°C and its boiling point is estimated to be 330°C based on a boiling point of 160°C at 4hPa.[2]
History
Galaxolide was discovered at IFF in the 1960s, by Heering and Beets.[3]
It was first synthesized in 1965 and its discovery was mainly due to the work by Beets on the osmophoric group of the polycyclic musks, where they tried to improve existing synthetic musks by making them more stable and hydrophobic [4]
Odor
Galaxolide has become the key synthetic musk ingredient belonging to the polycyclic musk group as defined by the International Fragrance Association (IFRA). Its odor is described as a “clean”, sweet, floral, woody musk,[5] Research has shown that it is in particular the (4S,7R) and the (4S, 7S) forms of galaxolide that are the most powerful musk notes, with odor thresholds of 1ng/L or less.[6]
Environmental data
Galaxolide has a measured bioconcentration factor (BCF) in fish in a range of 600-1600 and a log octanol-water partition coefficient (Log Kow) of around 5.5 (5.3 – 5.9).[2]
Given its lack of bioaccumulation and toxicity, the EU determined that galaxolide does not meet the criteria for being a substance classified as Persistent, Bioaccumulative and Toxic to the environment (PBT).[7][8] However, the EPA's assessment of galaxolide found it to be moderately persistent and bioaccumulative and highly toxic to aquatic organisms.[9] The EPA's PBT Profiler also finds Galaxolide to exceed the EPA's criteria as a PBT.[10]
Galaxolide degrades in the environment to primary degradants with log Kow <4 and further to more hydrophilic products with Log Kow of <1.[2]
Galaxolide is classified as H410: "Very toxic to aquatic life with long lasting effects" under EU CLP classification rules.[2]
Although there have been reports of galaxolide in environmental compartments,[11][12][13] these studies have been made part of galaxolide's environmental safety reviews by various authorities, who have deemed that there is no need for risk reduction measures.[7][14][15]
Galaxolide contamination has been detected in the Great Lakes. In a study of lake sediment in Lake Erie found galaxolide levels to be doubling every 8–16 years, raising question of its bioaccumulative properties. [16] Galaxolide was detected in 92% of water samples from Lake Michigan.[17]
In 2015 a GreenScreen® for Safer Chemicals assessment of Galaxolide assigned Galaxolide a score of Benchmark 1. Benchmark 1 is assigned to chemicals of highest concern whose use is recommended to be avoided. Specifically, the GreenScreen® assigned the Benchmark 1 score due to Galaxolide's high persistent, bioaccumulative and aquatic toxicity properties. [18]
Galaxolide has been shown to be removed by ozonation in wastewaters treatment plants.[19] Yet, studies show, it is commonly detected in rivers,[20] drinking water,[21] lake sediment[22] and fish tissue.[23]
Human health
Galaxolide is not an irritant, not toxic, not a CMR substance nor a sensitizer.[2] Based on test data, the EU Scientific Committee for Consumer Safety included galaxolide in their proposal for extending the allergen information on cosmetic products as it claims to have seen only up to 100 individual cases worldwide in the last several decades who have reported irritation or allergic reactions to galaxolide through the use of cosmetic products.[24]
Galaxolide has been reported to be found in human biomonitoring studies and its presence in human tissue has been evaluated by several scientific authorities. For example, Galaxolide was detected in 97% of breast milk samples in mothers from Massachusetts in a 2004 study.[25] A 2009 study detected Galaxolide in the blood plasma of 91% of the study participants. [26]
Extensive investigations into the presence of galaxolide in biomonitoring studies,[13][27] have been completed and evaluated by various regulatory authorities. The outcome of all those studies is that galaxolide is safe for use in consumer products.[7][28][29]
Regulatory and safety status
In 2002, The Scientific Committee on Cosmetics and Non-Food Products (SCCNFP), the expert scientific board that advises the European Commission on human health issues, reviewed the human safety of galaxolide, when used in cosmetic products, and issued a final opinion on 17 September 2002.[28] The SCCNFP stated that "...HHCB [galaxolide] can be safely used as a fragrance ingredient in cosmetic products without any restriction for its use."
In March 2003, the European Chemicals Bureau (ECB) concluded that galaxolide is not a persistent, bioaccumulative and toxic substance (PBT) according to the ECB criteria and removed galaxolide from their draft list of PBTs.[8]
Under the EU Existing Substances Directive, galaxolide is listed in the 4th Priority List of Substances for review by the EU. This Priority List was the 4th list compiled by the EU of high volume substances that were to be evaluated by the Member States’ Competent Authorities, as part of the requirements of EU Council regulation 793/93 “On the Evaluation and Control of the risk of existing substances”. The EU published the final report for this study in 2008[7] and concluded that for all human health and environmental endpoints, "There is at present no need for further information and/or testing and no need for risk reduction measures".
Additionally the European Union Scientific Committee for Health and Environmental Risks (SCHER), an advisory body to the European Commission, independently reviewed the environmental, human health, and indirect exposure risk assessment, and agreed with all of the conclusions from the EU experts on the outcome that, "There is at present no need for further information and/or testing and no need for risk reduction measures". The SCHER opinions for galaxolide are available for the environment,[14] for human health[30] and for human health though indirect exposure.[31]
As part of the obligations under the EU's Registration, Evaluation and Authorization of Chemicals (REACH),[32] the producers and importers of galaxolide on the EU market have registered galaxolide in December 2010[2] with the European Chemicals Agency in Helsinki.
In 2010, the state of Oregon added galaxolide to its Priority Persistent Pollutants (P3) list. This is a list of persistent, bioaccumulative toxics that have a documented effect on human health, wildlife and aquatic life.[33]
On June 22, 2016, the Frank R. Lautenberg Chemical Safety for the 21st Century Act (Lautenberg Chemical Safety Act) was signed into law in the United States. The Lautenberg Chemical Safety Act amends the Toxic Substances Control Act of 1976 (TSCA), the nation's primary chemicals management law. On December 20, 2019, EPA finalized the designation of 20 chemical substances as a high-priority for risk evaluation under TSCA, Galaxolide is one of these high-priority chemicals being evaluated for risk. [34]
Related Research Articles
Perfume is a mixture of fragrant essential oils or aroma compounds (fragrances), fixatives and solvents, usually in liquid form, used to give the human body, animals, food, objects, and living-spaces an agreeable scent. Perfumes can be defined as substances that emit and diffuse a pleasant and fragrant odor. They consist of manmade mixtures of aromatic chemicals and essential oils. The 1939 Nobel Laureate for Chemistry, Leopold Ružička stated in 1945 that "right from the earliest days of scientific chemistry up to the present time, perfumes have substantially contributed to the development of organic chemistry as regards methods, systematic classification, and theory."
A biocide is defined in the European legislation as a chemical substance or microorganism intended to destroy, deter, render harmless, or exert a controlling effect on any harmful organism. The US Environmental Protection Agency (EPA) uses a slightly different definition for biocides as "a diverse group of poisonous substances including preservatives, insecticides, disinfectants, and pesticides used for the control of organisms that are harmful to human or animal health or that cause damage to natural or manufactured products". When compared, the two definitions roughly imply the same, although the US EPA definition includes plant protection products and some veterinary medicines.
The Toxic Substances Control Act (TSCA) is a United States law, passed by the 94th United States Congress in 1976 and administered by the United States Environmental Protection Agency (EPA), that regulates chemicals not regulated by other U.S. federal statutes, including chemicals already in commerce and the introduction of new chemicals. When the TSCA was put into place, all existing chemicals were considered to be safe for use and subsequently grandfathered in. Its three main objectives are to assess and regulate new commercial chemicals before they enter the market, to regulate chemicals already existing in 1976 that posed an "unreasonable risk of injury to health or the environment", as for example PCBs, lead, mercury and radon, and to regulate these chemicals' distribution and use.
Persistent organic pollutants (POPs) are organic compounds that are resistant to degradation through chemical, biological, and photolytic processes. They are toxic chemicals that adversely affect human health and the environment around the world. Because they can be transported by wind and water, most POPs generated in one country can and do affect people and wildlife far from where they are used and released.
Brominated flame retardants (BFRs) are organobromine compounds that have an inhibitory effect on combustion chemistry and tend to reduce the flammability of products containing them. The brominated variety of commercialized chemical flame retardants comprise approximately 19.7% of the market. They are effective in plastics and textile applications like electronics, clothes and furniture.
Methoxychlor is a synthetic organochloride insecticide, now obsolete.
Dibutyl phthalate (DBP) is an organic compound which is commonly used as a plasticizer because of its low toxicity and wide liquid range. With the chemical formula C6H4(CO2C4H9)2, it is a colorless oil, although commercial samples are often yellow.
Decabromodiphenyl ether is a brominated flame retardant which belongs to the group of polybrominated diphenyl ethers (PBDEs). It was commercialised in the 1970s and was initially thought to be safe, but is now recognised as a hazardous and persistent pollutant. It was added to Annex A of the Stockholm Convention on Persistent Organic Pollutants in 2017, which means that treaty members must take measures to eliminate its production and use. The plastics industry started switching to decabromodiphenyl ethane as an alternative in the 1990s, but this is now also coming under regulatory pressure due to concerns over human health.
Pentabromodiphenyl ether is a brominated flame retardant which belongs to the group of polybrominated diphenyl ethers (PBDEs). Because of their toxicity and persistence, their industrial production is to be eliminated under the Stockholm Convention, a treaty to control and phase out major persistent organic pollutants (POP).
Musk xylene is a synthetic musk fragrance which mimics natural musk. It has been used as a perfume fixative in a wide variety of consumer products, and is still used in some cosmetics and fragrances.
A substance of very high concern (SVHC) is a chemical substance concerning which it has been proposed that use within the European Union be subject to authorisation under the REACH Regulation. Indeed, listing of a substance as an SVHC by the European Chemicals Agency (ECHA) is the first step in the procedure for authorisation or restriction of use of a chemical. The first list of SVHCs was published on 28 October 2008 and the list has been updated many times to include new candidates. The most recent update occurred in January 2022 to include a total of 223 SVHC.
A Chemical safety assessment (CSA) is an analysis used in many situations where chemical are used and where there is a possibility that they may present a risk to life, health or the environment.
The Substitute It Now! List is a database developed by the International Chemical Secretariat (ChemSec) of chemicals the uses of which are likely to become legally restricted under EU REACH regulation. The list is being used by public interest groups as a campaign tool to advocate for increasing the pace of implementation of REACH and by commercial interests to identify substances for control in chemicals management programmes.
The substitution of dangerous chemicals in the workplace is the process of replacing chemicals with less hazardous alternatives or eliminating them, generally to improve occupational health and safety or minimize harmful environmental impact. The process can be lengthy, as an assessment of dangers, costs, and practicality is necessary. Substituting hazardous chemicals follows the principles of green chemistry and results in clean technology.
Persistent, bioaccumulative and toxic substances (PBTs) are a class of compounds that have high resistance to degradation from abiotic and biotic factors, high mobility in the environment and high toxicity. Because of these factors PBTs have been observed to have a high order of bioaccumulation and biomagnification, very long retention times in various media, and widespread distribution across the globe. Most PBTs in the environment are either created through industry or are unintentional byproducts.
Cashmeran is a chemical compound used in fragrances.
Tetramethyl acetyloctahydronaphthalenes is a synthetic ketone fragrance also known as OTNE and by other commercial trade names such as: Iso E Super, Iso Gamma Super, Anthamber, Amber Fleur, Boisvelone, Iso Ambois, Amberlan, Iso Velvetone, Orbitone, Amberonne. It is a synthetic woody odorant and is used as a fragrance ingredient in perfumes, laundry products and cosmetics.
Octamethylcyclotetrasiloxane, also called D4, is an organosilicon compound with the formula [(CH3)2SiO]4. It is a colorless viscous liquid. It is a common cyclomethicone. It is widely used in cosmetics.
The GreenScreen for Safer Chemicals is a transparent, open standard for assessing chemical hazard that supports alternatives assessment for toxics use reduction through identifying chemicals of concern and safer alternatives. It is used by researchers, product formulators and certifiers in a variety of industries, including building products, textiles, apparel, and consumer products.
The GreenScreen List Translator is a procedure for assessing chemical hazard used to identify chemicals of concern to prioritize for removal from product formulations. The List Translator assesses substances based on their presence on lists of chemicals associated with human and environmental health hazards issued by a global set of governmental and professional scientific bodies, such as the European Union’s GHS hazard statements and California's Proposition 65.
↑ Ternes, Thomas A; Stüber, Jeannette; Herrmann, Nadine; McDowell, Derek; Ried, Achim; Kampmann, Martin; Teiser, Bernhard (2003). "Ozonation: a tool for removal of pharmaceuticals, contrast media and musk fragrances from wastewater?". Water Research. 37 (8): 1976–82. doi:10.1016/S0043-1354(02)00570-5. PMID12697241.
↑ Baldwin AK, Corsi SR, DeCicco LA, Lenaker PL, Lutz MA, Sullivan DJ and Richards KD. (2016) Organic contaminants in Great Lakes tributaries: Prevalence and potential aquatic toxicity. Science of the Total Environment. 554-555, 42-52. 2016.
↑ Wombacher WD and Hornbuckle KC. (2009) Synthetic Musk Fragrances in a Conventional Drinking Water Treatment Plant with Lime Softening. J Environ Eng (New York). 2009 November 1; 135(11): 1192
↑ Bogdal C, Schmid P, Zennegg M, Anselmettl FS, Scheringer M and Hungerbuhler K. (2009) Blast from the Past: Melting Glaciers as a Relevant Source for Persistent Organic Pollutants. Environmental Science and Technology. Vol. 43, pp: 8173-8177. 2009.
↑ Ramirez AJ, et.al. (2009) Occurrence of Pharmaceuticals and Personal Care Products in Fish: Results of a National Pilot Study in the United States. Environmental Toxicology and Chemistry. Vol. 28, No. 12, pp. 2587-2597. 2009.
↑ Reiner, Jessica L.; Wong, Chung M.; Arcaro, Kathleen F.; Kannan, Kurunthachalam (2007). "Synthetic Musk Fragrances in Human Milk from the United States". Environmental Science & Technology. 41 (11): 3815–20. Bibcode:2007EnST...41.3815R. doi:10.1021/es063088a. PMID17612154.
↑ Hutter H. et.al. (2009) Synthetic musks in blood of healthy young adults: Relationship to cosmetics use. Science of the Total Environment. Vol. 47, pp: 4821-4825. 2009.
↑ Rimkus, G.G. and M. Wolf, Polycyclic musk fragrances in human adipose tissue and human milk. Chemosphere, 1996, 33(10), pages 2033-2043, doi:10.1016/0045-6535(96)00321-9
This page is based on this Wikipedia article Text is available under the CC BY-SA 4.0 license; additional terms may apply. Images, videos and audio are available under their respective licenses.
