Musk

Almizcle gel obtained from an almizclero deer

The term musk or musco (from the Latin muscus) is the name originally given to a perfume obtained from a strong-smelling substance, secreted by a musk deer gland, and then applied to substances produced by other animals and plants that have a similar odor.

Etymology

Musk derives from the Hispanic Arabic almísk, the latter from Classical Arabic misk, and the latter from the pelvi mušk.

For its part, the word musco entered the Spanish language in 1734 and derives from the Latin muscus, which in turn originated from the late Greek μόσχος (mósjos), from Persian mushk, similar to Sanskrit मुष्क muṣka ('testicle'), derived from the Proto-Indo-European noun múh₂s, meaning 'mouse', which shares the same etymology as the word muscle or the English mouse (mouse), common in most European languages.

Natural musks

The variety that is marketed is the secretion of the musk deer. The scent is also found in the musk monkey (also called the machango or brown monkey), the musk ox, the muskrat of India and Europe, the musk duck (Biziura lobata) of southern Australia, the musk shrew, the musk beetle (Calichroma moschata), the Central American alligator and other animals.

In the plant kingdom, it is found in the common musk (Mimulus inoschalus), in the muskwood of the Guianas, and in the seeds of the Hibiscus abelmoschus Abelmoschus moschatus musk seeds Ambrette.

To obtain musk deer perfume, the animal is killed and the gland is completely removed, leaving it to dry, either in the sun, on a hot stone, or by immersing it in hot oil. In perfumery, it is common to call musk with the English word musk (for this reason its main chemical component is called muscone); thus it is marketed as musk in pod (the whole gland) or as musk in grain (where the perfume has been extracted from its receptacle). It should be taken into account that the musk or pure musk has a very intense odor almost unbearable for the human nose, for this reason the musk or musk is applied in very small doses to perfumes, it is considered that such perfumes are exciting since they have pheromone-type molecules.

Three types are known:

1. Tong-king, Chinese or Tibetan, imported from China, the most valuable;
2. Assam or Nepali, less valuable;
3. Karbardino or Russian (Siberian), imported from Central Asia through Russia, the least valuable.

Tong-king musk is exported in small containers richly decorated with tin or lead filigree, where the perfume is sealed; it is sent directly to the merchant by mail.

The musk is dark purple in color, dry, smooth and oily to the touch, and bitter to the taste. In addition to its odoriferous principles, it contains ammonia, cholesterol, fat, and other animal principles. As a raw material in perfumery, it is of the greatest importance, giving strength and permanence to plant essences with its powerful and long-lasting scent, thus being an ingredient in many compound perfumes.

Numerous products have been synthesized that secrete aromas similar to the natural one. The first of all was obtained by Baur in 1888 by condensing toluene with isobutyl bromide in the presence of aluminum chloride, and subsequently nitrating the product thus obtained. It is a tert-butylnitrotoluene. Many similar formulas have been created, and it is observed that the odor depends on the isomer or mixture of isomers obtained.

Synthetic musks

Known as white musks, they are synthetic scent chemicals that mimic the smell of natural musks, obtained from musk deer or civet. Unlike these, synthetics provide a soft and sweet clean smell, since it suppresses the characteristic connotation of the animal. Synthetic musks are cheap and easy to produce fragrances that are mainly added to personal care and household cleaning products..

Classification

Nitrogenous or nitro-musks

Synthetic musks, obtained by Albert Baur in 1888 by condensation of toluene with isobutyl bromide in the presence of aluminum chloride, and the nitration product. They are substances that are highly soluble in organic solvents, are lipophilic, and persistent in adipose tissue. They present high chemical stability, low biodegradability and high bioaccumulation potential. The use of some of them is limited, because they are in studies due to suspicions of inducing cancer or increasing the carcinogenic effect of other compounds. Their production today, it has decreased due to its toxicity both in man and in the environment.

Polycyclics

Group of synthetic musks, which appear due to the need to eliminate the nitro functional group of nitro-musks. Said functional group presents high photochemical reactivity and is unstable in an alkaline medium. They are substances whose main structure is the indane or tetralin molecule with numerous substitutions. The characteristics of this group is that they are highly soluble substances in organic solvents, are lipophilic and persistent in adipose tissue. They have high chemical stability, low biodegradability, and high bioaccumulation potential. They have been detected in breast milk, blood, and newborns.

Macrocyclics

Group composed of a set of synthetic and natural musks. All of them come from natural musk. They are macrolide ketones (animal origin), lactones and bis-lactones (vegetable origin) They have a high production price, despite the fact that their production is easy, since it is a microbial decomposition of the same, thus affecting the stability of this group, and present greater biodegradation than the two previous groups. They provide an important advantage, and that is that despite being synthetic, it is the group that is least harmful to health and the environment.

Applications

The main route of contact is the dermal route, or direct inhalation.

• Perfumes
• Medicine
• Champus
• Detergents
• Soft
• Lotions
• Soaps
• Cleaning products
• Ambients
• Tobacco
• Herbicity
• Explosives
• Fishing stocks
• Hand cream
• Food
• Incense sticks

Toxicity

Synthetic musks have a low rate of biological and chemical degradation and are highly lipophilic compounds, so they can be considered potential environmental pollutants.

In the eighties, the presence of nitro-musks was detected for the first time in biological samples and river water. These compounds have been found in different environmental samples, waste and surface water, aquatic animals, marine mammals and even in samples of human origin such as breast milk or adipose tissue.

Nitro-musks are used in industry, and both they and their metabolites have been found in higher concentrations in the environment. The metabolites are usually more toxic, due to the reduction of the nitro groups to amines.

The use of ambrette musk has been prohibited in Europe since 1995, due to its photoallergenic action, which can be harmful to human health, we could find it in cosmetic products. In 1998, Moskene and Tibetene musks were withdrawn due to their long-term toxicity.

In a study on the bioaccumulation of polycyclic musks and nitro-musks in wastewater aquatic biota, it was determined that the bioaccumulation factors in these species depend on a base lipid (BAFL) and emphasizing that their metabolism should not be neglected.

These compounds are partially eliminated during wastewater treatment, but the problem is their accumulation in sewage plant sludge, which will be used as fertilizer in the fields, potentially contaminating surface water and food.

There is information on the monitoring of these compounds in the environment but the route of elimination has been studied very little, it could be photodegradation.

Polycyclic musks are the ones that are produced in the greatest amount in industries and also have a high lipophilic character, which is why they are mostly detected in the environment and mainly in wastewater sludge. A study conducted on polycyclic musks in wastewater indicates the possibility of adverse effects on the organisms studied (larvae and freshwater mussel) after long exposure to synthetic musks.

Two reports on galoxide and tonalide conclude that there is no significant risk to human health, exposure by different routes of these two compounds. But the Scientific Committee on cosmetic products and non-food products states that no more than 12% of tonalide can be incorporated into fragrances. Reduction of these compounds in the environment could be achieved through photochemical degradation.

Most health impact studies are done with musk xylene and musk ketone. Both have estrogenic activity in vitro, although musk xylene shows three times greater affinity for the estrogen receptor, also increases its potency when metabolized, while musk ketone loses activity when metabolized. Polycyclic musks are selective estrogen receptor modulators and induce both estrogenic (higher doses) and antiestrogenic (lower doses) activities.

A human study has shown a significant relationship between blood musk xylene and musk ketone levels and some hormonal and gynecological problems in women, suggesting that these musks cause reproductive and endocrine toxicity in humans.

In a study on the toxicity/carcinogenicity of musk xylene in mice, results showed that it is carcinogenic in mice at 80-week (long-term) administrations. Musk xylene cannot be listed as a human carcinogen, but is laboratory animals, therefore it belongs to category 3; and is classified as a very toxic compound for aquatic organisms by the European Commission. Musk ketone has a very similar structure and is therefore classified in the same way, although studies on its carcinogenicity have not been performed.

Current use

Currently, the use of natural musks is almost non-existent due to animal protection. Many of the nitro-musks and polycyclics have been banned in Europe due to their environmental and human toxicity. These two groups have seen their consumption reduced because they persist in the environment and break down very slowly. However, macrocyclicals have seen their consumption increase.