Оксибензон: қасиеттері, қолданылуы және қауіп-қатерлері

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| ImageFile = Oxybenzone. svg
| ImageName = Oxybenzone
| PIN = (2 Hydroxy 4 methoxyphenyl)(phenyl)methanone
| OtherNames = OxybenzoneBenzophenone 32 Hydroxy 4 methoxybenzophenone
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|Section3=Chembox Hazards
| Hazards ref = In nature, oxybenzone can be found in various flowering plants. The compound was first synthesised in Germany by chemists König and Kostanecki in 1906. The use of oxybenzone as sunscreen ingredient is currently under scrutiny by the scientific community due to controversies about its environmental impact and safety profile (see section below). As a result, sunscreens containing oxybenzone have been banned from sale in Hawaii, and Thailand.

Being a conjugated molecule, oxybenzone absorbs light at lower energies than many aromatic molecules. As in related compounds, the hydroxyl group is hydrogen bonded to the ketone. This interaction contributes to oxybenzone's light absorption properties. At low temperatures, however, it is possible to observe both the phosphorescence and the triplet triplet absorption spectrum. At 175 K the triplet lifetime is 24 ns. The short lifetime has been attributed to a fast intramolecular hydrogen transfer between the oxygen of the C=O and the OH.

Oxybenzone is produced by Friedel Crafts reaction of benzoyl chloride with 3 methoxyphenol.

Oxybenzone is used in plastics as an ultraviolet light absorber and stabilizer. Despite its photoprotective qualities, much controversy surrounds oxybenzone because of its possible hormonal and photoallergenic effects, leading many countries to regulate its use.

Oxybenzone provides a broad spectrum ultraviolet coverage which includes UVB and short wave UVA rays. As a photoprotective agent, it has an absorption profile spanning from 270 to 350 nm with absorption peaks at 288 and 350 nm. Due to safety concerns, the percentage of sunscreen products on the market containing oxybenzone in the USA dropped to 13% in 2023 from 60% in 2019. Some brands market their sunscreens as "oxybenzone free" due to the negative perception of benzophenones.

The incidence of oxybenzone causing photoallergy is extremely uncommon, however, oxybenzone has been associated with rare allergic reactions triggered by sun exposure. In a study of 82 patients with photoallergic contact dermatitis, just over one quarter showed photoallergic reactions to oxybenzone. Evidence points to oxybenzone having contact allergen effects. In a 2008 study of participants ages 6 and up, oxybenzone was detected in 96.8% of urine samples. Humans can absorb anywhere from 0.4% to 8.7% of oxybenzone after one topical application of sunscreen, as measured in urine excretions. This number can increase after multiple applications over the same period of time. Because oxybenzone is the least lipophilic of the three most common UV filters, it is the least likely to end up trapped in the stratum corneum and the most likely to be absorbed and metabolized. When applied topically, UV filters, such as oxybenzone, are absorbed through the skin, metabolized, and excreted primarily through the urine. The method of biotransformation, the process by which a foreign compound is chemically transformed to form a metabolite, was determined by Okereke and colleagues through oral and dermal administration of oxybenzone to rats. The scientists analyzed blood, urine, feces, and tissue samples and found three metabolites: 2,4 dihydroxybenzophenone (DHB), 2,2 dihydroxy 4 methoxybenzophenone (DHMB) and 2,3,4 trihydroxybenzophenone (THB). To form DHB the methoxy functional group undergoes O dealkylation; to form THB the same ring is hydroxylated. The major metabolite detected was DHB and very small amounts of THB were found. In 2019, the U. S. Food and Drug Administration (FDA) noted in their recommendations for future study that, "While research indicates that some topical drugs can be absorbed into the body through the skin, this does not mean these drugs are unsafe." Oxybenzone can be found in some plants.

Studies have shown possible links between oxybenzone exposure and mortality in developing coral, coral bleaching, and genetic damage to coral and marine life. However, some of these studies have been criticised for not having control groups or representing real world conditions. Nevertheless, these have led to the ban of oxybenzone containing sunscreen in many areas such as Palau, Hawaii, the Northern Mariana Islands, and Aruba.

As of 2023, the maximum concentration of oxybenzone in a sunscreen cannot exceed 10% according to the TGA (Therapeutic Goods Administration).

Revised as of 2012, Health Canada allows oxybenzone for cosmetic use up to 6%.

The European Food Safety Authority categorises benzophenones, such as oxybenzone, as persistent, bio accumulative, toxic, and a possible human carcinogen and endocrine disruptor. The Scientific Committee on Consumer Products (SCCP) of the European Commission concluded that it poses a significant risk to consumers as a contact allergenic potential. It is allowed in face, hand, and lip products up to 6%, in body products up to 2.2%, and in other formulations up to 0.5%.

Revised as of 2001, the Ministry of Health, Labour, and Welfare notification allows oxybenzone for cosmetic use up to 5%.

The Palau government has signed a law that restricts the sale and use of sunscreen and skincare products that contain oxybenzone, and nine other chemicals. The ban came into force in 2020.

The Swedish Research Council has determined that sunscreens with oxybenzone are unsuitable for use in young children, because children under the age of two years have not fully developed the enzymes that are believed to break it down. No regulations have come of this study yet.

In 2021 the U. S. FDA changed their classification of oxybenzone and no longer regard it as GRASE (Generally Recognised As Safe and Effective) due to the lack of safety data to support the classification. The Hawaii State Legislature has legislated oxybenzone as illegal for use in sunscreens and personal care products since 2021 due to its environmental effects, such as mortality in developing coral, coral bleaching, genetic damage to coral, and other marine organisms. Key West has also banned the sale of sunscreens that contain the ingredients oxybenzone (and octinoxate). The ban was to be effective as of January 1, 2021. However, this legislation was superseded by the Florida State Legislature by Senate Bill 172, which prohibits local governments from regulating over the counter proprietary drugs and cosmetics (such as sunscreen containing oxybenzone and octinoxate). The statute became effective July 1, 2020.