# Potential Possibilities of Using Peat, Humic Substances, and Sulfurous Waters in Cosmetology
## 3 Peat
### Potential Uses of Peat and Humic Compounds
#### Humic Compounds in Cosmetics  
Humic acids are used in clinical practice, dermatology, but also increasingly in cosmology [61]. It has been shown that substances with low molecular weight (<1000 Da), mainly humic acids, are responsible for the stimulating effect of peat on the skin [82].  
The basic parameter influencing the effectiveness of peat in cosmetics and treatments is the processing of the raw material, for example, the method of extraction of humic compounds. A great difficulty and challenge for scientists is the extraction process of these compounds, which is time consuming, expensive, and difficult to reproduce [14]. While in the case of a treatment such as a bath or compress, the type of peat (its chemical composition), the treatment time, and the temperature of the raw material are the most important, in the case of using the peat in a cosmetic preparation, the most important thing is the processing, which allows for the isolation of active substances, mainly humic compounds [39; 82; 83].  
Humic substances have astringent and anti-inflammatory properties; therefore, they have the potential to be used in skin diseases such as atopic dermatitis, cheiropodopompholyx, psoriasis, and mild focal hyperhidrosis [61]. They may also be used in rosacea due to their ability to reduce redness and inflammation [84; 85]. The photoprotective properties of humic acids have also been demonstrated. The behavior of _Escherichia coli_ immersed in water systems enriched with humic acids was studied under the conditions of PAR, UV-A, UV-B, and simulated solar radiation. The protection provided by humic acids against light radiation is probably due to their ability to absorb this radiation and thus reduce the amount of energy reaching cells. This phenomenon can be used in the production of photoprotective cosmetics [86].  
The [PERSON] and [PERSON] study [87] demonstrated the ability of humic substances of a natural origin to reduce surface tension, while industrially produced humic materials had no or only a very slight effect on surface tension. This phenomenon can be used in various industries, including consmetology, especially in the production of cleansing cosmetics.  
[PERSON] et al. [88] patented in 2015 a complex combining ethanolic peat extract with isolated humic acids. The obtained complex exhibited antioxidant activity and the ability to promote skin cell proliferation, which makes it a potential ingredient of anti-aging cosmetics. Also, the content of antioxidant substances (such as phenolic acids and flavonoids) and, therefore, the anti-free radical effect depends on the peat extraction method [59].  
The invention of [PERSON] et al. [89] relates to a method of extract composition control in peat extraction by carbon dioxide, in which method the extraction temperature is 5-120 \({}^{\circ}\)C, pressure is 70-1000 bar, and the extraction is conducted in the presence of a modifier. The invention also relates to a peat extract comprising sterols and use of it in skin care or keratin fiber care products, general hygiene products and/or cosmetic products.