# Potential Possibilities of Using Peat, Humic Substances, and Sulfurous Waters in Cosmetology
## 3 Peat
### Peat Composition  
In terms of chemical composition, peat is a mixture of organic compounds, mineral substances, and water. There are two processes that influence the composition and properties of peat. The first is humification, in which decomposition occurs and the formation of the humic compounds' characteristic of peat deposits occurs. The second is during mineralization, which involves the decomposition of organic substances to produce mineral compounds (carbon dioxide, ammonia, phosphate, or sulfate ions) [32].  
The carbon content in various types of peat is 50-60% dry matter and is increasing with the degree of its decomposition. The oxygen content in peat is 33-40% dry weight (DW) and is higher for low-moor sphagnum peat. Knowledge about the oxygen and carbon contents allows us to determine the degree of mud decomposition and its age. The hydrogen content in peat is approximately 6% of DW. It is found in peaks approx. 0.5-4.0% of DW nitrogen, which occurs mainly in an organic form, and 0.1-1% of DW sulfur [34]. Table 3 shows the chemical composition of the peat [10].  
Humic compounds (mainly humic acids, fulvic acids, and humins) are the most important organic compounds found in peat as a source of energy, carbon, and nitrogen for soil microorganisms and plants. They are polymers with high molecular weight and diverse structures. They are rare in unbound soil and are usually bound to minerals to form salts of humic compounds (fulvine acids, humates), humic complexes and intra-complex compounds (chelates), and combinations of humic compounds with clay minerals [10]. A high content of humic compounds occurs primarily in humus soil, peat, and sapropel [35]. Their chemical form is influenced by, among others, conditions in which the process of  
peating (humification) of plants takes place and their type, duration of humification, and hydration of the local environment [36]  
Humic acids (10-43%) are considered the most important biologically active constituents of peat. Because of the diversity and variability of humic acids, it is not possible to establish a clear structure. These are high-molecular-weight compounds consisting of an aromatic core connected by bonds with amino acids, sugars, peptides, aliphatic acids, and other ingredients with an aliphatic structure. The core consists of aromatic rings of the phenol type or containing cyclic compounds' nitrogen. Reactive groups are an important element of the structure of molecules, such as the carboxyl (-COOH), methoxy (-OCH\({}_{3}\)), carbonyl (O=C\(<\)), hydroxyl (-OH), and quinone groups [37].  
Peats also contain yellow-brown fulvic acids (5.5-25%), soluble in water over the entire pH range. They are compounds with a lower molecular weight and a larger number of aliphatic groups compared to humic acids. Obtained from low-moor sphagnum peat, they are characterized by a lower carbon content, the number of carboxyl and phenolic groups, and more hydrogen, nitrogen, oxygen, and methoxy groups than fulvic acids from high-moor sphagnum peat. Their content decreases with an increasing peat depth  
Peat is also a source of slightly soluble bitumens (7-22%), which do not improve the soil structure but give it a more hydrophobic character. This group of compounds includes waves and tars. Bitumen content in peat increases with age, depth of the deposit, and the degree of humification. The least researched humic substances, non-participating in soil transformation processes, include humins characterized by a black color and insolubility over the entire pH range [38].