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Cosmetic Peat
Association

Bioactive Substances

The chemical compounds in peat responsible for its therapeutic and cosmetic effects.

16 substances 5 humic substances 4 minerals 3 phenolic compounds 3 other compounds 1 materials

Humic Substances

5 substances

Fulvic Acids

The smallest, most bioavailable fraction of humic substances — soluble at any pH and shown to cross the skin barrier, carrying minerals with it.

1,000–10,000 Da · 5–20% of dry mass, higher ratio in sphagnum peat

Humic Acids

Peat's primary bioactive compound — large, dark molecules with anti-inflammatory, antimicrobial, and antioxidant effects working through several pathways at once.

10,000–100,000+ Da · 10–40% of dry mass

Humin

The insoluble structural fraction of peat — holds heat and water rather than acting as a chemical, but makes whole-peat treatments physically work.

>100,000 Da · 20–50% of dry mass

Hymatomelanic Acids

An ethanol-soluble subfraction of humic acids, unusually well-characterized in Estonian peat, with receptor-level activity linked to muscle relaxation.

Present alongside humic acids — separated by ethanol extraction

Ulmic Acids

A low-molecular-weight fraction that helped prove peat's chemical effect is real — permeated fractions were shown to act on receptors on the far side of human skin.

<1000 Da (low molecular weight fraction) · Present in aqueous peat extracts alongside fulvic acids

Minerals

4 substances

Iron

Peat's most abundant mineral, chelated by humic and fulvic acids so it stays bioavailable for collagen synthesis without becoming a pro-oxidant.

55.85 Da · 0.1–2% of dry mass, highly variable by source

Magnesium

A mineral involved in muscle relaxation and inflammatory regulation, absorbed transdermally during peat bath immersion.

24.31 Da · 100–5000 ppm, higher in lowland peat

Sulfur Compounds

One of dermatology's oldest remedies — present in peat as both mineral and organic sulfur, with keratolytic and antimicrobial effects.

32.06 Da · 0.1–2% of dry mass

Zinc

An essential trace mineral for cell division, wound repair, and antimicrobial defence, delivered transdermally when chelated by fulvic acids.

65.38 Da · 10–200 ppm, variable by source

Phenolic Compounds

3 substances

Phenolic Compounds

A broad class of antioxidant, antimicrobial, and astringent aromatic compounds — the same chemistry that lets bogs preserve 2,000-year-old bodies.

Varies widely — 100 to 10,000+ Da · 1–10% of dry mass

Sphagnol

A historic antimicrobial phenolic from sphagnum moss, used as a field antiseptic in WWI wound dressings before antibiotics existed.

Trace — primarily in fresh or lightly decomposed sphagnum peat

Tannins

Astringent phenolic compounds that tighten skin on contact and suppress microbes — the same chemistry behind bog-body preservation and leather tanning.

500–20,000 Da · Variable — higher in less decomposed sphagnum peat

Other Compounds

3 substances

Organic Acids

Small water-soluble acids — citric, malic, oxalic and others — that keep peat naturally acidic and provide gentle AHA-like exfoliation.

60–200 Da (small organic acids) · 0.5–3% of dry mass

Polysaccharides

Large, water-holding sugar molecules including sphagnan, a uniquely antimicrobial polysaccharide found only in sphagnum moss.

Varies — 10,000 to 1,000,000+ Da · 5–15% of dry mass, decreasing with humification

Waxes and Lipids

Hydrophobic compounds from decomposed plant cell walls that soften skin and seal in moisture as part of peat's triple moisturizing mechanism.

Varies · 1–8% of dry mass

Materials

1 substance

Peat

The organic sediment itself — a concentrated, synergistic system of humic substances, minerals, polysaccharides, and lipids formed over millennia in waterlogged bogs.