Humic Substances

Humic substances are dark-colored, amorphous, acidic, hydrophilic, partly aromatic and chemically-complex organic heteropolymers found in coal, peat, and soils. They typically constitute 65 to 75% of the organic matter of most predominantly-inorganic soils. These substances are relatively resistant to microbial degradation and have the ability to form water-soluble and water-insoluble complexes with metal ions and hydrous oxides. These substances also interact with minerals and a wide variety of organic compounds, including alkanes, fatty acids, dialkyl phthalates, pesticides, herbicides, carbohydrates, amino acids, peptides, and proteins. Through these interactions, humic substances exert a significant influence on physical, chemical, and biological soil processes.

Because of the characteristics of humic substances, they are of interest to scientists in a wide variety of disciplines. EarthFax Development is pleased to assist these scientists by offering services to extract, purify, and characterize humic substances in solid and liquid media.

Characteristics and Uses

Humic substances are divided into three crude fractions based on their solubilities in aqueous bases and acids.

Laboratory Procedures

EarthFax employs procedures for humic substance extraction and purification which were adapted from methods developed by the International Humic Substances Society (IHSS).

Sample Requirements and Price List

Field samples (both solid and liquid) should be placed in sturdy containers and labeled with a water-proof marker to indicate the sample identification.