Humic Acid Waters

Most organic matter in natural waters and soils consists of humic substances: the mostly stable (or refractory) component that remains after the incomplete decomposition of plants and bacteria. There are three products that result when humic substances are extracted with an aqueous base. These include:

1. the non-extractable material called ‘humin’;
2. ‘fulvic acids’; and
3. ‘humic acids’.

The humic and and fulvic acids can form complexes with metals. At very low pH (less than 3) the humic acid-metal complexes may precipitate.