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Updated: May 6, 2026

Quantification of Humic and Fulvic Acids in Humate Ores, DOC, Humified Materials and Humic Substance-Containing Commercial Products
Published on: March 18, 2022
Tissue distribution of absorbed humic acids.
Radioiodinated humic acids (HA) show distinct distribution in rats compared to radioiodine alone. This pattern correlates with organ diseases, suggesting HA-metal complexes as potential etiological factors.
Area of Science:
- Environmental Health
- Toxicology
- Biochemistry
Background:
- Humic acids (HA) are complex organic compounds found in soil and water.
- Epidemiological studies suggest a correlation between exposure to certain environmental factors and increased disease prevalence in endemic areas.
Purpose of the Study:
- To investigate the biodistribution of radioiodinated humic acids (HA) in rats.
- To compare the distribution pattern of HA with that of radioiodine (125I) alone.
- To explore the potential role of HA in the etiology of various organ diseases.
Main Methods:
- Intraperitoneal injection of radioiodinated HA and radioiodine (125I) in rats.
- Measurement of radioactivity distribution in various organs and serum over time.
- Correlation analysis with epidemiological data on disease prevalence.
Main Results:
- The distribution pattern of HA significantly differed from that of 125I.
- 125I was rapidly excreted within 24 hours, except in the thyroid and skin.
- A substantial proportion of HA remained in the liver, kidney, skin, thyroid, bone, and muscle.
- The distribution of HA correlated with increased organ disease prevalence in endemic areas.
Conclusions:
- The distinct biodistribution kinetics of HA compared to free iodine suggest specific interactions within the body.
- HA-metal complexes are hypothesized as potential etiological agents for diseases including goitre, hepatoma, bladder cancer, vascular disease, and diabetes mellitus.
- Free radicals may be a common causative factor in diseases linked to HA exposure.
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