Ethylenediamine Dihydroiodide (EDDI) - CAS 5700-49-2 / Articles

Ethylenediamine Dihydroiodide (EDDI): Properties, Applications, and Safety

Ethylenediamine dihydroiodide (EDDI, CAS 5700-49-2) is a water-soluble organic iodine salt formed by the reaction of ethylenediamine with hydroiodic acid (HI). The compound appears as a colorless to light yellow crystalline powder, with a molecular formula of C₂H₈N₂·2HI (C₂H₁₀I₂N₂) and a molecular weight of approximately 315.92 g/mol. It contains approximately 79.5–80% iodine by weight, making it a highly concentrated and effective iodine source.

Physicochemical Properties

EDDI is characterized by the following properties:

Appearance: White to almost white crystalline powder
Melting Point: Approximately 192°C
Density: ~1.159 g/cm³
Solubility: Highly soluble in water
pH (100 g/L, H₂O, 20°C): 4.0–6.0
Purity: ≥98.0% (typical for reagent grade)
Storage: Store under inert gas, at or below 20°C

Applications

Animal Nutrition (Primary Use): EDDI is widely used as an organic iodine supplement in animal feed, pet food, and salt blocks. It delivers superior bioavailability and stability compared to inorganic iodine sources. Iodine is essential for the synthesis of thyroid hormones (T3 and T4), which regulate metabolism, growth, and reproductive function. EDDI is used to prevent iodine deficiency in livestock, particularly in regions with iodine-deficient soil.

Foot Rot Prevention in Cattle: EDDI has been extensively studied and used as a feed supplement to aid in the prevention of foot rot (interdigital phlegmon) in cattle. Field trials have demonstrated its efficacy in reducing the severity and incidence of the disease. Studies have shown that a dosage rate of 0.11 mg EDDI/kg/day correlates with serum iodine concentrations (20–80 µg/dL) that are effective for foot rot prevention. Recommended continuous use levels are 50 mg/head/day, with treatment levels up to 500 mg/head/day for 10 to 20 days. Supplementation of EDDI (0.156%) in salt-mineral mixes has also been shown to significantly reduce the incidence and severity of foot rot in cattle.

Veterinary Medicine: EDDI is used as an expectorant, anti-inflammatory agent, and treatment for chronic infections.

Chemical and Laboratory Use: EDDI serves as a source of iodine in certain chemical reactions and laboratory applications.

Safety and Toxicology

EDDI is classified as a hazardous substance with the following GHS hazard statements:

H302: Harmful if swallowed
H315: Causes skin irritation
H319: Causes serious eye irritation
H335: May cause respiratory irritation
May cause allergic skin reaction and damage to organs

Although EDDI is generally recognized as safe (GRAS) as a nutrient source of iodine, excessive intake can lead to iodine toxicity (iodism). Cattle may overeat EDDI-treated mineral supplements, producing milk with excess iodine. EDDI may react with sulfates and release free iodine. Appropriate personal protective equipment (gloves, safety goggles) should be used when handling the compound.

Regulatory Status

EDDI is listed as a synthetic feed additive by the Association of American Feed Control Officials (AAFCO). It is approved for use in animal feed in many countries and is available in feed-grade formulations.

Storage and Handling

EDDI should be stored in tightly sealed containers under inert gas, at or below 20°C. It should be kept in a cool, dry place, protected from moisture and light. The compound should be stored away from strong oxidizing agents and acids.

Conclusion

Ethylenediamine dihydroiodide (EDDI, CAS 5700-49-2) is a highly concentrated, water-soluble organic iodine source widely used in animal nutrition and veterinary medicine. Its high iodine content (approximately 80%), excellent bioavailability, and efficacy in preventing iodine deficiency and foot rot in cattle make it a valuable feed additive. However, its classification as a harmful and irritant substance necessitates proper handling, storage, and adherence to recommended dosage levels to avoid toxicity and adverse effects.