Germanium Sesquioxide
Organic Germanium

Bis (2-Carboxyethylgermanium)sesquioxide

Demonstrated Safety of Germanium Sesquioxide

The low toxicity of pure germanium sesquioxide is well supported by both animal and human studies. Scientific data demonstrates a margin of safety difficult to surpass with both acute and chronic exposure through various routes of administration.

A 1991 study conducted on Wistar rats demonstrated no toxic effects or renal histological abnormalities with 120 mg/kg/day of germanium sesquioxide over a 24 week period. Germanium sesquioxide did not concentrate selectively in any particular organ and was virtually all excreted unchanged via urine within 72 hours. In contrast, this same study showed that 75 mg/kg/day of GeO2 caused weight loss, elevated blood urea, renal compromise i.e. tubular atrophy and vacuolar degeneration. The conclusion of this study was that germanium sesquioxide exhibited extremely low toxicity.

Another rat study in 1992 reported no discernable toxic symptoms following a six month chronic dose of 1,000 mg/kg/day.

An animal study conducted in 1997 demonstrated that germanium sesquioxide is rapidly removed from plasma and does not accumulate in tissues.
Gerber GB, Leonard A. Mutagenicity, carcinogenicity and teratogenicity of germanium compounds. Mutation Research 1997;387(3):141-146.

Low toxicity for germanium sesquioxide exposure is further substantiated through human studies. Dosages of 25, 50, and 75 mg/kg were administered to 20 healthy volunteers. Routes of administration were varied as well as the duration of exposure. No unusual reactions, blood or urine values were observed. This study elevated gamma interferon production in a dose dependant fashion for 90% of test subjects. Rapid elimination from the body was also noted with 80% being excreted unchanged in the first 9 hours following administration7.

A critical observation in regards to the general toxicity of all substances was made by Paracelsus (1493-1541) over 500 years ago: "All substances are poisonous; there is none which is not a poison. The right dose differentiates a poison and a remedy." The wisdom of this statement is irrefutable when we consider that even pure water in sufficient quantity will kill. Once we accept this fact, it makes perfect sense to compare one substance to others thereby establishing a “relative” measurement of toxicity. This is precisely what led to the concept of LD50.

LD50 is the “Lethal Dose” of any given material required to kill 50% of a given population. LD50 data is typically stated in a dosage amount per every kg of body weight of a test subject. By this criterion, highly toxic materials always have a lower LD50 than less toxic materials. For obvious reasons, most LD50 data on any substance is collected from animal and not human testing. In spite of this, LD50 has proven quite reliable when extrapolating to human toxicity, and always provides a good point of reference. Published LD50 data for germanium sesquioxide is further evidence of its safety.

The reported LD50 for germanium sesquioxide is in excess of 6,300 mg/kg orally for mice, greater than 10,000 mg/kg orally for rats, and greater than 1,000 mg/kg intravenously for rats. Chronic exposure studies are equally impressive at 3,000 mg/kg orally for 6 months on rats with no toxicity, and 500 mg/kg intravenously for 6 months on dogs, also with no toxicity. Considering this data in its proper perspective, germanium sesquioxide is at least 1 (one) time safer than calcium carbonate 47, three (3) times safer than table salt 48, four (4) times safer than potassium chloride 48, and 23 times safer than chromium picolinate 49. "Safer Than Table Salt Article".

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