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Trace Elements in Abiotic and Biotic Environments
evidence that Ge has any functional role in the body. Inorganic Ge compounds are
readily absorbed and excreted mainly through the kidney, with half-lives in the order
of 1–4 days. When injected intravenously, Ge concentrates in the liver, the kidney,
the spleen, and the gastrointestinal tract. After oral administration, high Ge concentrations were detected in the spleen. Apparently, Ge becomes widely distributed in
the human body after intake or application (Rosenberg 2009).
Limited data on Ge metabolism suggests that organic Ge is thought not to accumulate as inorganic compounds. It is not necessary to human health; however, its
presence in the body has been shown to stimulate metabolism. Germanium may also
play a role in the function of the immune system, immuno-enhancement, oxygen
enrichment, free radical scavenging, analgesia, and metal detoxification. In organic
forms, it is not considered as carcinogenic. Organic Ge appears to inhibit cancer
development and, in the form of the organic compound, spirogermanium, to destroy
cancer cells. Some organic forms of Ge are less toxic, than inorganic ones. Excess
intake of inorganic Ge may adversely affect kidney functioning. Other adverse
effects of Ge are anemia, diarrhea, skin rash, muscle weakness, and peripheral neuropathy. The toxic effects of inorganic Ge compounds usually occurs at its higher
doses (ICL 2011).
Certain compounds of Ge have low toxicity to mammals, but have high toxic
effects against certain bacteria. However, no Ge compound has yet been demonstrated for pharmaceutical use, as either an antibacterial or a cancer chemotherapeutic agent. Some Ge compounds are quite reactive and present an immediate hazard to
human health on exposure. For example, Ge chloride and germane (GeH 4 ) are liquid
and gas, respectively, which can be very irritating to the eyes, skin, lungs, and throat.
Germanium, as an organic complex, has been touted, but not proved, as having
anticancer properties in humans. Inorganic Ge toxicity results in kidney damage.
Some individuals, consuming high amounts of organic Ge supplements contaminated with inorganic Ge, have died from kidney failure.
Ge, although essentially limited in Japan, is used in the production of organogermanium compounds such as Ge sesquioxide, organic Ge or 132 Ge, for medical applications. The interest in Ge sesquioxide was excited and also strongly promoted after
they had screened a large number of Ge compounds for their biological effects. 132 Ge
not only possesses antitumor activity but also increases the production of interferon,
without showing detectable signs of cytotoxicity. Even when used as a food supplement, 132 Ge has been shown to act as an immune stimulant and to enhance the activity of natural killer cells and interferon levels. If adverse effects, and sometimes even
fatal cases, were reported as consequences of treatment with Ge-containing drugs,
this could often be attributed to the ingestion of inorganic Ge, or 132 Ge contamination.
As a consequence, many countries such as the United States and the EU countries
have issued a ban on the import and sale of Ge sesquioxide, as a nutritional additive.
The use of a Ge application in a person who died from acute renal failure resulted in
high Ge concentrations in vertebrae, kidney, brain, and skeletal muscle. This fact has
led to the ban of organogermanium compounds (particularly 132 Ge), as food supplements, due to the possible contamination of organic Ge compounds by GeO 2 from
the manufacturing process, which is still enforced. Hair and nails may be allowed to
monitor excessive Ge uptake (Rosenberg 2009).
Trace Elements in Abiotic and Biotic Environments
evidence that Ge has any functional role in the body. Inorganic Ge compounds are
readily absorbed and excreted mainly through the kidney, with half-lives in the order
of 1–4 days. When injected intravenously, Ge concentrates in the liver, the kidney,
the spleen, and the gastrointestinal tract. After oral administration, high Ge concentrations were detected in the spleen. Apparently, Ge becomes widely distributed in
the human body after intake or application (Rosenberg 2009).
Limited data on Ge metabolism suggests that organic Ge is thought not to accumulate as inorganic compounds. It is not necessary to human health; however, its
presence in the body has been shown to stimulate metabolism. Germanium may also
play a role in the function of the immune system, immuno-enhancement, oxygen
enrichment, free radical scavenging, analgesia, and metal detoxification. In organic
forms, it is not considered as carcinogenic. Organic Ge appears to inhibit cancer
development and, in the form of the organic compound, spirogermanium, to destroy
cancer cells. Some organic forms of Ge are less toxic, than inorganic ones. Excess
intake of inorganic Ge may adversely affect kidney functioning. Other adverse
effects of Ge are anemia, diarrhea, skin rash, muscle weakness, and peripheral neuropathy. The toxic effects of inorganic Ge compounds usually occurs at its higher
doses (ICL 2011).
Certain compounds of Ge have low toxicity to mammals, but have high toxic
effects against certain bacteria. However, no Ge compound has yet been demonstrated for pharmaceutical use, as either an antibacterial or a cancer chemotherapeutic agent. Some Ge compounds are quite reactive and present an immediate hazard to
human health on exposure. For example, Ge chloride and germane (GeH 4 ) are liquid
and gas, respectively, which can be very irritating to the eyes, skin, lungs, and throat.
Germanium, as an organic complex, has been touted, but not proved, as having
anticancer properties in humans. Inorganic Ge toxicity results in kidney damage.
Some individuals, consuming high amounts of organic Ge supplements contaminated with inorganic Ge, have died from kidney failure.
Ge, although essentially limited in Japan, is used in the production of organogermanium compounds such as Ge sesquioxide, organic Ge or 132 Ge, for medical applications. The interest in Ge sesquioxide was excited and also strongly promoted after
they had screened a large number of Ge compounds for their biological effects. 132 Ge
not only possesses antitumor activity but also increases the production of interferon,
without showing detectable signs of cytotoxicity. Even when used as a food supplement, 132 Ge has been shown to act as an immune stimulant and to enhance the activity of natural killer cells and interferon levels. If adverse effects, and sometimes even
fatal cases, were reported as consequences of treatment with Ge-containing drugs,
this could often be attributed to the ingestion of inorganic Ge, or 132 Ge contamination.
As a consequence, many countries such as the United States and the EU countries
have issued a ban on the import and sale of Ge sesquioxide, as a nutritional additive.
The use of a Ge application in a person who died from acute renal failure resulted in
high Ge concentrations in vertebrae, kidney, brain, and skeletal muscle. This fact has
led to the ban of organogermanium compounds (particularly 132 Ge), as food supplements, due to the possible contamination of organic Ge compounds by GeO 2 from
the manufacturing process, which is still enforced. Hair and nails may be allowed to
monitor excessive Ge uptake (Rosenberg 2009).