I recently participated in a thread dealing with this, and I'm glad that the subject of vanadyl sulfate in our supplements, was brought to my attention however.... I wanted to compile all of my information, and present it in a seperate thread (as I feel that it is more appropriately titled, and I am more than willing to confront any company reps on this issue).
It turns out that the majority of companies that are including this substance in their formulations, are doing so, WITHOUT ANY REGUARDS TO TOXICITY.
Taking .5 to 1 mg a day of vanadyl sulfate is enough to meet or exceed nutritional requirements, without risking toxicity. Most of the bodybuilding supplements contain a minimum of 5 mg.... and up to 30 mg!!!!
"High doses of vanadium (anything over 15 mg/day) may cause liver and/or kidney damage."
Taking 0.5 to 1.0 mg/day of vanadium is enough to meet or exceed nutritional requirements, without risking toxicity. No more than 1.8 mg/day should be used in people. Some manufacturers promote high dosages (15 to 100 mg) of vanadyl sulfate per day, but studies do not support such dosages, and they may be toxic. Because the safety and effectiveness of vanadium have not been thoroughly studied, caution should be exercised when using vanadium as a nutritional supplement.
The effects of vanadium have not been studied extensively in people. The majority of studies to date have been conducted in laboratory animals.
Body Building/Performance Enhancement
While vanadyl sulfate is widely used by athletes to enhance performance, beneficial effects have not been confirmed by studies. Use of vanadium is not advised because of the potential toxic effects associated with high doses of this mineral.
Material Safety Data Sheet
MSDS Name: Vanadyl Sulfate
Synonyms: Vanadium, Oxo[sulfato(2-)-O]-; Vanadium, Oxosulfato-; Vanadium Oxide Sulfate; Vanadium Oxylsulfate; Oxo(sulfato)
Warning! Causes eye and skin irritation. Causes digestive and respiratory tract irritation. May cause liver and kidney damage.
Target Organs: Kidneys, liver, respiratory system, eyes, skin.
Ingestion: May cause severe gastrointestinal tract irritation with nausea, vomiting and possible burns. May cause liver and kidney damage. May cause central nervous system effects and/or neurological effects. May cause greenish-black tongue discoloration due to deposition of vanadium salts. Ingestion of large amounts may cause an increase in blood pressure.
Eye: May cause eye irritation and possible damage.
Skin: Contact with skin causes irritation and possible burns, especially if the skin is wet or moist. Contact with the skin may cause skin lesions which are characterized by cracking of the skin and the development of slow-healing ulcers.
Here is more incriminating evidence....
J Inorg Biochem. 1994 Aug 1;55(2):101-12. Links
One-electron reduction of vanadate by ascorbate and related free radical generation at physiological pH.
The one-electron reduction of vanadate (vanadium(V)) by ascorbate and related free radical generation at physiological pH was investigated by ESR and ESR spin trapping. The spin trap used was 5,5-dimethyl-1-pyrroline N-oxide (DMPO). Incubation of vanadium(V) with ascorbate generated significant amounts of vanadium(IV) in phosphate buffer (pH 7.4) but not in sodium cacodylate buffer (pH 7.4) nor in water. The vanadium(IV) yield increased with increasing ascorbate concentration, reaching a maximum at a vanadium(V): ascorbate ratio of 2:1. Addition of formate to the incubation mixture containing vanadium(V), ascorbate, and phosphate generated carboxylate radical (.COO-), indicating the formation of reactive species in the vanadium(V) reduction mechanism. In the presence of H2O2 a mixture of vanadium(V), ascorbate, and phosphate buffer generated hydroxyl radical (.OH) via a Fenton-like reaction (vanadium(IV)+H2O2-->vanadium(V)+.OH+OH-). The .OH yield was favored at relatively low ascorbate concentrations. Omission of phosphate sharply reduced the .OH yield. The vanadium(IV) generated by ascorbate reduction of vanadium(V) in the presence of phosphate was also capable of generating lipid hydroperoxide-derived free radicals from cumene hydroperoxide, a model lipid hydroperoxide. Because of the ubiquitous presence of ascorbate in cellular system at relatively high concentrations, one-electron reduction of vanadium(V) by ascorbate together with phosphate may represent an important vanadium(V) reduction pathway in vivo. The resulting reactive species generated by vanadium(IV) from H2O2 and lipid hydroperoxide via a Fenton-like reaction may play a significant role in the mechanism of vanadium(V)-induced cellular injury.
Oxy-vanadium (IV) complexes having spermicidal activity
Vanadium promotes hydroxyl radical formation by activated human neutrophils
Vanadium Distribution in Rats and DNA Cleavage by Vanadyl Complex: Implication for Vanadium Toxicity and Biological Effects http://links.jstor.org/sici?sici=009...3E2.0.CO%3B2-H
Vanadium(IV)-mediated free radical generation and related 2'-deoxyguanosine hydroxylation and DNA damage http://www.ingentaconnect.com/conten...00001/art03151
Vanadium(IV) causes 2'-deoxyguanosine hydroxylation and deoxyribonucleic acid damage via free radical reactions http://www.annclinlabsci.org/cgi/con...stract/26/1/39