Does anyone have any info on the safety of using Vanadium in glazes. I have a green glaze formula (below) that I would really like to try, but Vanadium is one of those ingredients that is listed in the "toxic elements" list.
I teach adult community education, so I mix glazes in mass amounts. In addition, my students and I dip pottery in the glazes without any protective wear. I try not to kill my students.
Any info would be appreciated.
Cone 10 Redux
Nepheline Syenite 31
China Clay 12
Copper Oxide 2
Venadium Pentoxide 8
Look what I found on the OSHA website right next to the bright red skull and crossbones:
1. Conditions contributing to instability: Heat. (In other words, it is most dangerous while in the kiln)
2. Incompatibilities: Contact of vanadium pentoxide with chlorine trifluoride, ***LITHIUM***, or peroxyformic acid causes a violent reaction, and the dust is also likely to be incompatible with these substances.
3. Hazardous decomposition products: Toxic dusts (such as vanadium oxides) may be released when vanadium pentoxide is heated to decomposition.
Effects on Humans: Vanadium pentoxide dust irritates the mucous membranes of the upper respiratory tract, bronchi, lungs, eyes, and skin of exposed humans. Acute intoxication may cause systemic symptoms, and repeated exposure may lead to chronic bronchitis.
Effects on Animals: Vanadium pentoxide dust irritates the eyes, mucous membranes, and respiratory tract and may cause nervous system, gastrointestinal tract, liver, and kidney damage in laboratory animals. The oral LD(50) for rats is 10 mg/kg; the lowest lethal concentration by inhalation in the same species is 70 mg/m(3) for 2 hours [RTECS 1989]. Acutely poisoned animals develop nose bleeds, labored respiration, diarrhea, hind limb paralysis, and seizures [Gosselin, Smith, and Hodge 1984, p. II-148]. At autopsy, the pathologic lesions seen in these animals included desquamative enteritis; vascular congestion of the liver, kidneys, lungs, adrenal glands, brain, spinal cord, and bone marrow; and fatty degeneration of the liver and kidneys [Gosselin, Smith, and Hodge 1984, p. II-149]. Rabbits exposed once for 7 hours to a vanadium pentoxide concentration of 205 mg/m(3) died of pulmonary edema (Clayton and Clayton 1981, p. 2020). Dogs, rabbits, guinea pigs, and rats exposed to a 0.5-mg/m(3) concentration of vanadium pentoxide dust for 6 hours/day for 6 months exhibited no signs of toxicity and showed no pathologic changes at autopsy (Clayton and Clayton 1981, p. 2021). Laboratory animals fed 5 percent vanadium pentoxide in their drinking water daily developed anorexia and died within 10 weeks (HSDB 1985). Intravenous administration of 10,900 mg/kg vanadium pentoxide to mice on day 8 of pregnancy induced musculoskeletal abnormalities in their offspring [RTECS 1989].
PERSONAL HYGIENE PROCEDURES
If vanadium pentoxide dust contacts the skin, workers should immediately wash the affected areas with soap and water.
Clothing contaminated with vanadium pentoxide dust should be removed immediately, and provisions should be made for the safe removal of the chemical from the clothing. Persons laundering the clothes should be informed of the hazardous properties of vanadium pentoxide dust, particularly its potential to be irritating to the eyes and upper respiratory tract.
A worker who comes in contact with vanadium pentoxide dust should thoroughly wash hands, forearms, and face with soap and water before eating, using tobacco products, or using toilet facilities.
Workers should not eat, drink, or use tobacco products in areas where vanadium pentoxide dust is generated.
For more info see: http://web.archive.org/web/20060722042705/http://www.osha.gov/SLTC/healthguidelines
If someone knows of a chemical safety site directly for potters, please post it. Knowing a danger of vanadium is high temperatures answers some questions, but if the only danger is a temporary cough, the problem is different than "the danger is death".