Palladium is a silver-white ductile and malleable metal that belongs to the platinum group. William Hyde Wollaston discovered palladium in 1803 in crude platinum ore from South America. Palladium is also found in the platinum mines of Russia, Canada and Columbia. Palladium has a very similar chemistry to that of platinum. Since its discovery, palladium has been found to have no biological role.
At one time, palladium chloride was formerly prescribed as a treatment for tuberculosis at the rate of 0.065 g per day (approximately 1 mg kg-1), but fell out of use due to its side effects.
In dentistry, palladium is a very common component of dental casting alloys of all types, and its use has increased over the past several decades in response to the increased cost of gold. However, current research has demonstrated that palladium as used in dentistry is biologically toxic and poses a health risk. Since 1993, the German Health Ministry has warned dentists not to use palladium-copper alloys. In Switzerland, palladium dental alloys have been banned. The carcinogenic potential of the palladium ion is still unclear, although there is some evidence that it is capable of acting as a mutagen.
The use of gold in dentistry dates to ancient times and, today, the gold used by most dentists contains dangerous amounts of palladium. German biological medical doctors refer to palladium/gold alloy as the “fool's gold” of dentistry, because it may be more dangerous than mercury. The amount of palladium used today in making dental crowns and bridges varies considerably, whereas gold restorations may contain up to 78.5% of other dangerous heavy metals.
Atomic mass: 106.42
Sources of Exposure
Palladium is primarily used in industry in electrical contacts as a catalyst, used to purify hydrogen gas, used in dentistry (as an alloy in gold crowns and bridges), used in fine instruments such as watches and some surgical instruments, and used in making jewelry and coinage. Pd has also been used as a radioactive isotope in the treatment of rapidly growing, high-grade prostate cancer. To date, the most identified sources of palladium exposure for the general population are dental restorations. In dentistry, palladium, gold, titanium, mercury, silver, tin, nickel, platinum, and rhodium, are still used in the production of various dental fillings.
Like mercury, Pd is cytotoxic and kills or damages cells. Palladium also causes considerable damage and degradation of DNA and exacerbates hydroxyl radical damage. Palladium also damages cell mitochondria and inhibits enzyme activity and function. Tests in Germany showed the following toxic effects of palladium:
Obstruction of important enzyme systems like creatin-linase, aldolase, alcalite phospatase, carbon-anhydrease, trypsin, chymotropsin, cellulase
Disturbance of collagen synthesis like bone and cartilage
Obstruction of thymidin in the DNA
Accumulation in body organs
Allergic reactions, especially for people with nickel allergies
Information on the elimination and excretion of Pd is scarce and refers mostly to palladium chloride and sodium tetrachloropalladate, which are eliminated in feces and urine. Urinary excretion rates of intravenously dosed rats and rabbits ranged from 6.4 to 76% of the administered dose over a time range of 3 h to 7 days. The elimination of palladium in feces ranged in these studies from traces up to 13% of the administered dose. Following oral administration of palladium chloride, >95% of palladium was eliminated in feces of rats due to non-absorption. Subcutaneous or topical treatment with palladium sulfate (PdSO4) or other palladium compounds resulted in detectable concentrations of Pd in the urine of guinea pigs and rabbits.
Half-lives calculated for the elimination of Pd from rats (whole body, liver, and kidney) ranged from 5 to 12 days.
The Pd cations in dental alloys are continuously released and accumulate in the kidneys, liver, thyroid, brain, and CNS. The gold/palladium alloys in proximity to mercury/silver alloys create high levels of galvanic current densities. This causes extensive migration of mercury and palladium to saliva, tooth roots, jaw, gums, and other parts of the body.
Early symptoms of toxicity due to Pd dental crowns or bridges include: increased salivation, pain in teeth and jaw, burning tongue, metallic taste, peeling of mucous membrane around teeth, fungus-like coating in throat (thrush) and frequent sore throats, and painful, swollen lymph nodes in the neck.
Late symptoms of Pd toxicity include: teeth pulp death, granulomas, puss pockets with dead tissue, swollen tongue; nerve pain in the face; paralysis of face; muscle cramps of tongue, lips, around eyes; sinus infection, bronchitis and lung ailments without clear reason; difficulty breathing at night; problems with stomach, intestines, liver, bladder, kidneys; weight loss; joint and muscle pain; muscle cramps and weakness; tinnitus; visual disturbance; depression, insomnia; outbreaks of sweat, palpitations, difficulty concentrating.
Tumors associated with Pd exposure have been reported in two studies. Mice given palladium chloride (5 mg Pd2+/litre) in drinking-water from weaning until natural death developed malignant tumors, mainly lymphoma-leukemia types and adenocarcinoma of the lung, at a statistically significant rate, but concomitant with an increased longevity in males, which may explain at least in part the increased tumor rate. Tumors were found at the implantation site in 7 of 14 rats (it was not clear whether the tumors were due to the chronic physical stimulus or to the chemical components) 504 days after subcutaneous implantation of a silver-palladium-gold alloy. No carcinogenicity study with inhalation exposure was available.
Transfer of small amounts of Pd to offspring via placenta and milk was seen with single intravenous doses of palladium (II) chloride in rats.
Significant immune responses have been obtained with palladium chloride and/or chloropalladates using the popliteal and auricular lymph node assay in BALB/c mice. Preliminary data in an animal model suggest that Pd compounds may be involved in induction of autoimmune diseases.
Signs & Symptoms
Nutrients Known to be Protective Against Palladium
Owing to the ability of palladium ions to form binding complexes to proteins and amino acids, the following sulfur-bearing amino acids N-acetyl cystine, L-methionine are useful chelating agents. In addition, certain algae (laminaria, fucus, chlorella), vitamin C, selenium, and alpha lipoic acid are all antagonistic for reuptake and retention of palladium.
Protocols for Palladium Detoxification
Palladium detoxification is like detoxification for mercury. The following may serve as a basic guideline for detoxification of excess palladium from chronic exposure. After 60 days, laboratory screening should be used to reassess protocol. Before initiating a detoxification program, a CBC with chemistry, including a thyroid panel with lipids should be performed. In addition, whole blood elements to assess the mineral status and a urine creatinine clearance should be performed every 60 days when using synthetic detoxifying agents. Administration of glycine and synthetic agents may cause a depletion of essential elements such as zinc, iron, calcium, magnesium, copper and other trace minerals. Of greatest concern is potential kidney toxicity that can occur when the body releases its palladium stores for excretion through the kidneys. Those with underlying kidney disease may not be able to undergo aggressive palladium detoxification therapy.
First, identify the source of palladium (usually gold alloy dental restorations) and remove it. Though the International Academy of Oral Medicine and Toxicology (IAOMT) does not have a specific protocol for palladium removal, their “SMART” mercury removal protocol may be used as a substitute.
Assess whole blood cell element analysis to determine mineral nutrient deficiency and supplement appropriately.
Supplement 200 mcg of selenium daily.
Supplement buffered vitamin C (corn free source) at 2000 mg up to 5000 mg daily adjusting to bowel tolerance.
Supplement vitamin E at 400 to 800 IU daily.
Supplement Alpha Lipoic Acid at 250 mg twice daily.
Algal cells have a remarkable ability to take up and accumulate heavy metals from their external environment. The primary ones used for toxic metal excess is Chlorella vulgaris, a green microalga, and Laminaria japonica, a brown alga. Chlorella and Laminaria japonica are both chelators, moving toxic metals out of the body, and transporters, moving metals from deeper stores to more readily removable areas. Both work in unison with each other and can remove toxic metals from the body through urinary excretion. Administer 1000 to 2000 mg of Laminaria japonica concentrate (Modifilan) daily and 1000 to 2000 mg of chlorella. Adjust dosage to bowel tolerance; may be taken for long periods of time.
Shilajit is an ancient traditional medicine (Tibetan and Ayurvedic) and has been ascribed a number of pharmacological activities and has been used for ages as a rejuvenator and for treating a number of disease conditions. It is an effective detoxifier of metals and contains over 60 minerals. Modern scientific research has systematically validated a number of properties of shilajit and has proven that shilajit is truly a panacea. It is important to purchase the highest grade of shilajit.
There is clinical evidence that DMPS is a useful chelator for palladium. DMPS is usually administered by slow IV push or sometimes intramuscularly – but with some discomfort. DMPS reaches the saliva, hence is not appropriate for those that still have palladium or mercury dental restorations, unless used only as a challenge substance for testing. DMPS may be dosed orally as well.
Instruct patient to drink adequate amounts of pure water (an adult’s urine volume should be about 2 liters per day).
Click play to see a demonstration of the IAOMT's SMART protocol
for mercury amalgam removal.
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