Palladium

106.42

105.903481

231-115-6

5TWQ1V240M

DTXSID4064680

C95184

Silver-white, ductile metal|Steel white|Silver-white metal; cubic

28439000

0

0.00000

Silver-gray wire

12.02 g/cm³

1555 °C

3167 °C

H2O: INsoluble

Store at RT.

3.47 Pa (0.0260 mm Hg) at 1552 deg C

LD50 oral (rat) 200 mg/kg (palladium chloride) LC50 intratracheal (rat) 6 mg/kg (palladium chloride)

Explosive reaction with hydrogen and hydrogen peroxide.

Palladium is the lightest of the platinum group and very malleable and ductile when pure. It resists oxidation at ordinary temperatures. It absorbs a considerable amount of hydrogen gas. It is appreciably volatile at high temperatures. At red heat it is converted to the oxide.|Stable isotopes: (102)Pd, 1.02%; (1.4)Pd, 11.14%; (105)Pd, 22.23%; (106)Pd, 27.33%; (108)Pd, 26.46%; (110)Pd, 11.72%|Usual valency, 2,4; ionic radius, 65 pm, crystal structure, face-centered cubic; lattice constant, 389 pm; reflectance, 54%; thermal expansion, 11.11X10+6 °C-1; magnetic susceptibility, 5.23X10-6 cu cm/g; work function, 4.99 eV; Young's modulus, 1.24X10+8 kN/sq m; ultimate tensile strength, 180-200 MPa; Poisson's ratio, 0.39; Vicker's hardness, 40; temperature coefficient of resistance 3.8X10-3 K-1; electrical resistivity at 0 °C, 9.93 microohm-cm; thermal conductivity, 75 W/m K|Palladium is stable in air, even at elevated temperatures; shows no corrosion or tarnishing in hydrogen sulfide atmospheres.|For more Other Experimental Properties (Complete) data for PALLADIUM, ELEMENTAL (6 total), please visit the HSDB record page.

III

4.1

UN 3089 4.1/PG 2

-

61-33-37/38-40-41-36/37/38-11

53-26-36/37/39-24/25-36-22

RT3480500

T,F,Xi

Stable. Flammable - fine powder may cause fire or explosion in air. Incompatible with ozone, sodium tetrahydroborate, sulphur, arsenic.

P210-P261-P305 + P351 + P338

H228-H315-H319-H335

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational exposure or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in soil or water; effects on animal, aquatic, and plant life; and conformance with environmental and public health regulations.

Incompatibilities: Arsenic; carbon; ozonides; methanol; sulfur.|Reaction with formic acid or tetrahydroborate releases explosive hydrogen gas.|Violent reaction with isopropyl alcohol or OF2S.|At a red heat is converted in to the monoxide. Forms dihalides with fluorine or chlorine at a red heat. Reacts with nitric acid, sulfuric acid, a mixture of hydrochloric and choric acids. Reacts slightly with concentrated /hydrochloric acid/; more readily in the presence of air or free chlorine. Forms a sulfide when heated with sulfur, a phosphide when heated with phosphorus. Absorbs a considerable amount of hydrogen.

Noble metal alloy: (a) Identification. A noble metal alloy is a device composed primarily of noble metals, such as gold, palladium, platinum, or silver, that is intended for use in the fabrication of cast or porcelain-fused-to-metal crown and bridge restorations. (b) Classification. Class II (special controls). The special control for these devices is FDA's "Class II Special Controls Guidance Document: Dental Noble Metal Alloys." The devices are exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in §872.9. See §872.1(e) for availability of guidance information. /Noble metal alloy/

|Warning|H228 (51.36%): Flammable solid [Danger Flammable solids]|P210, P240, P241, P261, P264, P271, P273, P280, P302+P352, P304+P340, P305+P351+P338, P312, P321, P332+P313, P337+P313, P362, P370+P378, P403+P233, P405, and P501|Aggregated GHS information provided by 544 companies from 26 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Combustible in the form of dust when exposed to heat or flame.|Finely divided palladium (palladium black) used as a hydrogenation catalyst is usually pyrophoric and needs appropriate handling precautions.

Explosive reaction with hydrogen and hydrogen peroxide.

Contact dermatitis has been associated with metallic palladium, especially with palladium alloys ... .

Dust samples were collected in 1985 from the surfaces of plants along side roads in San Diego, CA; palladium concentrations ranged from 0.015 mg/kg dry weight in dust collected along Bellaire Court, a residential street with light traffic, up to 0.28 mg/kg dry weight in dust collected approximately 2 ft from the edge of Interstate 5, a major freeway(1). Palladium concentrations of 0.001-0.146 mg/kg were reported in urban road dusts in Germany in 1995(2).

IDENTIFICATION: Palladium is a steel white ductile metallic element. It is stable in air and resistant to attack by most reagents. It is soluble in a mixture of hydrochloric and nitric acids. Palladium and its alloys are used as catalysts in the petrochemical and automotive industries. Used in electronics and in dental applications. Purified metals between 99.9% and 99.99% are available for chemical use as foil, granules, rod or wire. HUMAN EXPOSURE: The general population is primarily exposed to palladium through dental alloys, jewlery, food and emissions from automobile catalytic converters. There are limited data concerning the distribution of palladium from dental resorations in human tissues or fluids. Populations at special risk of palladium allergy include people with known nickel allergy. ANIMAL STUDIES: Six months after a single intratracheal application of palladium dust, several histopathological signs of inflammation were noted in the lungs of rats. Daily oral administration of palladium dust over 6 months resulted in changes in several blood and urine parameters. Palladium applied in its metallic form showed no or little cytotoxicity.[

People with known metal (especially nickel) allergy may have an increased risk of palladium allergy.

Palladium (Pd) is found with platinum, gold, and nickel ores.|Palladium belongs to the platinum group metals (ruthenium, osmium, rhodium, iridium, palladium and platinum), which are rare elements often found together in nature(1). In the lithosphere, the estimated concentration of platinum group metals range from 0.05 to 0.5 ppm(2). Palladium's abundance in the earth's crust is 0.001-0.01 ppm(3).

Palladium concentrations in personal samples collected in 1996 during industrial operations involving the handling of palladium compounds were reported to be between 0.4 and 11.6 ug Pd/cu m as a 8-hour time-weighted average(1). Mean palladium concentrations of 3.5 ug/cu m, with local exhaust ventilation, and 5.5 ug/cu m, without dust control, were measured in the breathing zone of dental technicians(1). Palladium concentrations in air in a platinum and palladium refinery in New Jersey ranged from 0.001 to 0.36 ug/cu m(1).

103Pd has been used for cancer (e.g., prostrate) brachytherapy, a form of cancer radiation therapy in which radioactive sources are implanted directly into a malignant tumor.|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.

Six months after a single intratracheal application of 50 mg palladium dust (mass median aerodynamic diameter [MMAD] 3.92 um) to Sprague-Dawley rats, palladium particles were found to be localized intracellularly in alveolar macrophages.|The absorption of palladium from the GI tract is insignificant. A single intragastrical dose of 103Pd isotope given to male Charles River CD-1 rats was rapidly excreted from their organism with feces. ...After a single acute exposure, most of the absorbed dose is excreted within 48 hr to 5 days, although in the organs where Pd is accumulated, it may remain for 30 days after termination of the exposure.|...Colloidal palladium of known particle size (maximum diameter mostly 10-20 nm) was able to pass into the blood from the cerebrospinal subarachnoid space after its subarachnoid injection into cats.|No or little information is available on the mode of action of metallic palladium in its solid (alloys) or dispersed (dust particles) form in biological systems. It is assumed that, at least for processes in the oral cavity, ions can be formed from metallic palladium in dental restorations, leading to solution in the saliva and finally to distribution in the body. Fine particles of palladium may also be taken up by epithelial cells or lymphocytes and macrophages, etc., and be transported within the lymphatic system.

There are no established detoxification methods following poisoning by palladium or its compounds. Because of its poor absorption by the body, removal from exposure is the best remedy, when palladium is cleared by natural processes.|Basic treatment: Establish a patent airway. Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if needed. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Monitor for shock and treat if necessary ... . Anticipate seizures and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with normal saline during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 ml/kg up to 200 ml of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool ... . Cover skin burns with dry sterile dressings after decontamination ... . /Poison A and B/|Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in respiratory arrest. Positive pressure ventilation techniques with a bag valve mask device may be beneficial. Monitor cardiac rhythm and treat arrhythmias as necessary ... . Start an IV with D5W /SRP: "To keep open", minimal flow rate/. Use lactated Ringer's if signs of hypovolemia are present. Watch for signs of fluid overload. Consider drug therapy for pulmonary edema ... . For hypotension with signs of hypovolemia, administer fluid cautiously. Watch for signs of fluid overload ... . Treat seizures with diazepam (Valium) ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Poison A and B/

/CASE REPORTS/ A 54-yr-old woman patient had symptoms of stomatitis and asthma following the provision of a dental prosthesis in July 1991. ...A positive patch test reaction /was found/ to palladium only, without any concomitant metallic contact dermatitis; in particular there was no sensitization to nickel. This is a very rare sensitization. After replacement of the dental alloy the clinical symptoms improved.|/CASE REPORTS/ Granulomatous tissue reactions due to jewelry made of gold, silver, nickel and palladium are rare but nevertheless have been known for a long time. A female patient developed nodular infiltrates after having been pierced with ear stickers containing palladium. A contact allergic reaction could be demonstrated as the underlying cause by inducing similar histological changes following patch testing with palladium.|/CASE REPORTS/ A patient with a metal dental bridge complained of itching and pain in the oral cavity. She suffered also from recurrent blisters, ulceration, and infection of the oral mucous membrane. Skin tests carried out ... on this patient showed... a positive allergic reaction to... palladium metal.|/CASE REPORTS/ ...A case of linear lichen planus extending from the right cheek to the jaw, which was accompanied by itching and an unusual sensation in the mouth /is described/. The eruption was located along the mandible and aligned with the mandibular nerve. The right molars of the patient contained metal compounds and these were considered to be the cause of his disease. Patch testing with various dental metals showed positive reactions to palladium and platinum. A biopsy specimen showed a lichenoid reaction in the lesional tissue, and dermal contact dermatitis was noted at the palladium patch test site. His dentist reported that palladium-silver-gold or nickel-chrome alloys without platinum had been used in the crown and bridge of his molars. After removal of the dental alloys, the skin eruption resolved with some residual hyperpigmentation. In addition, the peculiar mouth sensation disappeared dramatically within 2 months.|For more Human Toxicity Excerpts (Complete) data for PALLADIUM, ELEMENTAL (11 total), please visit the HSDB record page.

Palladium

Grade: CP (99.99%), technical (99.0%)|Available as wire, leaf, powder, and single crystals.|Purified metals between 99.9% and 99.999% palladium are available for chemical or medical use as foil, granules, powder, rod or wire.

All other basic inorganic chemical manufacturing|Palladium: ACTIVE