Tetramethyl lead

  • Lead tetramethyl
  • Tetramethyl plumbane
Formula C4H12Pb
Structure
Description Colorless liquid, dyed red, orange or blue. Has a slight musty odor.
Uses Antiknock additive for gasolines.

Registry Numbers and Inventories.
CAS 75-74-1
EC (EINECS/ELINCS) 200-897-0
EC Risk Phrase R 26/27/28 33 61
EC Safety Phrase S 45 53
RTECS TP4725000
RTECS class Organometallic; Reproductive Effector
UN (DOT) 1649
Beilstein/Gmelin 3902986
Beilstein Reference 4-04-00-04348
RCRA D008
Swiss Giftliste 1 G-1276
Canada DSL/NDSL DSL
US TSCA Listed
Austrailia AICS Listed
Korea ECL Listed

Properties.
Formula C4H12Pb
Formula mass 267.35
Melting point, °C -27.5
Boiling point, °C 375
Vapor pressure, mmHg 18 (25 C)
Vapor density (air=1) 6.5
Density 2.034 g/cm3 (0 C)
Solubility in water 0.02 g/L
Viscosity 0.57 cp (20 C)
Refractive index 1.5068 (20 C)
Partition coefficient, pKow 2.98
Heat of fusion 10.8 kJ/mol
Heat of vaporization 34.5 kJ/mol
Heat of combustion -3285 kJ/mol

Hazards and Protection.
Storage Protect against physical damage. Outside or detached storage is preferred. Inside storage should be in a standard flammable liquids storage room or cabinet. Separate from halogens and other oxidizing agents. Protect against electrical sparks, open flames, or other heat sources. Tank storage should be protected by dikes, diversion walls or ditches and be sprinkled.
WHMIS B3
Handling All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Protection Wear appropriate personal protective clothing to prevent skin contact. Wear appropriate eye protection to prevent eye contact. Facilities for quickly drenching the body should be provided within the immediate work area for emergency use where there is a possibility of exposure.
Respirators Any self contained breathing apparatus with a full facepiece and operated in a pressure demand or other positive pressure mode or any supplied air respirator with a full facepiece and operated in a pressure demand or other positive pressure mode in combination with an auxiliary self contained breathing apparatus operated in pressure demand or other positive pressure mode.
Small spills/leaks Caution : Flammable liquid. Avoid sources of extreme heat or ignition including sparks or fire. When burned, toxic fumes of lead oxide will be emitted. Do not touch spilled material; stop leak if you can do it without risk. Use water spray to reduce vapors. Small spills: take up with sand or other non-combustible absorbent material and place into containers for later disposal. Large spills: dike far ahead of spill for later disposal.
Stability Reactive under confinement, extreme caution.
Incompatibilities Sensitive to heat Can react with strong oxidizers.
Decomposition Temperatures above 100 C (212 F) cause decomposition and development of pressure that may cause containers to burst. When heated to decomposition it emits toxic fumes of lead.

Fire.
Flash Point,°C 27
Lower exp. limit, % 1.8
Fire fighting Use water to keep fire exposed containers cool. If leak or spill has not ignited, use water spray to disperse vapors or flush spill. For massive fire in cargo area, use unmanned hose holder or monitor nozzle; if this is impossible withdraw from area and let fire burn.On fires in which containers are not exposed, use water spray, dry chemical, foam or carbon dioxide.
Fire potential Flammable liquid and vapor.
Hazards Thermal decomposition is likely to take the form of vapors at the surface. Rapid decomposition will cause container to explode. Dangerous fire hazard when exposed to heat, flame, or oxidizers. Toxic gases are generated in fire. Avoid strong oxidizers such as sulfuryl chloride or potassium permanganate. Avoid fire, heat, physical damage, and strong oxidizers. Starts to decompose at about 212F. If confined, may explode or detonate at high temperatures.
Combustion products Lead fumes and carbon monoxide
NFPA Health 2
  Flammability 3  
  Reactivity 3  
  Special W

Health.
Exposure limit(s) NIOSH REL: TWA 0.075 mg/m3 [skin] OSHA PEL: TWA 0.075 mg/m3 [skin] 40 mg/m3 (as Pb)
Carcinogin G-A3, I-2B, CP65
Poison_Class 1
Exposure effects Irregular breathing, abnormally low blood pressure, fever, or reduced body temperature have been reported. Clinical neurologic effects of organolead intoxication can be divided into mild, moderate, and severe. 1. Mild - anxiety, irritability, insomnia, lurid dreams, vomiting, metallic taste, pallor, cerebellar ataxia, and diarrhea. 2. Moderate - disorientation, hyperexcitability, tremors, chorea, bradycardia, hypotension, and hypothermia. 3. Severe - delusions, hallucinations, mania, convulsions, cerebral edema, coma, and death. Tetramethyl lead is fetotoxic, but not teratogenic, in rats. <br>&nbsp;&nbsp;&nbsp;1. The offspring of heavy gasoline sniffers have had severe mental retardation. <br>&nbsp;&nbsp;&nbsp;2. Organolead has reduced libido, potency, and spermatogenesis in occupationally exposed men.
   Ingestion Abdominal pain. Burning sensation. Diarrhoea. Dullness.
   Inhalation Convulsions. Dizziness. Headache. Nausea. Unconsciousness. Hallucination. Symptoms may be delayed.
   Skin Irritation and pain. May be absorbed through the skin.
   Eyes Redness, pain.

First aid
 
   Ingestion The possible benefit of early removal of some ingested material by cautious gastric lavage must be weighed against potential complications of bleeding or perforation. Activated charcoal activated charcoal binds most toxic agents and can decrease their systemic absorption if administered soon after ingestion. Activated charcoal: administer charcoal as a slurry (240 ml water/30 g charcoal). Usual dose: 25 to 100 g in adults/adolescents.
   Inhalation Move patient to fresh air. Monitor for respiratory distress. If cough or difficulty breathing develops, evaluate for respiratory tract irritation, bronchitis, or pneumonitis. Administer oxygen and assist ventilation as required. Treat bronchospasm with beta2 agonist and corticosteroid aerosols.
   Skin Remove contaminated clothing and wash exposed area thoroughly with soap and water. A physician should examine the area if irritation or pain persists.
   Eyes Irrigate exposed eyes with copious amounts of tepid water for at least 15 minutes. If irritation, pain, swelling, lacrimation, or photophobia persist, the patient should be seen in a health care facility.

Transport.
UN number 1649
Response guide 131
Hazard class 6.1
Packing Group I  
USCG CHRIS Code TML  
IMO Chemical Code 17