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Tetra-ethyl lead
IUPAC nametetraethyllead, tetraethylplumbane
Other namesTEL; lead tetraethyl; tetra-ethyl lead
Identifiers
CAS number[78-00-2]
RTECS numberTP4550000
SMILESCC[Pb](CC)(CC)CC
Properties
Molecular formulaC8H20Pb
Molar mass323. IUPAC Nomenclature is a system of naming Chemical compounds and of describing the science of Chemistry in general CAS registry numbers are unique numerical identifiers for Chemical compounds Polymers biological sequences mixtures and Alloys They are also referred to Registry of Toxic Effects of Chemical Substances ( RTECS) is a Database of Toxicity information compiled from the open scientific literature without reference A chemical formula is a way of expressing information about the Atoms that constitute a particular Chemical compound, and how the relationship between those atoms changes Molar mass, symbol M, is the Mass of one mole of a substance ( Chemical element or Chemical compound) 44 g/mol
Appearancecolorless, viscous liquid
Density1. The density of a material is defined as its Mass per unit Volume: \rho = \frac{m}{V} Different materials usually have different 653 g/mL at 25 °C
Melting point

−136 °C

Boiling point

84–85 °C@15 mm Hg

Solubility in waterinsoluble
Refractive index (nD)1. The melting point of a solid is the temperature range at which it changes state from solid to Liquid. The boiling point of a liquid is the temperature at which the Vapor pressure of the liquid equals the environmental pressure surrounding the liquid Solubility is the characteristic Physical property referring to the ability of a given substance the Solute, to dissolve in a Solvent. Water is a common Chemical substance that is essential for the survival of all known forms of Life. The refractive index (or index of Refraction) of a medium is a measure for how much the speed of light (or other waves such as sound waves is reduced inside the medium 519
Structure
Molecular shapetetrahedral
Dipole moment0 D
Hazards
Main hazardstoxic, flammable
NFPA 704
2
3
3
 
R-phrasesR61, R26/27/28, R33, R50/53, R62
S-phrasesS53, S45, S60, S61
Flash point346 K - 73 °C - 163 °F
Related compounds
Other anionsTetraphenyllead
Other cationsTetramethylsilane; tetramethyltin
Related compoundsLead(II) chloride; decaphenylplumbocene
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)
Infobox disclaimer and references

Tetra-ethyl lead, abbreviated TEL, is an organometallic compound with the formula (CH3CH2)4Pb. Molecular geometry or molecular structure is the three- Dimensional arrangement of the Atoms that constitute a Molecule. In physics there are two kinds of dipoles ( Hellènic: di(s- = two- and pòla = pivot hinge An electric dipole is a The debye (symbol D) is a non- SI, CGS unit of electrical dipole moment. Occupational safety and health is a cross-disciplinary area concerned with protecting the Safety, Health and welfare of people engaged in Symbolism The four divisions are typically color-coded with blue indicating level of Health Hazard, red indicating R-phrases (short for Risk Phrases) are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous R-phrases (short for Risk Phrases) are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous R-phrases (short for Risk Phrases) are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous R-phrases (short for Risk Phrases) are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous R-phrases (short for Risk Phrases) are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous R-phrases (short for Risk Phrases) are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. The flash point of a flammable liquid is the lowest Temperature at which it can form an ignitable mixture in air An ion is an Atom or Molecule which has lost or gained one or more Valence electrons giving it a positive or negative electrical charge An ion is an Atom or Molecule which has lost or gained one or more Valence electrons giving it a positive or negative electrical charge Tetramethylsilane (abbreviated as TMS) is the Chemical compound with the formula Si(CH34 or SiMe4 (Me = CH3 Tetramethyltin is an Organometallic compound with the formula (CH34Sn Lead(II chloride has the formula PbCl2. It is also known as In Chemistry, the standard state of a material is its state at 1 bar (100 Kilopascals exactly Organometallic chemistry is the study of Chemical compounds containing bonds between Carbon and a Metal. Characteristics Lead has a dull luster and is a dense, Ductile, very soft highly Once a common anti-knock additive in gasoline (petrol), TEL usage was largely discontinued because of the toxicity of lead and its deleterious effect on catalytic converters. Knocking (also called knock, detonation or spark knock, pinking in UK English or pinging in US English in spark-ignition Lead poisoning (also known as saturnism, plumbism, or painter's colic) is a medical condition caused by increased levels of the metal Lead in A catalytic converter (colloquially "cat" or "catcon" is a device used to reduce the toxicity of emissions from an Internal combustion engine. It is still used as an additive in aviation fuel for piston engine powered aircraft. Avgas is a high-octane Aviation fuel used for Aircraft and Racing cars Avgas is a Portmanteau for aviation gasoline The internal combustion engine is an engine in which the Combustion of Fuel and an Oxidizer (typically air occurs in a confined space called a

Contents

Synthesis and properties

TEL is produced by reacting ethyl chloride with a sodium-lead alloy. Chloroethane or monochloroethane, commonly known by its old name ethyl chloride, is a Chemical compound once widely used in producing Tetra-ethyl lead Sodium (ˈsoʊdiəm is an element which has the symbol Na( Latin natrium, from Arabic natrun) atomic number 11 atomic mass 22 Characteristics Lead has a dull luster and is a dense, Ductile, very soft highly An alloy is a Solid solution or Homogeneous mixture of two or more elements, at least one of which is a Metal, which itself has [1]

4 NaPb + 4 CH3CH2Cl → (CH3CH2)4Pb + 4 NaCl + 3 Pb

Despite decades of research, no reactions were found to improve upon this rather difficult process that involves metallic sodium — a process with lithium was developed, but never put into practice before TEL was largely banned. Lithium (ˈlɪθiəm is a Chemical element with the symbol Li and Atomic number 3 A related compound, tetramethyl lead, was commercially produced by a different electrolytic reaction. The product, TEL, is a viscous colorless liquid. Viscosity is a measure of the resistance of a Fluid which is being deformed by either Shear stress or Extensional stress. Liquid is one of the principal States of matter. A liquid is a Fluid that has the particles loose and can freely form a distinct surface at the boundaries of Because TEL is charge neutral and contains an exterior of alkyl groups, it is highly lipophilic and soluble in petrol (gasoline). Lipophilicity, fat-liking, refers to the ability of a Chemical compound to dissolve in fats oils lipids and non-polar solvents such as Hexane or

A noteworthy feature of TEL is the weakness of its four C-Pb bonds. At the temperatures found in internal combustion engines (CH3CH2)4Pb decomposes completely into lead and lead oxides and combustible, short-lived ethyl radicals. The internal combustion engine is an engine in which the Combustion of Fuel and an Oxidizer (typically air occurs in a confined space called a In Chemistry, radicals (often referred to as free radicals) are atoms molecules or ions with Unpaired electrons on an otherwise Open shell Lead and lead oxide scavenge radical intermediates in combustion reactions. In Chemistry, radicals (often referred to as free radicals) are atoms molecules or ions with Unpaired electrons on an otherwise Open shell Combustion or burning is a complex sequence of Exothermic chemical reactions between a Fuel and an Oxidant accompanied by the production of This prevents ignition of unburnt fuel during the engine's exhaust stroke. [1] Lead itself is the reactive anti-knock agent, and TEL serves as a gasoline-soluble lead carrier. [1] When (CH3CH2)4Pb burns, it produces not only carbon dioxide and water, but also lead:

(CH3CH2)4Pb + 13 O2 → 8 CO2 + 10 H2O + Pb

This lead can oxidize further to give species such as lead oxide:

2Pb + O2 → 2PbO

The Pb and PbO would quickly accumulate and destroy an engine. For this reason, the lead scavengers 1,2-dibromoethane and 1,2-dichloroethane are used in conjunction with TEL — these agents form volatile lead(II) bromide and lead(II) chloride, respectively, which are exhausted from the engine and into the air. Lead(II bromide is the stable salt of Lead and Hydrobromic acid. Lead(II chloride has the formula PbCl2. It is also known as

Formulation of ethyl fluid

TEL was supplied for mixing with raw gasoline in the form of ethyl fluid, which was TEL blended together with the lead scavengers 1,2-dibromoethane and 1,2-dichloroethane. Ethyl fluid also contained a reddish dye which would distinguish treated gasoline from untreated gasoline and discourage the diversion of gasoline for other purposes such as cleaning.

Ethyl fluid was added to gasoline at rate of 1:1260, usually at the refinery. Because of the widespread use, specialised and toxic nature of ethyl fluid, the Ethyl Corporation developed an expertise in the handling and formulation of toxic organometallics. Ethyl Corporation is a fuel additive company headquartered in Richmond Virginia. During the first days of TEL manufacture, when safety procedures were yet to be developed, some 17 workers for the Ethyl Corporation and Standard Oil died during the 1920s from the effects of exposure to lead.

The classical formula for ethyl fluid is:

Dibromoethane and dichloroethane act in a synergistic manner, where a particular mixing ratio provides the best lead scavenging ability. [1]

Uses of tetraethyl lead as an antiknock agent

Tetraethyl lead was once used extensively as an additive in gasoline (petrol) for its ability to increase the fuel's octane rating. Gasoline additives increase Gasoline 's Octane rating or act as Corrosion inhibitors or lubricators, thus allowing the use of higher Compression The octane rating is a measure of the resistance of Gasoline and other Fuels to Detonation ( Engine knocking) in spark-ignition A high enough octane rating is required to prevent its detonation during the compression stroke ("knocking") in the engine. Knocking (also called knock, detonation or spark knock, pinking in UK English or pinging in US English in spark-ignition [1] Anti-knock agents allow the use of higher compression ratios for greater efficiency[2] and peak power. The compression ratio is a single number that can be used to predict the performance of any engine particularly piston engines (but can be used on essentially any Internal-combustion Fuel efficiency, in its basic sense is the same as Thermal efficiency, meaning the efficiency of a process that converts chemical potential energy contained in a carrier In Physics, power (symbol P) is the rate at which work is performed or energy is transmitted or the amount of energy required or expended for The use of TEL in gasoline was started in the US while in Europe alcohol was initially used. In Chemistry, an alcohol is any Organic compound in which a Hydroxyl group ( - O[[hydrogen H]]) is bound to a Carbon The advantages of leaded gasoline from its higher energy content and storage quality eventually led to a universal switch to leaded fuel. One of the greatest advantages of TEL over other anti-knock agents or the use of high octane blend stocks is the very low concentrations needed. Typical formulations called for 1 part of ethyl fluid (prepared TEL) to 1260 parts untreated gasoline. Competing anti-knock agents must be used in higher amounts and/or have a much lower energy level than natural gasoline. The higher energy content of leaded gasoline results in greater fuel efficiency.

When used as an antiknock agent, alcohol will cause fuel to absorb moisture from the air. In Chemistry, an alcohol is any Organic compound in which a Hydroxyl group ( - O[[hydrogen H]]) is bound to a Carbon Over time fuel humidity can rise leading to rusting and corrosion in the fuel line. Whereas TEL is highly soluble in gasoline, ethanol is poorly soluble and that solubility decreases as fuel humidity increases. Over time droplets and pools of water can form in the fuel system creating a risk for fuel line icing. High fuel humidity can also raise issues of biological contamination, as certain bacteria can grow on the surface of the water/gasoline interface thus forming bacterial mats in the fuel system. The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have TEL's biocidal properties help prevent fuel contamination and degradation from bacterial growth.

In most Western countries this additive went out of use in the late 20th century, because of the concerns over pollution of air, the areas around roads and the accumulative neurotoxicity of lead. A nation is a Human Cultural and Social Community. In as much as most members never meet each other yet feel a common bond it may be considered The twentieth century of the Common Era began on Bioaccumulation occurs when an organism absorbs a toxic substance at a rate greater than that at ftudruinsubstance is lost Characteristics Lead has a dull luster and is a dense, Ductile, very soft highly Use of TEL as a fuel additive would result in the fouling of catalytic converters. A catalytic converter (colloquially "cat" or "catcon" is a device used to reduce the toxicity of emissions from an Internal combustion engine. The need for TEL was lessened by several advances in automotive engineering and petroleum chemistry. Lower oil prices promoted the development of low compression engines that were not as sensitive to gasoline quality. Other anti-knocking additives (MMT, MTBE, ETBE) and cheaper methods for making higher octane blending stocks (reformate, iso-octane) reduced the need for TEL. Methylcyclopentadienyl manganese tricarbonyl (MMT is an Organometallic compound with the formula (CH3C5H4Mn(CO3 Methyl tert -butyl ether, also known as methyl tertiary butyl ether and MTBE, is a Chemical compound with molecular formula C5H12O Ethyl tert-butyl ether ( ETBE) is commonly used as an Oxygenate Gasoline additive in the production of Gasoline from Crude oil Catalytic reforming is a chemical process used to convert Petroleum refinery Naphthas typically having low octane ratings, into high-octane liquid products 224-Trimethylpentane, also known as isooctane, is an Octane Isomer which defines the 100 point on the Octane rating scale

As of 2007, unleaded automotive gasoline is available throughout the world, and the only countries in which leaded gasoline is extensively used are Yemen, Afghanistan and North Korea. Yemen ( Arabic: اليَمَن al-Yaman officially the Republic of Yemen ( Arabic: الجمهورية اليمنية al-Jumhuuriyya Afghanistan /æfˈgænɪstæn/ officially the Islamic Republic of Afghanistan ( Pashto: د افغانستان اسلامي جمهوریت, North Korea is the commonly used short form name for the Democratic People's Republic of Korea (or DPRK) a State located in East Asia, Leaded gasoline is still available in parts of Northwest Africa, Europe, Commonwealth of Independent States (CIS), Iraq, Jordan and the Palestinian territories[3]. For a topic outline on this subject see List of basic Iraq topics. Jordan, officially the Hashemite Kingdom of Jordan (الأردنّ al-Urdunn) is an Arab country in Southwest Asia spanning the southern Name There are differences of opinion as to what the Palestinian territories should be called

TEL remains an ingredient of high-octane racing fuels, and of 100 octane aviation fuel, as a suitable replacement for it in the aviation industry has not yet been found. The octane rating is a measure of the resistance of Gasoline and other Fuels to Detonation ( Engine knocking) in spark-ignition Aviation fuel is a specialized type of Petroleum -based fuel used to power Aircraft. Aviation refers to activities involving man-made flying devices ( Aircraft) including the people organizations and regulatory bodies involved with them For other uses of this term see Industry (disambiguation An industry (from Latin industrius, "diligent industrious" The current formulation of 100LL (low lead) aviation gasoline contains much less lead than did historical aviation gasolines.

Many vehicles produced before TEL's phase-out required modification to run successfully on unleaded gasoline. These modifications fell into two categories: those required for physical compatibility with nonleaded fuel, and those performed to compensate for the relatively low octane of early unleaded fuels. Physical compatibility is addressed by the installation of hardened exhaust valves and seats. Compatibility with reduced octane was addressed by reducing compression, generally by installing thicker cylinder head gaskets and/or rebuilding the engine with compression-reducing pistons. However, the appearance on the market of high-octane unleaded gasolines has reduced or eliminated the need to alter engines' compression ratios.

Toxicity

The toxicity of concentrated TEL was recognized early, and the sales of TEL were initially suspended for one year to conduct a hazard assessment. [1] The cases of fatal lead poisoning and serious symptoms of lead toxicity were, however, assumed to be restricted to TEL manufacture and ethyl fluid handling. Lead poisoning (also known as saturnism, plumbism, or painter's colic) is a medical condition caused by increased levels of the metal Lead in The low concentrations present in gasoline and exhaust were not perceived as immediately dangerous. In the engine exhaust, compounds of lead are dispersed as fine particulates. Lead pollution is dispersed into the air and into the vicinity of roads. Lead is a toxic metal that accumulates and has subtle and insidious neurotoxic effects at even very low levels, such as low IQ and antisocial behavior. Toxic metals are Metals that form Poisonous soluble compounds and have no biological role i Neurotoxicity occurs when the exposure to natural or artificial toxic substances which are called Neurotoxins alters the normal activity of the Nervous system in It has particularly deleterious effects on children. These concerns led to the ban on TEL in automobile gasoline. In a 2000 study, the highest blood lead levels were about 27 μg/dL (county averages). [4] A blood lead level of 30 μg/dL is associated with a 6. 9-point reduction of IQ, with most reduction (3. 9 points) occurring below 10 μg/dL, the level at which CDC considers blood lead level "elevated". [5] In the U. S. , a statistically significant correlation has been found between the use of TEL and violent crime: taking into account a 22-year time lag, the violent crime curve virtually tracks the lead exposure curve. [6] After the ban on TEL, blood lead levels in children have been dramatically reduced. [6]

Even though leaded gasoline is largely gone in North America, it has left high concentrations of lead in the dirt adjacent to all roads that were constructed prior to its phaseout. Child development specialists often advise parents to not let their children play in such dirt, especially because some children like to eat dirt (see pica). Pica is a medical disorder characterized by an Appetite for largely non-nutritive substances (e

History

TEL was found to be an effective anti-knocking agent by Thomas Midgley in 1921, working under Charles Kettering at General Motors Research. Thomas Midgley Jr ( May 18, 1889 – November 2, 1944) was an American mechanical engineer turned Chemist Year 1921 ( MCMXXI) was a Common year starting on Saturday (link will display full 1921 calendar of the Gregorian calendar Charles Franklin Kettering ( August 29, 1876 – November 24 or November 25, 1958) was an American inventor and the holder of General Motors Corporation ( GM) ( is a multinational automobile manufacturer founded in 1908 and headquartered in the United States. [7] Due to its extreme toxicity, many early TEL researchers, including Midgley, became lead poisoned, and dozens died. Toxicity is the degree to which a substance is able to damage an exposed organism Lead poisoning (also known as saturnism, plumbism, or painter's colic) is a medical condition caused by increased levels of the metal Lead in [8]. In 1924, Standard Oil of New Jersey (ESSO/EXXON) and General Motors created the Ethyl Gasoline Corporation to produce and market TEL. Year 1924 ( MCMXXIV) was a Leap year starting on Tuesday (link will display the full calendar of the Gregorian calendar. General Motors Corporation ( GM) ( is a multinational automobile manufacturer founded in 1908 and headquartered in the United States. Ethyl Corporation is a fuel additive company headquartered in Richmond Virginia. In the US in 1972, the EPA launched an initiative to phase out leaded gasoline, in response to which Ethyl Corp. The United States of America —commonly referred to as the Year 1972 ( MCMLXXII) was a Leap year starting on Saturday (link will display full calendar of the Gregorian calendar. to sue the EPA. The EPA won, so the phaseout began in 1976 and was completed by 1986. Year 1976 ( MCMLXXVI) was a Leap year starting on Thursday (link will display full calendar of the Gregorian calendar. Year 1986 ( MCMLXXXVI) was a Common year starting on Wednesday (link displays 1986 Gregorian calendar) A 1994 study indicated that the concentration of lead in blood dropped 78% from 1978 to 1991. Year 1994 ( MCMXCIV) was a Common year starting on Saturday (link will display full 1994 Gregorian calendar) Blood is a specialized Bodily fluid that delivers necessary substances to the body's cells such as nutrients and oxygen—and transports Waste products Year 1978 ( MCMLXXVIII) was a Common year starting on Sunday (link displays the 1978 Gregorian calendar) Year 1991 ( MCMXCI) was a Common year starting on Tuesday (link will display full calendar of the Gregorian Calendar.

As early as the late 1940s and early 1950s, Clair Cameron Patterson accidentally discovered the pollution caused by TEL in the environment while determining the age of the earth. Clair Cameron Patterson ( June 2, 1922 – December 5, 1995) was a Geochemist born in Mitchellville Iowa, United As he attempted to measure lead content of very old rocks, and the time it took uranium to decay into lead, the readings were made inaccurate by lead in the environment that contaminated his samples. He was then forced to work in a clean room to keep his samples uncontaminated by environmental pollution of lead. After coming up with a fairly accurate estimate of the age of the earth, he turned to investigating the lead contamination problem by examining ice cores from countries such as Greenland. He realized that the lead contamination in the environment dated from about the time that tetra-ethyl lead became widely used as a fuel additive in gasoline. Being aware of the health dangers posed by lead and suspicious of the pollution caused by tetra-ethyl lead, he was one of the earliest opponents of its use. Since the lead industry was powerful and used its influence to protect its practices, Patterson often found research funding withdrawn, and the trustees of his university were pressured to fire him or keep him quiet. He was even excluded from the 1971 US National Research Council panel that was investigating lead poisoning, despite the fact that he was the leading expert on atmospheric lead. [9]

Leaded gasoline was withdrawn entirely from the European Union market on the 1 January 2000, although it had been banned much earlier in some member states. It was only recently phased out in China (around 2001). China ( Wade-Giles ( Mandarin) Chung¹kuo² is a cultural region, an ancient Civilization, and depending on perspective a National In the United Kingdom a small amount of leaded gasoline ("four star petrol") is still permitted to be manufactured and sold[10], albeit with a higher rate of fuel duty. The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom, the UK or Britain,is a Sovereign state located

Alternative antiknock agents

Antiknock agents are grouped into "high percentage" additives, such as alcohol, and "low percentage" additives based on heavy elements. An antiknock agent is a Gasoline additive used to reduce Engine knocking and increase the fuel's Octane rating. Since the main problem with TEL is its lead content, many alternative additives that contain less poisonous metals have been examined. A manganese-carrying additive, methylcyclopentadienyl manganese tricarbonyl (MMT or methylcymantrene), is used as an antiknock agent in Canada, but its use as a fuel additive had been banned in the US until 1995. Methylcyclopentadienyl manganese tricarbonyl (MMT is an Organometallic compound with the formula (CH3C5H4Mn(CO3 Ferrocene, an organometallic compound of iron, has also been reported as an effective antiknock agent. Ferrocene is the Organometallic compound with the formula Fe(C5H52 Iron (ˈаɪɚn is a Chemical element with the symbol Fe (ferrum and Atomic number 26

High-percentage additives are organic compounds that do not contain metals, but they require much higher blending ratios, such as 20-30% for benzene and ethanol. It had also been established by 1921 that ethanol was an effective antiknock agent, but TEL was introduced for mainly commercial reasons to replace it. Oxygenates, mainly methanol-derived MTBE and ethanol-derived ETBE have largely substituted the need for TEL. Oxygenated chemical compounds contain Oxygen as a part of their chemical structure Methyl tert -butyl ether, also known as methyl tertiary butyl ether and MTBE, is a Chemical compound with molecular formula C5H12O Ethyl tert-butyl ether ( ETBE) is commonly used as an Oxygenate Gasoline additive in the production of Gasoline from Crude oil MTBE has environmental risks of its own and there are also bans on its use. Methyl tert -butyl ether, also known as methyl tertiary butyl ether and MTBE, is a Chemical compound with molecular formula C5H12O ETBE, on the other hand, requires more expensive ethanol as a starting material.

Improvements of the gasoline itself decrease the need for separate antiknock agents. Synthetic iso-octane and alkylate are examples of such blending stocks. 224-Trimethylpentane, also known as isooctane, is an Octane Isomer which defines the 100 point on the Octane rating scale Alkylation is the transfer of an Alkyl group from one Molecule to another Benzene and other high-octane aromatics can be also blended to raise the octane number, but they are disfavored today because of toxicity and carcinogenity.

References

  1. ^ a b c d e f Seyferth, D. , "The Rise and Fall of Tetraethyllead. 2", Organometallics, 2003, volume 22, pages 5154-5178.
  2. ^ Caris, D. F. and Nelson, E. E. 1959. A New Look at High Compression Engines SAE Trans.
  3. ^ Countries where Leaded Petrol is Possibly Still Sold for Road Use
  4. ^ US blood lead level study, 2000
  5. ^ Environ Health Perspect. 2005 July 113(7); 894-9.
  6. ^ a b The Impact of Childhood Lead Exposure on Crime
  7. ^ "Leaded Gasoline, Safe Refrigeration, and Thomas Midgley, Jr. " Chapter 6 in S. Bertsch McGrayne "Prometheans in the Lab" McGraw-Hill: New York, 2002. ISBN 0-07-140795-2
  8. ^ TEL-related deaths
  9. ^ "Getting the Lead Out" Chapter 10 in Bill Bryson "A Short History of Nearly Everything" Broadway Books: New York, 2003. ISBN 0-7679-0818-X
  10. ^ Leaded petrol remains on sale in the UK

See also

External links

Characteristics Lead has a dull luster and is a dense, Ductile, very soft highly Lead poisoning (also known as saturnism, plumbism, or painter's colic) is a medical condition caused by increased levels of the metal Lead in Elmer Keiser Bolton ( June 23, 1886 - July 30, 1968) was an American chemist and research director for DuPont, notable for his role Ethyl Corporation is a fuel additive company headquartered in Richmond Virginia. The UN Environment Programme (or UNEP) coordinates United Nations environmental activities assisting developing countries in implementing environmentally sound policies
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