Tetraethyllead

From Wikipedia, the free encyclopedia

Tetraethyllead
Skeletal formula
Ball-and-stick model
Names
Preferred IUPAC name
Tetraethylplumbane
Other names
Lead tetraethyl

Tetraethyl lead

Tetra-ethyl lead
Identifiers
3D model (JSmol)
Abbreviations TEL
3903146
ChEBI
ChemSpider
ECHA InfoCard 100.000.979 Edit this at Wikidata
EC Number
  • 201-075-4
68951
MeSH Tetraethyl+lead
RTECS number
  • TP4550000
UNII
UN number 1649
Properties
Chemical formula
 C8H20Pb
Molar mass 323.4 g·mol−1
Appearance Colorless liquid
Odor pleasant, sweet[1]
Density 1.653 g cm−3
Melting point −136 °C (−213 °F; 137 K)
Boiling point 84 to 85 °C (183 to 185 °F; 357 to 358 K) 15 mmHg
0.00002% (20 °C)[1]
Vapor pressure 0.2 mmHg (20 °C)[1]
Refractive index (nD)
 1.5198
Structure
Tetrahedral
Dipole moment
 0 D
Hazards
GHS pictograms GHS06: Toxic GHS08: Health hazard GHS09: Environmental hazard
GHS hazard statements
 H300, H310, H330, H360, H373, H400, H410
P201, P202, P260, P262, P264, P270, P271, P273, P280, P281, P284, P301+310, P302+350, P304+340, P308+313, P310, P314, P320, P321, P322, P330, P361, P363, P391, P403+233
NFPA 704 (fire diamond)
4
2
3
Flash point 73 °C (163 °F; 346 K)
Explosive limits 1.8%–?[1]
Lethal dose or concentration (LD, LC):
LD50 (median dose)
 35 mg/kg (rat, oral)
17 mg/kg (rat, oral)
12.3 mg/kg (rat, oral)[2]
LDLo (lowest published)
 30 mg/kg (rabbit, oral)
24 mg/kg (rat, oral)[2]
LC50 (median concentration)
 850 mg/m3 (rat, 1 hr)[2]
LCLo (lowest published)
 650 mg/m3 (mouse, 7 hr)[2]
NIOSH (US health exposure limits):
PEL (Permissible)
 TWA 0.075 mg/m3 [skin][1]
REL (Recommended)
 TWA 0.075 mg/m3 [skin][1]
IDLH (Immediate danger)
 40 mg/m3 (as Pb)[1]
Related compounds
Related compounds
 Tetraethylmethane
Tetraethylgermanium

Tetraethyltin

Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY  (what is checkY☒N ?)
Infobox references

Tetraethyllead (commonly styled tetraethyl lead), abbreviated TEL, is an organolead compound with the formula (CH3CH2)4Pb. It is a petro-fuel additive, first being mixed with gasoline beginning in the 1920s as a patented octane rating booster that allowed engine compression to be raised substantially. This in turn caused increased vehicle performance and fuel economy.[3][4] TEL had been identified chemically in the mid-19th century, but its antiknock effectiveness was discovered in 1921 by the General Motors research laboratory, which had spent several years attempting to find an additive that was both highly effective and inexpensive.

Concerns were later raised over the toxic effects of lead, especially on children. Lead also poisons catalytic converters and is a major cause of spark plug fouling.[5] From the 1970s many countries began phasing out and eventually banning TEL in automotive fuel. In 2011, a study backed by the United Nations estimated that the removal of TEL had resulted in $2.4 trillion in annual benefits, and 1.2 million fewer premature deaths.[6]

TEL is still used as an additive in some grades of aviation gasoline. Innospec has claimed to be the last firm legally making TEL, and as of 2013 TEL was being produced illegally by several companies in China.[7] In August 2021, the sale of leaded gasoline was completely phased out worldwide, prompting the UNEP to declare that "The era of leaded petrol is over!" (although it is still available in aviation fuel for small planes).[8]

Synthesis and properties[]

TEL is produced by reacting chloroethane with a sodium–lead alloy.[9][10]

4 NaPb + 4 CH 3CH2Cl → (CH3CH2)4Pb + 4 NaCl + 3 Pb

The product is recovered by steam distillation, leaving a sludge of lead and sodium chloride.[11] TEL is a viscous colorless liquid with a sweet odor.[12] Because TEL is charge neutral and contains an exterior of alkyl groups, it is highly lipophilic and soluble in petrol (gasoline).

Despite decades of research, no reactions were found to improve upon this rather difficult process that involves metallic sodium and converts only 25% of the lead to TEL. A related compound, tetramethyllead, was commercially produced by a different electrolytic reaction.[9] A process with lithium was developed but never put into practice.[13]

Reactions[]

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 as well as combustible, short-lived ethyl radicals. Lead and lead oxide scavenge radical intermediates in combustion reactions. Engine knock is caused by a cool flame, an oscillating low-temperature combustion reaction that occurs before the proper, hot ignition. Lead quenches the pyrolysed radicals and thus kills the radical chain reaction that would sustain a cool flame, preventing it from disturbing the smooth ignition of the hot flame front. Lead itself is the reactive antiknock agent, and TEL serves as a gasoline-soluble lead carrier.[9] When (CH3CH2)4Pb burns, it produces not only carbon dioxide and water, but also lead:[14]

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

This lead can oxidize further to give species such as lead(II) oxide:[14]

2 Pb + O2 → 2 PbO

Pb and PbO would quickly over-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 flushed from the engine and into the air.[14]

In motor fuel[]

TEL was extensively used as a gasoline additive beginning in the 1920s,[15] wherein it served as an effective antiknock agent and prevented exhaust valve and valve seat wear. Concerns were raised in reputable journals of likely health outcomes of fine particles of lead in the atmosphere.[16][17][18]

Valve wear preventative[]

Tetraethyllead works as a buffer against microwelds forming between the hot exhaust valves and their seats.[19] Once these valves reopen, the microwelds pull apart and leave the valves with a rough surface that would abrade the seats, leading to valve recession. When lead began to be phased out of motor fuel, the automotive industry began specifying hardened valve seats and upgraded exhaust valve materials to prevent valve recession without lead.[20]

Antiknock agent[]

A gasoline-fueled reciprocating engine requires fuel of sufficient octane rating to prevent uncontrolled combustion known as engine knocking (knock or ping).[9] Antiknock agents allow the use of higher compression ratios for greater efficiency[21] and peak power.[22] Adding varying amounts of additives such as low percentage TEL or high percentage ethanol to gasoline allowed easy inexpensive control of octane ratings. TEL offered the business advantage of being commercially profitable because its use for this purpose could be patented.[15] Aviation spirits with TEL used in WWII reached 150 octane to enable supercharged engines such as the Rolls-Royce Merlin and Griffon to reach high horsepower ratings at altitude.[23] In military aviation, TEL manipulation allowed a range of different fuels to be tailored for particular flight conditions.

In 1935 the licence to produce TEL was given to IG Farben, enabling the newly formed German Luftwaffe to use high-octane gasoline. A company, Ethyl GmbH, was formed that produced TEL at two sites in Germany with a government contract from 10 June 1936.[24]

Phaseout and ban[]

In most industrialized countries, a phaseout of TEL from road vehicle fuels was completed by the early 2000s because of concerns over air and soil lead levels and the accumulative neurotoxicity of lead. The use of catalytic converters, mandated in the US for 1975 and newer model-year cars to meet tighter emissions regulations, started a gradual phase-out of leaded gasoline in the US.[25] The need for TEL was lessened by several advances in automotive engineering and petroleum chemistry. Safer methods for making higher-octane blending stocks such as reformate and iso-octane reduced the need to rely on TEL, as did other antiknock additives of varying toxicity including metallic compounds such as methylcyclopentadienyl manganese tricarbonyl (MMT) as well as oxygenates including methyl tert-butyl ether (MTBE), tert-amyl methyl ether (TAME), and ethyl tert-butyl ether (ETBE).

Lead-replacement additives were scientifically tested, and some were approved by the Federation of British Historic Vehicle Clubs at the UK's Motor Industry Research Association in 1999.

In Europe, Professor Derek Bryce-Smith was among the first to highlight the potential dangers of TEL and became a leading campaigner for removal of lead additives from petrol.[26] However, leaded motor fuel re-entered the UK market in small quantities from 2000 in response to lobbying from classic-car organisations who contended their vehicles would be rendered useless without leaded fuel. Bayford & Co was the only wholesale supplier.[27]

Vehicles designed and built to run on leaded fuel may require modification to run on unleaded gasoline or autogas. These modifications fall into two categories: those required for physical compatibility with unleaded fuel, and those performed to compensate for the relatively low octane of early unleaded fuels. Physical compatibility requires 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. The availability of high-octane unleaded gasoline (or LPG) has reduced or eliminated the need to decrease compression ratios.

Leaded gasoline remained legal as of late 2014[28] in parts of Algeria, Iraq, Yemen, Myanmar, North Korea, and Afghanistan. It was available at the pump in most of these countries as of 2011, but very little was used in North Korea, and it was not clear whether it was sold in Afghanistan.[29][30][needs update] Specialty chemical company Innospec says that it is the world's only manufacturer of TEL[31] and sells it for automotive use nowhere except to Algeria as of late 2014.[28][needs update] Innospec previously sold TEL to Iraq and Yemen as of 2011, but remains unclear after head executives were charged for bribing various government state-owned oil companies, to approve the sale of their TEL products.[30][32] North Korea and Myanmar buy their TEL from China.[7] The governments of Algeria and Iraq have scheduled the final elimination of leaded gasoline in their countries in 2015, after refinery upgrades. The status in Afghanistan, Yemen, and Myanmar is unclear.[needs update]

As of June 2016 UNEP-sponsored phase-out was nearly complete: only Algeria, Iraq, and Yemen continued widespread use of leaded gasoline, although not exclusively.[33] In July 2021, the last country to sell it, Algeria, had halted the sale of leaded gasoline.[8]

In the European Union, tetraethyllead has been classified as a Substance of Very High Concern and placed on the Candidate List for Authorisation under Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH).[34] Potential use of TEL would need to be authorised through the REACH authorisation procedure. While not a complete ban, it introduces significant obligations such as a mandatory analysis of alternatives and socioeconomic analysis.

Leaded-fuel bans[]

Leaded-fuel bans for road vehicles came into effect as follows:

Africa[]
  • South Africa: 2006
  • Leaded petrol was supposed to be completely phased out continent-wide on 1 January 2006, following a ban initiated from the 2002 Earth Summit.[60] However, in Algeria refineries needed to be altered; as a result. As of 2021, the Algerian Government has banned the marketing of leaded petrol at all petrol stations in the country, it has now been effectively phased out.[61][62]

In motor racing[]

Leaded fuel was commonly used in professional motor racing, until its phase out beginning in the 1990s. Since 1993, Formula One racing cars have been required to use fuel containing no more than 5 mg/L of lead.[63]

NASCAR began experimentation in 1998 with an unleaded fuel, and in 2006 began switching the national series to unleaded fuel, completing the transition at the Fontana round in February 2007 when the premier class switched. This was influenced after blood tests of NASCAR teams revealed elevated blood lead levels.[64][65]

Aviation gasoline[]

Main article: Avgas

TEL remains an ingredient of 100 octane avgas for piston-engine aircraft. The current formulation of 100LL (low lead, blue) aviation gasoline contains 2.12 grams per US gallon (0.56 g/l) of TEL, half the amount of the previous 100/130 (green) octane avgas (at 4.24 grams per gallon),[66] and twice as much as the 1 gram per gallon permitted in regular automotive leaded gasoline prior to 1988 and substantially greater than the allowed 0.001 grams per gallon in automotive unleaded gasoline sold in the United States today.[67] The United States Environmental Protection Agency, FAA, and others are working on economically feasible replacements for leaded avgas, which still releases 100 tons of lead every year.[68] Children living near airports servicing small (piston-engine) aircraft have measurably higher concentrations of lead in their blood.[69]

Alternative antiknock agents[]

Antiknock agents are classed as high-percentage additives, such as alcohol, and low-percentage additives based on heavy elements. 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), was used for a time as an antiknock agent, though its safety is controversial and it has been the subject of bans and lawsuits. Ferrocene, an organometallic compound of iron, is also used as an antiknock agent although with some significant drawbacks.[70]

High-percentage additives are organic compounds that do not contain metals, but require much higher blending ratios, such as 20–30% for benzene and ethanol. It had been established by 1921 that ethanol was an effective antiknock agent, but TEL was introduced instead mainly for commercial reasons.[25] Oxygenates such as TAME derived from natural gas, MTBE made from methanol, and ethanol-derived ETBE, have largely supplanted TEL. MTBE has environmental risks of its own and there are also bans on its use.

Improvements to gasoline itself decrease the need for antiknock additives. Synthetic iso-octane and alkylate are examples of such blending stocks. Benzene and other high-octane aromatics can be also blended to raise the octane number, but they are disfavored today because of toxicity and carcinogenicity.

Formulation of ethyl fluid[]

Sign on an antique gasoline pump advertising tetraethyllead by the Ethyl Corporation

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

In the 1920s before safety procedures were yet developed, 17 workers for the Ethyl Corporation, DuPont, and Standard Oil died from the effects of exposure to lead.[15]

The formula for ethyl fluid is:[9]

  • Tetraethyllead 61.45%
  • 1,2-dibromoethane 17.85%
  • 1,2-dichloroethane 18.80%
  • Inerts and dye 1.90%

Dibromoethane and dichloroethane act in a synergistic manner, where a particular mixing ratio provides the best lead scavenging ability.[9]

Toxicity[]

Tetraethyllead is highly toxic, with as little as 6-15mL being enough to induce severe lead poisoning.[71] The hazards of TEL's lead content are heightened due to the compound's volatility and high lipophilicity, enabling it to easily cross the blood-brain barrier and accumulate in the limbic system, frontal cortex, and hippocampus, making chelation therapy ineffective.

Early symptoms of acute exposure to tetraethyllead can manifest as irritation of the eyes and skin, sneezing, fever, vomiting, and a metallic taste in the mouth. Later symptoms of acute TEL poisoning include pulmonary edema, anemia, ataxia, convulsions, severe weight loss, delirium, irritability, hallucinations, nightmares, fever, muscle and joint pain, swelling of the brain, coma, and damage to cardiovascular and renal organs.[72]

Chronic exposure to TEL can cause long-term negative effects such as memory loss, delayed reflexes, neurological problems, insomnia, tremors, psychosis, loss of attention, and an overall decrease in IQ and cognitive function.[73]

The carcinogenity of tetraethyllead is debatable. It is believed to harm the male reproductive system and cause birth defects.[74]

Concerns over the toxicity of lead[75] eventually led to the ban on TEL in automobile gasoline in many countries. Some neurologists have speculated that the lead phaseout may have caused average IQ levels to rise by several points in the US (by reducing cumulative brain damage throughout the population, especially in the young). For the entire US population, during and after the TEL phaseout, the mean blood lead level dropped from 16 μg/dL in 1976 to only 3 μg/dL in 1991.[76] The US Centers for Disease Control considered blood lead levels "elevated" when they were above 10 μg/dL.

History[]

In 1853, German chemist Karl Jacob Löwig (1803–1890) first prepared what he claimed was Pb2(C2H5)3 from ethyl iodide and an alloy of lead and sodium.[77] In 1859, English chemist George Bowdler Buckton (1818–1905) reported what he claimed was Pb(C2H5)2 from zinc ethyl (Zn(C2H5)2) and lead(II) chloride.[78] Later authors credit both methods of preparation with producing tetraethyl lead.[79]

TEL in fuels[]

Regardless of the details of the chemical discoveries, tetraethyl lead remained unimportant commercially until the 1920s.[25] In 1921, at the direction of DuPont Corporation, which manufactured TEL, it was found to be an effective antiknock agent by Thomas Midgley, working under Charles Kettering at General Motors Corporation Research.[80] General Motors patented the use of TEL as an antiknock agent and used the name "Ethyl" that had been proposed by Kettering in its marketing materials, thereby avoiding the negative connotation of the word "lead".[25] Early research into "engine knocking" (also called "pinging" or "pinking") was also led by A.H. Gibson and Harry Ricardo in England and Thomas Boyd in the United States. The discovery that lead additives modified this behavior led to the widespread adoption of their use in the 1920s, and therefore more powerful, higher-compression engines.[15] In 1924, Standard Oil of New Jersey (ESSO/EXXON) and General Motors created the Ethyl Gasoline Corporation to produce and market TEL. Deepwater, New Jersey, across the river from Wilmington, was the site for production of some of DuPont's most important chemicals, particularly tetraethyl lead (TEL). After TEL production at the Bayway Refinery was shut down, Deepwater was the only plant in the Western hemisphere producing TEL up to 1948, when it accounted for the bulk of the Dupont/Deepwater's production.[81]

Controversy and phase-out[]

The toxicity of concentrated TEL was recognized early on, as lead had been recognized since the 19th century as a dangerous substance that could cause lead poisoning. In 1924, a public controversy arose over the "loony gas", after five[82] workers died, and many others were severely injured, in Standard Oil refineries in New Jersey.[83] There had also been a private controversy for two years prior to this controversy; several public health experts, including Alice Hamilton and Yandell Henderson, engaged Midgley and Kettering with letters warning of the dangers to public health.[15] After the death of the workers, dozens of newspapers reported on the issue.[84] The New York Times editorialized in 1924 that the deaths should not interfere with the production of more powerful fuel.[15]

To settle the issue, the U.S. Public Health Service conducted a conference in 1925, and the sales of TEL were voluntarily suspended for one year to conduct a hazard assessment.[9][25][85] The conference was initially expected to last for several days, but reportedly the conference decided that evaluating presentations on alternative anti-knock agents was not "its province", so it lasted a single day. Kettering and Midgley stated that no alternatives for anti-knocking were available, although private memos showed discussion of such agents. One commonly discussed agent was ethanol. The Public Health Service created a committee that reviewed a government-sponsored study of workers and an Ethyl lab test, and concluded that while leaded gasoline should not be banned, it should continue to be investigated.[15] The low concentrations present in gasoline and exhaust were not perceived as immediately dangerous. A U.S. Surgeon General committee issued a report in 1926 that concluded there was no real evidence that the sale of TEL was hazardous to human health but urged further study.[25] In the years that followed, research was heavily funded by the lead industry; in 1943, found children with lead poisoning had behavior problems, but the Lead Industries Association threatened him with a lawsuit and the research ended.[15][86]

In the late 1920s, Robert A. Kehoe of the University of Cincinnati was the Ethyl Corporation's chief medical consultant and one of the lead industry's staunchest advocates, who would not be discredited until decades later by Dr. Clair Patterson's work on human lead burdens (see below) and other studies.[25] In 1928, Dr. Kehoe expressed the opinion that there was no basis for concluding that leaded fuels posed any health threat.[25] He convinced the Surgeon General that the dose–response relationship of lead had "no effect" below a certain threshold.[87] As the head of Kettering Laboratories for many years, Kehoe would become a chief promoter of the safety of TEL, an influence that did not begin to wane until about the early 1960s. But by the 1970s, the general opinion of the safety of TEL would change, and by 1976 the U.S. government would begin to require the phaseout of this product.

In 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. 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 cleanroom 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 TEL 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 TEL, he became one of the earliest and most effective proponents of removing it from use.[88]

In the 1960s, the first clinical works were published proving the toxicity of this compound in humans, e.g. by Mirosław Jan Stasik.[72]

In the 1970s, Herbert Needleman found that higher lead levels in children were correlated with decreased school performance. Needleman was repeatedly accused of scientific misconduct by individuals within the lead industry, but he was eventually cleared by a scientific advisory council.[15] Needleman also wrote the average US child's blood lead level was 13.7 μg/dl in 1976 and that Patterson believed that everyone was to some degree poisoned by TEL in gasoline.[89]

In the U.S. in 1973, the United States Environmental Protection Agency issued regulations to reduce the lead content of leaded gasoline over a series of annual phases, which therefore came to be known as the "lead phasedown" program. EPA's rules were issued under section 211 of the Clean Air Act, as amended 1970. The Ethyl Corp challenged the EPA regulations in Federal court. Although the EPA's regulation was initially invalidated,[15] the EPA won the case on appeal, so the TEL phasedown began to be implemented in 1976. Additional regulatory changes were made by EPA over the next decade (including adoption of a trading market in "lead credits" in 1982 that became the precursor of the Acid Rain Allowance Market, adopted in 1990 for SO2), but the decisive rule was issued in 1985.[90] Then EPA mandated that lead additive be reduced by 91 percent by the end of 1986. A 1994 study had indicated that the concentration of lead in the blood of the U.S. population had dropped 78% from 1976 to 1991.[91] The U.S. phasedown regulations also were due in great part to studies conducted by Philip J. Landrigan.[92]

In 1995, leaded fuel accounted for only 0.6% of total gasoline sales and less than 2000 short tons (1814 t) of lead per year. From 1 January 1996, the U.S. Clean Air Act banned the sale of leaded fuel for use in on-road vehicles although that year the US EPA indicated that TEL could still be used in aircraft, racing cars, farm equipment, and marine engines.[93] Thus, what had begun in the U.S. as a phasedown ultimately ended in a phase-out for on-road vehicle TEL. Similar bans in other countries have resulted in lowering levels of lead in people's bloodstreams.[94][95]

Taking cue from the domestic programs, the U.S. Agency for International Development undertook an initiative to reduce tetraethyl lead use in other countries, notably its efforts in Egypt begun in 1995. In 1996, with the cooperation of the U.S. AID, Egypt took almost all of the lead out of its gasoline. The success in Egypt provided a model for AID efforts worldwide.[96]

By 2000, the TEL industry had moved the major portion of their sales to developing countries whose governments they lobbied against phasing out leaded gasoline.[25] Leaded gasoline was withdrawn entirely from the European Union market on 1 January 2000, although it had been banned much earlier in most member states. Other countries also phased out TEL.[97] India banned leaded petrol in March 2000.[56]

By 2011, the United Nations announced that it had been successful in phasing out leaded gasoline worldwide. "Ridding the world of leaded petrol, with the United Nations leading the effort in developing countries, has resulted in $2.4 trillion in annual benefits, 1.2 million fewer premature deaths, higher overall intelligence and 58 million fewer crimes," the United Nations Environmental Programme said.[6][98] The announcement was slightly premature, as a few countries still have leaded gasoline for sale as of 2017.[33] On 30 August 2021 the United Nations Environment Programme announced that leaded gasoline had been eliminated. The final stocks of the product were used up in Algeria, which had continued to produce leaded gasoline until July 2021.[99][100]

Effect on crime rates[]

Main article: Lead–crime hypothesis

Reduction in the average blood lead level is believed to have been a major cause for falling violent crime rates in the United States.[101] A statistically significant correlation has been found between the usage rate of leaded gasoline and violent crime: the violent crime curve virtually tracks the lead exposure curve with a 22-year time lag.[76][102] After the ban on TEL, blood lead levels in US children dramatically decreased.[76] Researchers including Amherst College economist Jessica Wolpaw Reyes, Department of Housing and Urban Development consultant Rick Nevin, and Howard Mielke of Tulane University say that declining exposure to lead is responsible for an up to 56% decline in crime from 1992 to 2002.[103] Taking into consideration other factors that are believed to have increased crime rates over that period, Reyes found that the reduced exposure to lead led to an actual decline of 34% over that period.[104][105]

Although leaded gasoline is largely gone in North America, it has left high concentrations of lead in the soil adjacent to roads that were heavily used prior to its phaseout. Children are particularly at risk if they consume this.[106]

See also[]

  • Elmer Keiser Bolton
  • Ethyl Corporation
  • Lead
    • Lead abatement
    • Lead and crime hypothesis
    • Organolead chemistry
    • Poisoning from lead
    • Tetramethyl lead
  • List of petrol additives
  • Thomas Midgley Jr. – discovered that the addition of tetraethyllead to gasoline prevented "knocking" in internal combustion engines

References[]

  1. ^ Jump up to: a b c d e f g NIOSH Pocket Guide to Chemical Hazards. "#0601". National Institute for Occupational Safety and Health (NIOSH).
  2. ^ Jump up to: a b c d "Tetraethyl lead". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
  3. ^ "Tetra-Ethyl Lead as an Addition to Petrol". British Medical Journal. 1 (3504): 366–7. 3 March 1928. doi:10.1136/bmj.1.3504.366. PMC 2455205. PMID 20773729.
  4. ^ "After Lead?", Popular Science (October 1987 ed.), Bonnier Corporation, p. 94, October 1987
  5. ^ Operator's Manual: Army Model U-8F Aircraft. Headquarters, Department of the Army (U.S.). 21 March 1978. p. 2−15.
  6. ^ Jump up to: a b "Phase-out of leaded petrol brings huge health and cost benefits". UN News. 27 October 2011. Retrieved 28 November 2020.
  7. ^ Jump up to: a b Chung, Kevin (16 August 2013). TEL for MOGAS manufacture in China (PDF) (Report). Summer Hill, NSW, Australia: The LEAD Group, Inc. Retrieved 14 January 2018.
  8. ^ Jump up to: a b "It's official: You can't buy leaded gasoline for cars anywhere on Earth". cbc.ca. CBC News. 30 August 2021. Retrieved 30 August 2021.
  9. ^ Jump up to: a b c d e f g Seyferth, D. (2003). "The Rise and Fall of Tetraethyllead. 2". Organometallics. 22 (25): 5154–5178. doi:10.1021/om030621b.
  10. ^ Jewkes, John; Sawers, David; Richard, Richard (1969). The sources of invention (2nd ed.). New York: W.W. Norton. pp. 235–237. ISBN 978-0-393-00502-8. Retrieved 11 July 2018.
  11. ^ Davis, William E. (1973). Emission Study of Industrial Sources of Lead Air Pollutants, 1970. Environmental Protection Agency. p. 57.
  12. ^ Dara, S.S.; Shete, S.D. S. Chand’s Applied Chemistry Volume - 2 (For 2nd Semester of Mumbai University). S. Chand Publishing. p. 93. ISBN 978-81-219-3495-4.
  13. ^ Seyferth, Dietmar (December 2003). "The Rise and Fall of Tetraethyllead. 2". Organometallics. 22 (25): 5174. doi:10.1021/om030621b. ISSN 0276-7333.
  14. ^ Jump up to: a b c Kloprogge, J. Theo; Ponce, Concepcion P.; Loomis, Tom (18 November 2020). The Periodic Table: Nature's Building Blocks: An Introduction to the Naturally Occurring Elements, Their Origins and Their Uses. Elsevier. p. 826. ISBN 978-0-12-821538-8.
  15. ^ Jump up to: a b c d e f g h i j Kovarik, W. (2005). "Ethyl-leaded gasoline: how a classic occupational disease became an international public health disaster" (PDF). Int J Occup Environ Health. 11 (4): 384–97. doi:10.1179/oeh.2005.11.4.384. PMID 16350473. S2CID 44633845. Archived from the original (PDF) on 11 July 2014.
  16. ^ Seyferth, Dietmar (June 2003). "The Rise and Fall of Tetraethyllead. 1. Discovery and Slow Development in European Universities, 1853−1920". Organometallics. 22 (12): 2346–2357. doi:10.1021/om030245v.
  17. ^ Seyferth, Dietmar (December 2003). "The Rise and Fall of Tetraethyllead. 2" (PDF). Organometallics. 22 (25): 5154–5178. doi:10.1021/om030621b. Retrieved 7 October 2018.
  18. ^ "A New Automobile Fuel". The Advertiser (Adelaide). South Australia. 16 January 1924. p. 15. Retrieved 25 April 2017 – via National Library of Australia.
  19. ^ "1972 Imperial & Chrysler Engine Performance Facts & Fixes Service Book (Session 291)". Online Imperial Club.
  20. ^ "1973 Imperial and Chrysler Clean Air System Reference Service Repair Book from the Master Technician's Service Conference (Session 302)". Online Imperial Club.
  21. ^ Caris, D. F.; Nelson, E. E. (1959). A New Look at High Compression Engines (Technical report). Society of Automotive Engineers. doi:10.4271/590015. 590015.
  22. ^ Loeb, A. P. (Fall 1995). "Birth of the Kettering Doctrine: Fordism, Sloanism and Tetraethyl Lead" (PDF). Business and Economic History. 24 (2). Archived (PDF) from the original on 27 October 2015.
  23. ^ F. R. Banks (1978). I Kept No Diary. Airlife Publishing, Ltd. ISBN 978-0-9504543-9-9.
  24. ^ Rainer Karlsch, Raymond G. Stokes. "Faktor Öl". Die Mineralölwirtschaft in Deutschland 1859–1974. C. H. Beck, München, 2003, ISBN 3-406-50276-8, p. 187.
  25. ^ Jump up to: a b c d e f g h i Kitman, J. (2 March 2000). "The Secret History of Lead." The Nation. Retrieved 17 August 2009.
  26. ^ Gilbert, Andrew (19 July 2011). "Derek Bryce-Smith obituary". the Guardian.
  27. ^ Uddin, Jamal (29 June 2012). Macro To Nano Spectroscopy. BoD – Books on Demand. p. 31. ISBN 978-953-51-0664-7.
  28. ^ Jump up to: a b "Corrupt Executives Sent To Prison For Pumping Toxic Leaded Fuel Overseas".
  29. ^ "UNEP 10th general meeting strategy presentation" (PDF). Archived from the original (PDF) on 3 December 2013.
  30. ^ Jump up to: a b Robert Taylor (17 June 2011). "Countries where Leaded Petrol is Possibly Still Sold for Road Use". The LEAD Group.
  31. ^ "Octane Additives". www.innospecinc.com.
  32. ^ "First Enforcement Action of 2011 Involves a Former Executive Officer". FCPA Professor. 25 January 2011.
  33. ^ Jump up to: a b "UNEP – Transport – Partnership for Clean Fuels and Vehicles" (PDF). Leaded Petrol Phase-out: Global Status as at March 2017. Archived from the original (PDF) on 15 November 2017. Retrieved 28 April 2018.
  34. ^ Inclusion of Substances of Very High Concern in the Candidate List – Decision of the European Chemicals Agency ED/169/2012. https://echa.europa.eu/documents/10162/0b417b76-b533-42a1-9bd2-519f1dc1990d
  35. ^ OECD Environmental Performance Reviews OECD Environmental Performance Reviews: Czech Republic 2005. OECD Publishing. 11 October 2005. ISBN 9789264011793 – via Google Books.
  36. ^ "Regulering af brændstoffer" (in Danish). Archived from the original on 11 August 2014. Retrieved 13 March 2016.
  37. ^ European Union Member States which had not already withdrawn it from sale experienced the EU-wide ban from 1 January 2000. Earlier regulation had prevented the sale or production of cars using leaded petrol after 1992
  38. ^ "Bensiiniopas" (PDF) (in Finnish). Archived (PDF) from the original on 9 October 2015. Retrieved 28 December 2017.
  39. ^ Oecd (26 September 2005). OECD Environmental Performance Reviews OECD Environmental Performance ... ISBN 9789264009141.
  40. ^ "Stirbt das Blei, dann lebt der Wald". Zeit (in German). 8 November 2013.
  41. ^ OECD Environmental Performance Reviews OECD Environmental Performance Reviews: Greece 2009. OECD Publishing. 15 March 2010. ISBN 9789264061330 – via Google Books.
  42. ^ OECD Environmental Performance Reviews OECD Environmental Performance Reviews: Italy 2002. OECD Publishing. 29 January 2003. ISBN 9789264199163 – via Google Books.
  43. ^ Oecd (2 June 2003). OECD Environmental Performance Reviews OECD Environmental Performance ... ISBN 9789264101005.
  44. ^ "Zakończenie produkcji Etyliny 94 - PKN ORLEN". www.orlen.pl.
  45. ^ OECD Environmental Performance Reviews OECD Environmental Performance Reviews: Slovenia 2012. OECD Publishing. 6 June 2012. ISBN 9789264169265 – via Google Books.
  46. ^ "Prohibición de la venta de gasolina con plomo" (in Spanish). Mº de Industria, Energía y Turismo. Retrieved 2 February 2018.
  47. ^ "Dispare benzina cu plumb". Evenimentul Zilei (in Romanian). 27 July 2004. Archived from the original on 29 July 2013.
  48. ^ "Постановление ГД ФС РФ от 15 November 2002 N 3302-III ГД О проекте Федерального закона N 209067-3 "Об ограничении оборота этилированного бензина в Российской Федерации"" [Resolution of the State Duma of the Federal Assembly of the Russian Federation of 15 November 2002 N 3302-III of the State Duma on the Draft Federal Law N 209067-3 "On Limiting the Turnover of Leaded Petrol in the Russian Federation"] (in Russian). Archived from the original on 29 July 2013. Retrieved 24 March 2013.
  49. ^ A. Muslibegović (8 June 2010). "Zbogom olovnom benzinu!" (in Serbian).
  50. ^ "Four-star petrol banned". BBC. 1 December 1998. Archived from the original on 10 August 2017. Retrieved 2 February 2018.
  51. ^ Wang ST, Pizzolato S, Demshar HP, Smith LF (1997). "Decline in blood lead in Ontario children correlated to decreasing consumption of leaded gasoline, 1983-1992". Clin Chem. 43 (7): 1251–2. doi:10.1093/clinchem/43.7.1251. PMID 9216473.CS1 maint: multiple names: authors list (link)
  52. ^ Jump up to: a b c Eichler, Anja; Gramlich, Gabriela; Kellerhals, Thomas; Tobler, Leonhard; Schwikowski, Margit (6 March 2015). "Pb pollution from leaded gasoline in South America in the context of a 2000-year metallurgical history". Scientific Advances. 1 (2): e1400196. Bibcode:2015SciA....1E0196E. doi:10.1126/sciadv.1400196. PMC 4643815. PMID 26601147.
  53. ^ "ENAP dejará de distribuir gasolina con plomo el sabado". 26 March 2001. Retrieved 1 August 2014. Cite journal requires |journal= (help)
  54. ^ Gabriel Reyes Aldana (10 July 1997). "La gasolina no tiene plomo". El Tiempo.
  55. ^ "Udelar y contaminación con plomo: trabajo continuo". 16 August 2019. Retrieved 21 May 2021. Cite journal requires |journal= (help)
  56. ^ Jump up to: a b Venkatesh, Thuppil (4 June 2015). "A Surprising Source of Lead Poisoning: India's Idols". WSJ. Retrieved 18 April 2016.
  57. ^ Kadir, M.M.; Janjua, N.Z.; Kristensen, S.; Fatmi, Z.; Sathiakumar, N. (2008). "Status of children's blood lead levels in Pakistan: implications for research and policy". Public Health. 122 (7): 708–15. doi:10.1016/j.puhe.2007.08.012. PMC 2494596. PMID 18359052.
  58. ^ "UAE switches to unleaded fuel". gulfnews.com. 1 January 2003. Retrieved 28 November 2020.
  59. ^ "Australia Cuts Sulfur Content in Transport Fuels". Environment News Service. 26 July 2004. Archived from the original on 22 April 2005.
  60. ^ Lean, Geoffrey (1 January 2006). "UN hails green triumph as leaded petrol is banned throughout Africa". The Independent. Archived from the original on 12 November 2010.
  61. ^ Chandola, Priyanka (6 January 2015). "Africa adopts continent-wide sustainable transport agenda". Archived from the original on 19 September 2015.
  62. ^ "Marketing of Super-Leaded Petrol to stop as of 2021". Algeria Press Service. Algeria Press Service. 28 September 2020. Retrieved 24 August 2021.
  63. ^ "FIA Formula 1 Technical Regulations 2018 (published 07/12/2017)".
  64. ^ O'Neil, J.; Steele, G.; McNair, C.S.; Matusiak, M.M.; Madlem, J. (2006). "Blood lead levels in NASCAR Nextel Cup Teams". Journal of Occupational and Environmental Hygiene. 3 (2): 67–71. doi:10.1080/15459620500471221. PMID 16361219. S2CID 33119520.
  65. ^ "NASCAR to Use Unleaded Fuel in 2008". Archived from the original on 28 May 2008. Retrieved 5 January 2020.
  66. ^ "Issues Related to Lead in Avgas". Aircraft Owners and Pilots Association. 8 March 2016. Archived from the original on 18 September 2011.
  67. ^ "Modifications / Octane / Lead Content / Fuel Specs / Limitations / Certification". Petersen Aviation Inc. Archived from the original on 30 March 2012.
  68. ^ Bryan, Chelsea (30 July 2014). "US leads Avgas effort for lead-free air". www.runwaygirlnetwork.com. Kirby Media Group. Retrieved 31 July 2014.
  69. ^ "Airports' leaden fallout may taint some kids". Science News. Retrieved 26 December 2018.
  70. ^ "Application of fuel additives" (PDF). Archived from the original (PDF) on 5 May 2006.
  71. ^ "TETRAETHYL LEAD - National Library of Medicine HSDB Database".
  72. ^ Jump up to: a b Stasik, M.; Byczkowska, Z.; Szendzikowski, S.; Fiedorczuk, Z. (December 1969). "Acute tetraethyllead poisoning". Archiv für Toxikologie. 24 (4): 283–291. doi:10.1007/BF00577576 (inactive 31 May 2021). PMID 5795752.CS1 maint: DOI inactive as of May 2021 (link)
  73. ^ Le Quesne, P. M. (1981). "Toxic substances and the nervous system: the role of clinical observation". Journal of Neurology, Neurosurgery & Psychiatry. 44 (1): 1–8. doi:10.1136/jnnp.44.1.1. PMC 490811. PMID 7009792.
  74. ^ "Fact sheet" (PDF). nj.gov. Retrieved 11 November 2019.
  75. ^ Finkelstein, Yoram (July 1998). "Low-level lead-induced neurotoxicity in children: an update on central nervous system effects". Brain Research Reviews. 27 (2): 168–176. doi:10.1016/S0165-0173(98)00011-3. PMID 9622620. S2CID 15666676.
  76. ^ Jump up to: a b c Reyes, J. W. (2007). "The Impact of Childhood Lead Exposure on Crime". National Bureau of Economic Research. "a" ref citing Pirkle, Brody, et. al (1994). Retrieved 17 August 2009.
  77. ^ Löwig (1853) "Ueber Methplumbäthyl" (On meta-lead ethyl) Annalen der Chemie und Pharmacie, 88 : 318-322.
  78. ^ George Bowdler Buckton (1859) "Further remarks on the organo-metallic radicals, and observations more particularly directed to the isolation of mercuric, plumbic, and stannic ethyl," Proceedings of the Royal Society of London, 9 : 309-316. For Buckton's preparation of tetraethyl lead, see pages 312-314.
  79. ^ See, for example:
    • H. E. Roscoe and C. Schorlemmer, A Treatise on Chemistry, Volume 3, Part 1 (New York, New York: D. Appleton and Co., 1890), page 466.
    • Frankland and Lawrence credit Buckton with synthesizing tetraethyl lead in: E. Frankland and Awbrey Lawrance (1879) "On plumbic tetrethide," Journal of the Chemical Society, Transactions, 35 : 244-249.
  80. ^ "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
  81. ^ zk4540. "Innovation Starts Here – DuPont USA".
  82. ^ Blum, Deborah (5 January 2013). "Looney Gas and Lead Poisoning: A Short, Sad History". Wired – via www.wired.com.
  83. ^ Harford, Tim (28 August 2017). "Why did we use leaded petrol for so long?". BBC News. Retrieved 3 September 2017.
  84. ^ "Tetraethyl lead(Bruce Hamilton)". yarchive.net.
  85. ^ Alan P. Loeb, "Paradigms Lost: A Case Study Analysis of Models of Corporate Responsibility for the Environment," Business and Economic History, Vol. 28, No. 2, Winter 1999, at 95.
  86. ^ Silbergeld, Ellen (February 1995). "Annotation: Protection of the Public Interest, Allegations of Scientific Misconduct, and the Needleman Case". American Journal of Public Health. 85 (2): 165–166. doi:10.2105/AJPH.85.2.165. PMC 1615323. PMID 7856774.
  87. ^ Bryson, Christopher (2004). The Fluoride Deception, p. 41. Seven Stories Press. Citing historian Lynne Snyder.
  88. ^ Bryson, B. (2003). "10. Getting the Lead Out". A Short History of Nearly Everything. New York: Broadway Books. ISBN 978-0-7679-0818-4.
  89. ^ Needleman, H. (2000). "The Removal of Lead from Gasoline: Historical and Personal Reflections". Environmental Research. 84 (1): 20–35. Bibcode:2000ER.....84...20N. doi:10.1006/enrs.2000.4069. PMID 10991779.
  90. ^ "Lead Credit Trading". National Center for Environmental Economics. US EPA. c. 2006. Retrieved 3 October 2014.
  91. ^ Pirkle, J.L.; Brody, D.J.; Gunter, E.W.; et al. (1994). "The Decline in Blood Lead Levels in the United States: The National Health and Nutrition Examination Surveys (NHANES)". JAMA. 272 (4): 284–291. doi:10.1001/jama.1994.03520040046039. PMID 8028141.
  92. ^ Pirisi, Angela (9 April 2005). "Profile Philip Landrigan: children's health crusader" (PDF). The Lancet. 365: 1301.
  93. ^ "EPA Takes Final Step in Phaseout of Leaded Gasoline". US EPA Archive. US EPA. 29 January 1996. Retrieved 5 January 2020. Effective 1 January 1996, the Clean Air Act banned the sale of the small amount of leaded fuel that was still available in some parts of the country for use in on-road vehicles. EPA said fuel containing lead may continue to be sold for off-road uses, including aircraft, racing cars, farm equipment, and marine engines.
  94. ^ Schnaas, Lourdes; Rothenberg, Stephen J.; Flores, María-Fernanda; Martínez, Sandra; Hernández, Carmen; Osorio, Erica; Perroni, Estela (2004). "Blood Lead Secular Trend in a Cohort of Children in Mexico City (1987–2002)". Environ. Health Perspect. 112 (10): 1110–1115. doi:10.1289/ehp.6636. PMC 1247386. PMID 15238286.
  95. ^ Paulina Pino, Tomás Walter; Manuel J. Oyarzún A3, Matthew J. Burden; Betsy Lozoff (2004). "Rapid Drop in Infant Blood Lead Levels during the Transition to Unleaded Gasoline Use in Santiago, Chile". Archives of Environmental Health. 59 (4): 182–187. doi:10.3200/AEOH.59.4.182-187. PMID 16189990. S2CID 25089958.CS1 maint: multiple names: authors list (link)
  96. ^ Valerie Franchi, "Getting the Lead Out," Front Lines, published by the U.S. Agency for International Development, Oct. 1997.
  97. ^ "The Case for Banning Lead in Gasoline" (PDF). Manufacturers of Emission Controls Association (MECA). January 2003. Archived from the original (PDF) on 26 April 2012. Retrieved 7 June 2012.
  98. ^ Tsai, P.L.; Hatfield, T.H. (December 2011). "Global Benefits From the Phaseout of Leaded Fuel" (PDF). Journal of Environmental Health. 74 (5): 8–14.
  99. ^ "Highly polluting leaded petrol now eradicated from the world, says UN". BBC News. 31 August 2021.
  100. ^ "Era of leaded petrol over, eliminating a major threat to human and planetary health". United Nations Environment Programme. Retrieved 31 August 2021.
  101. ^ Matthews, Dylan (22 April 2013). "Lead abatement, alcohol taxes and 10 other ways to reduce the crime rate without annoying the NRA". The Washington Post. Retrieved 23 May 2013.
  102. ^ Lean, Geoffrey (27 October 2007). "Ban on leaded petrol 'has cut crime rates around the world'". The Independent.
  103. ^ Chicago Tribune (6 June 2015). "Lead poisoning linked to violent crime – Chicago Tribune". chicagotribune.com.
  104. ^ Wolpaw Reyes, Jessica (May 2007). "Environmental Policy as Social Policy? The Impact of Childhood Lead Exposure on Crime" (PDF). National Bureau of Economic Research. Retrieved 23 May 2013.
  105. ^ Drum, Kevin (January–February 2013). "America's Real Criminal Element: Lead". Mother Jones. Retrieved 4 January 2013.
  106. ^ "Lead's Urban Legacy". Tulane University. 2013. Retrieved 19 November 2019. Children and adults inadvertently touch, breath and eat lead-soil from inside and outside sources. Its accessability [sic] makes it a bigger lead-health threat than leaded paint...

Further reading[]

  • Filella, Montserrat; Bonet, Josep (2017). "Chapter 14. Environmental Impact of Alkyl Lead(IV) Derivatives: Perspective after Their Phase-out". In Astrid, S.; Helmut, S.; Sigel, R. K. O. (eds.). Lead: Its Effects on Environment and Health. Metal Ions in Life Sciences. 17. de Gruyter. pp. 471–490. doi:10.1515/9783110434330-014. ISBN 978-3-11-043433-0. PMID 28731307.

External links[]

Retrieved from ""