Outdoor & Yard / Compounds / Tetraethyl lead (TEL)

Tetraethyl lead (TEL) in the yard and garden

High risk for your yard

Tetraethyl lead (TEL, lead tetraethyl) was the primary antiknock additive in leaded gasoline from 1923 until its global phase-out (US ban phased 1973–1996; global fuel lead standards largely achieved by 2021 with Algeria as the last country eliminating leaded petrol). TEL was introduced by Charles Kettering and Thomas Midgley Jr. at General Motors, who also suppressed early evidence of its neurotoxicity from corporate researchers at the Ethyl Corporation in the 1920s. TEL is lipid-soluble and volatilizes from gasoline readily; inhalation was the primary occupational and environmental exposure route. TEL is far more acutely toxic than inorganic lead compounds: it is directly toxic to the CNS as the organic form, independent of its conversion to inorganic lead, producing an acute neuropsychiatric syndrome (tremors, insomnia, hallucinations, psychosis, and death) at high exposures. Workers at TEL manufacturing plants in the 1920s experienced mass poisonings (the Standard Oil 'loony gas' incidents of 1924) with deaths and permanent neurological injury. TEL decomposes in the atmosphere and soil to inorganic lead, representing the dominant pathway by which leaded gasoline contaminated urban soils and air for seven decades. Blood lead levels in the US population declined approximately 78% between 1976 and 1991 following the leadedgasoline phase-out — one of the largest public health achievements of the 20th century. Residual TEL-derived inorganic lead contamination persists in soil along historical roadways and in urban environments globally.

What is tetraethyl lead (tel)?

The IUPAC name is tetraethylplumbane.

Also known as: tetraethylplumbane, Tetraethyllead, Plumbane, tetraethyl-, TETRAETHYL LEAD.

IUPAC name
tetraethylplumbane
CAS number
78-00-2
Molecular formula
C8H20Pb
Molecular weight
323.0 g/mol
SMILES
CC[Pb](CC)(CC)CC
PubChem CID
6511

Risk for people, pets,

High risk

Tetraethyl lead (TEL, lead tetraethyl) was the primary antiknock additive in leaded gasoline from 1923 until its global phase-out (US ban phased 1973–1996; global fuel lead standards largely achieved by 2021 with Algeria as the last country eliminating leaded petrol). TEL was introduced by Charles Kettering and Thomas Midgley Jr. at General Motors, who also suppressed early evidence of its neurotoxicity from corporate researchers at the Ethyl Corporation in the 1920s. TEL is lipid-soluble and volatilizes from gasoline readily; inhalation was the primary occupational and environmental exposure route. TEL is far more acutely toxic than inorganic lead compounds: it is directly toxic to the CNS as the organic form, independent of its conversion to inorganic lead, producing an acute neuropsychiatric syndrome (tremors, insomnia, hallucinations, psychosis, and death) at high exposures. Workers at TEL manufacturing plants in the 1920s experienced mass poisonings (the Standard Oil 'loony gas' incidents of 1924) with deaths and permanent neurological injury. TEL decomposes in the atmosphere and soil to inorganic lead, representing the dominant pathway by which leaded gasoline contaminated urban soils and air for seven decades. Blood lead levels in the US population declined approximately 78% between 1976 and 1991 following the leadedgasoline phase-out — one of the largest public health achievements of the 20th century. Residual TEL-derived inorganic lead contamination persists in soil along historical roadways and in urban environments globally.

Regulatory consensus

5 regulatory and scientific bodies have classified Tetraethyl lead (TEL). The classifications differ — that's the data.

AgencyYearClassificationNotes
EPA CTX / NTP RoCReasonably Anticipated to be a Human Carcinogen
EPA CTX / GenetoxGenotoxicity: negative (Ames: negative, 1 positive / 4 negative reports)
EPA CTX / GenetoxGenotoxicity: negative (Ames: negative, 1 positive / 4 negative reports)
EPA CTX / Skin-EyeEye Irritation: Category 6.4A (Category 2A) (score: high)
EPA CTX / Skin-EyeSkin Irritation: Category 6.3A (Category 2) (score: high)

Regulators apply different standards of evidence — animal-data weighting, exposure-pattern assumptions, epidemiological power thresholds — which is why two scientific bodies can review the same data and reach different conclusions. The disagreement is the data.

Where your yard encounter tetraethyl lead (tel)

  • Contaminated WaterMining site runoff, Industrial discharge areas, Drinking water from old infrastructure
  • Soil ContaminationIndustrial sites, Smelter areas, Battery recycling facilities
  • Food ChainFish from contaminated waters, Shellfish from polluted areas, Crops grown in contaminated soil

Safer alternatives

Lower-risk approaches that achieve a similar outcome to Tetraethyl lead (TEL):

  • Safer process chemistry; Green chemistry alternatives; Exposure controls
    Trade-offs: Requires R&D investment to redesign synthesis routes; may reduce yield or throughput initially; long-term benefits include reduced waste treatment costs, regulatory compliance, and worker safety; 12 Principles of Green Chemistry framework available.
    Relative cost: 2-5×

Frequently asked questions

Is tetraethyl lead (tel) safe for your yard?

Tetraethyl lead (TEL, lead tetraethyl) was the primary antiknock additive in leaded gasoline from 1923 until its global phase-out (US ban phased 1973–1996; global fuel lead standards largely achieved by 2021 with Algeria as the last country eliminating leaded petrol). TEL was introduced by Charles Kettering and Thomas Midgley Jr. at General Motors, who also suppressed early evidence of its neurotoxicity from corporate researchers at the Ethyl Corporation in the 1920s. TEL is lipid-soluble and volatilizes from gasoline readily; inhalation was the primary occupational and environmental exposure route. TEL is far more acutely toxic than inorganic lead compounds: it is directly toxic to the CNS as the organic form, independent of its conversion to inorganic lead, producing an acute neuropsychiatric syndrome (tremors, insomnia, hallucinations, psychosis, and death) at high exposures. Workers at TEL manufacturing plants in the 1920s experienced mass poisonings (the Standard Oil 'loony gas' incidents of 1924) with deaths and permanent neurological injury. TEL decomposes in the atmosphere and soil to inorganic lead, representing the dominant pathway by which leaded gasoline contaminated urban soils and air for seven decades. Blood lead levels in the US population declined approximately 78% between 1976 and 1991 following the leadedgasoline phase-out — one of the largest public health achievements of the 20th century. Residual TEL-derived inorganic lead contamination persists in soil along historical roadways and in urban environments globally.

What products contain tetraethyl lead (tel)?

Tetraethyl lead (TEL) appears in: Mining site runoff (Contaminated water); Industrial discharge areas (Contaminated water); Industrial sites (Soil contamination); Smelter areas (Soil contamination); Fish from contaminated waters (Food chain).

Why do regulators disagree about tetraethyl lead (tel)?

Tetraethyl lead (TEL) has been classified by 5 agencies including EPA CTX / NTP RoC, EPA CTX / Genetox, EPA CTX / Genetox, EPA CTX / Skin-Eye, EPA CTX / Skin-Eye, with differing conclusions. Regulators apply different standards of evidence (animal data weighting, exposure-pattern assumptions, epidemiological power thresholds), which is why two scientific bodies can review the same data and reach different conclusions. See the regulatory consensus table on this page for the full picture.

See Tetraethyl lead (TEL) in the outdoor app

Look up products containing tetraethyl lead (tel), compare to alternatives, and explore the full data record.

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Sources (3)

  1. Needleman et al.: Deficits in Psychologic and Classroom Performance of Children with Elevated Dentine Lead Levels — NEJM Leaded Gasoline IQ Study (1979) — study
  2. ATSDR Toxicological Profile: Lead — TEL Antiknock Additive History, Gasoline Phase-out, Blood Lead Decline, Neurocognitive Effects, Soil Legacy Contamination (2020) — regulatory
  3. US EPA: Leaded Gasoline Phase-out Final Rule — Complete Ban Effective January 1, 1996; Blood Lead Trend Data; Environmental Lead Burden Reduction (1996) — regulatory

Reference data, not professional advice. Aggregates publicly available regulatory and scientific data; not a substitute for veterinary, medical, legal, or regulatory advice. Why we built ALETHEIA →