Agent Name

Ethyl silicate

Alternative Name

Tetraethylorthosilicate

CAS Number

78-10-4

Formula

C8-H20-O4-Si

Major Category

Metals

Synonyms

Tetraethylorthosilicate; Dynasil A; ES 100; ES 28; ES 28 (ester); Ethyl orthosilicate; Ethyl silicate, ((EtO)4Si); Etylu krzemian [Polish]; Orthosilicic acid, tetraethyl ester; Silane, tetraethoxy-; Silicate d'ethyle [French]; Silicate tetraethylique [French]; Silicic acid, tetraethyl ester; Silicon ethoxide; Silicon tetraethoxide; Silikan L; TEOS; TEOS (VAN); Tetraethoxysilane; Tetraethoxysilicon; Tetraethyl orthosilicate; Tetraethyl silicate; Tetraethyl-O-silicate; Tetraethylsilikat [Czech]; [ChemIDplus] UN1292

Category

Metalloid Compounds (Silicon)

Description

Colorless liquid with a sharp, alcohol-like odor; [NIOSH]

Sources/Uses

Used in mortar and surface coatings to improve resistance to weather and chemical corrosion; [ACGIH] Used in the semiconductor/electronics industry; [CSH, p. 402] Used in castings for alloys with high melting points, copper alloys, and dental prosthetic devices; Also used as a source of silicon dioxide by vapor deposition and to produce refractory bricks and heat-resistant paints; [HSDB]

Comments

Rats that survived concentrations of 400 ppm for 7 hours/day for 30 days show liver, kidney, and lung damage. [ACGIH] Causes eye irritation at 250 ppm and tearing at 1,200 ppm; [CSH, p. 402] A skin and respiratory tract irritant; Liquid defats the skin and vapor may depress consciousness; [ICSC] In high-dose animal experiments, it acts as a general anesthetic; [ChemIDplus] See "Methyl silicate."

Exposure Assessment
Skin Designation (ACGIH)

Insufficient data

TLV (ACGIH)

10 ppm

PEL (OSHA)

100 ppm

MAK

10 ppm

IDLH (NIOSH)

700 ppm

Excerpts from Documentation for IDLHs

Human data: Exposure to a concentration of 1,200 ppm caused lacrimation and 250 ppm caused irritation of the eyes and nose [Smyth and Seaton 1940]. It has been stated that 700 ppm is probably intolerable for more than 30 minutes [Smyth and Seaton 1940].

Vapor Pressure

1.88 mm Hg

Odor Threshold Low

3.6 ppm

Lethal Concentration

LCLo (rat) = 1,000 ppm/4H

Explanatory Notes

Detection odor threshold from AIHA (mean = 3.6 ppm); Flash point = 99 deg F;

Flammability (NFPA)

3: May ignite at ambient temperature

Adverse Effects
Neurotoxin

Other CNS Neurotoxin

Hepatotoxin

Hepatotoxin, Secondary

Nephrotoxin

Yes

Links to Other NLM Databases
Health Studies

Human Health Effects from Hazardous Substances Data Bank:

Toxicity Information

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Chemical Information

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Related Information in HazMap
Processes

Industrial Processes with risk of exposure: