UN Number: 1993 - CAS Number: 100-51-6

Also known as: ALCOOL BENZYLIQUE, Tert-Butyl Ethyl Ether, 1,1-Dimethylethyl Ethyl Ether, 2-Ethoxy-2-Methylpropane, Ethyl 1,1-Dimethylethyl Ether, Ethyl Tert-Butyl Oxide, Methyl-2-Ethoxypropane, 2-Methyl-2-Ethoxypropane, Ethyl T-Butyl Ether, Ethyl Tert-Butyl Ether
Information on chemical

Information on chemical

External resources

CAMEO Chemical Database
WISER Substance List


UN number 1993
CAS number 100-51-6
Formula C6H14O

Physical chemical data

Physical State (20°C) Liquid
Physical State (25°C) Liquid
Density (kg/m3)
1050 [Kg/m³] at a temperature of 20°C
Molar mass (g/mol) 108.13
Density of gas (kg/m3) 4.773
Solubility (g/L)
12400 [g/L] at a temperature of 20°C and salinity of 0‰
13000 [g/L] at a temperature of 25°C and salinity of 0‰
Boiling Point (°C) 205
Melting Point (°C) -15
Critical molar volume (m³/mol) 0.000395
Critical temperature (°C) 509.4
Critical pressure (Pa) 2934000
Vapour Pressure (Pa)
13 [Pa] at a temperature of 20°C
20664.97 [Pa] at a temperature of 25°C
Ignition Temperature (°C) 435
Flash Point (°C) 101
Lower explosivity limit (LEL) (volume %) 1.3
Upper explosivity limit (UEL) (volume %) 1.3
Combus enthalpy (J/Kg) 36300000
Combustion efficiency (%) 96
Mass flow rate of the combustion surface (Kg/(m²·s)) 0.08
Rad fraction (%) 23
Henry's constant (mol/(m³·Pa)) 165.6

Behaviour at sea

Persistence (days) 1.6
Log kow 1.68
Log koc 2.29
Aqueous photolysis (Half-life) Not photolysable
Biodegradation in estuary environment (Half-life) (days) Not hydrolysable
Biodegradation in marine environment (Half-life) (days) Not biodegradable
Bioconcentration factor (BCF) 11.1

Additional data

Colour coulourless
Odour mild pleasant odour
MARPOL pollution category
Category Description
Y Noxious Liquid Substances which, if discharged into the sea from tank cleaning or deballasting operations, are deemed to present a hazard to either marine resources or human health or cause harm to amenities or other legitimate uses of the sea and therefore justify a limitation on the quality and quantity of the discharge into the marine environment.
Standard behavior classification SD

Transportation data

Transport mode Bulk,Packaged
State liquid
Temperature (°C) ambient
Pressure (Pa) ambient

Reactivity data

Water No
Acid(s) No
Base(s) No
Metal(s) and alloys No
Oxidizing agents No
Reducing agents No
Combustibles No
Organic substance No

GESAMP Hazard profile

Bioaccumulation in logPow (A1A) 1 - ≥1 and <2
Bioaccumulation (A1) 1 - Very low potential to bioaccumulate
Biodegradation (A2) R - Readily biodegradable
Acute aquatic toxicity (B1) (LC/EC/IC50 (mg/l)) 2 - Slightly toxic
Acute mammalian toxicity by swallowing (C1) (LD50 (mg/kg)) 1 - Slight
Acute mammalian toxicity by skin penetration (C2) (LD50 (mg/kg)) 1 - Slight
Acute mammalian toxicity by inhalation (C3) (LC50 (mg/l)) 2 - Moderate
Skin irritation/corrosivity (D1) 2 - Irritating
Eye irritation/corrosivity (D2) 2 - Irritating
Interference with coastal amenities (E2) SD - Sinker/Dissolver
Effects on wildlife and bottom habitats (E3) 2 - Is a persistent floater; and/or is moderately acutely toxic; and/or is irritating to skin and/or eyes; and/or has long-term health effects other than carcinogenicity, mutagenicity or reprotoxicity; and/or is highly flammable; and/or is flammable and is a floater with evaporative properties

Human toxicity threshold

Flammable Harmful
Hazard statements
H225 Highly flammable liquid and vapour.
H336 May cause drowsiness or dizziness.
Precautionary statements
P210 Keep away from heat/sparks/open flames/hot surfaces. No smoking.
P243 Take precautionary measures against static discharge.
P261 Avoid breathing dust/fume/gas/mist/vapours/spray.
P271 Use only outdoors or in a well-ventilated area.
P403 + P233 Store in a well-ventilated place. Keep container tightly closed.
TEEL-1 (mg/m3) 60
TEEL-2 (mg/m3) 150
TEEL-3 (mg/m3) 150


Lowest median lethal concentration (LC50) on algae (mg/l) 1100
Lowest median lethal concentration (LC50) on crustacean (mg/l) 37
Lowest median lethal concentration (LC50) on fishes (mg/l) 41.5
Highest no observed effect concentration (NOEC) on algae (mg/l) 7.5
Highest no observed effect concentration (NOEC) on crustacean (mg/l) 51
Highest no observed effect concentration (NOEC) on fishes (mg/l) 63.9
Assessment factor (AF)
1000 on the Short term
10000 on the Long term
Predicted No Effect Concentration (PNEC) (µg/l)
37 [µg/l] on the Short term
3.7 [µg/l] on the Long term
Incident reports

Incident reports

No incident reports available

Emergency Response Guidebook

Emergency Response Guidebook

Guide number: 128

See the guide or download the emergency response guidebook

At sea emergency guide

At sea emergency guide

No guides available

Decision trees

Decision trees

No decision trees available

No additional data

last modified 2023-01-30T15:44:34+00:00

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