UN Number: 2304 - CAS Number: 91-20-3

Also known as: Naphthalin, Naphthene, Tar Camphor, White Tar, Naphthalene, Naphtalene
Information on chemical

Information on chemical

External resources

CAMEO Chemical Database
WISER Substance List


UN number 2304
CAS number 91-20-3
Formula C10H8

Physical chemical data

Physical State (20°C) Solid
Physical State (25°C) Solid
Density (kg/m3)
1140 [Kg/m³] at a temperature of 20°C
Kinematic viscosity (cSt)
0.96 [cSt] at a temperature of 20°C
Molar mass (g/mol) 128.18
Density of gas (kg/m3) 5.702
Solubility (g/L)
31 [g/L] at a temperature of 25°C and salinity of 0‰
23 [g/L] at a temperature of 25°C and salinity of 35‰
Boiling Point (°C) 218
Melting Point (°C) 80
Critical molar volume (m³/mol) 0.000407
Critical temperature (°C) 748.5
Critical pressure (Pa) 4050000
Surface tension (mN/m)
31.8 [mN/m] at a temperature of 20°C
Vapour Pressure (Pa)
130 [Pa] at a temperature of 20°C
10.5 [Pa] at a temperature of 25°C
Ignition Temperature (°C) 540
Flash Point (°C) 80
Flash Point (Pensky-Martens closed cup) (°C) 88
Flash Point (Cleveland open cup) (°C) 79
Lower explosivity limit (LEL) (volume %) 0.9
Upper explosivity limit (UEL) (volume %) 5.9
Vapor enthalpy (J/Kg)
337052 [J/Kg] at a temperature of 218°C
Combus enthalpy (J/Kg) 38900000
Specific heat capacity (J/(Kg·K)) 1292.8
Combustion efficiency (%) 70
Mass flow rate of the combustion surface (Kg/(m²·s)) 0.06
Rad fraction (%) 30
Henry's constant (mol/(m³·Pa)) 37.85

Behaviour at sea

Log kow 3.7
Log koc 3.13
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) 427

Additional data

Colour colourless
Odour mothball odour
MARPOL pollution category
Category Description
Other Substances Substances which have been evaluated and found to fall outside Category X, Y or Z because they are considered to present no harm to marine resources, human health, amenities or other legitimate uses of the sea when discharged into the sea from tank cleaning of deballasting operations. The discharge of bilge or ballast water or other residues or mixtures containing these substances are not subject to any requirements of MARPOL Annex II.

Transportation data

Transport mode Bulk,Packaged
Package group III
Cargo group 32
State liquid
Temperature (°C) elevated
Pressure (Pa) ambient
Family name aromatic hydrocarbons
IMO class 4.1

Reactivity data

Acid(s) Yes
Oxidizing agents Yes

GESAMP Hazard profile

Bioaccumulation in logPow (A1A) 3 - ≥3 and <4
Bioaccumulation in BCF (A1B) 3 - ≥100 and <500
Bioaccumulation (A1) 3 - Moderate potential to bioaccumulate
Biodegradation (A2) NR - Not readily biodegradable
Acute aquatic toxicity (B1) (LC/EC/IC50 (mg/l)) 4 - Highly toxic
Chronic aquatic toxicity (B2) (NOEC (mg/l)) 1 - Low
Acute mammalian toxicity by swallowing (C1) (LD50 (mg/kg)) 1 - Slight
Acute mammalian toxicity by skin penetration (C2) (LD50 (mg/kg)) 0 - Negligible
Acute mammalian toxicity by inhalation (C3) (LC50 (mg/l)) 2 - Moderate
Skin irritation/corrosivity (D1) 2 - Irritating
Eye irritation/corrosivity (D2) 1 - Mildly irritating
Interference with coastal amenities (E2) S - Sinking substance that would deposit on the seabed, not likely to dissolve quickly
Effects on wildlife and bottom habitats (E3) 3 - Is highly acutely toxic; and/or is severely irritant or corrosive to skin or eyes; and/or is carcinogenic, mutagenic or reprotoxic; and/or is a floater or persistent floater with associated health effects

Human toxicity threshold

Environmental Hazard Flammable Harmful Health Hazard
IDHL 500
Hazard statements
H228 Flammable solid.
H302 Harmful if swallowed.
H351 Suspected of causing cancer.
H410 Very toxic to aquatic life with long lasting effects.
Precautionary statements
P202 Do not handle until all safety precautions have been read and understood.
P234 Keep only in original container.
P270 Do no eat, drink or smoke when using this product.
P273 Avoid release to the environment.
P281 Use personal protective equipment as required.
P301 + P330 + P331 IF SWALLOWED: rinse mouth. Do NOT induce vomiting.
P303 + P361 + P353 IF ON SKIN (or hair): Remove/Take off immediately all contaminated clothing. Rinse skin with water/shower.
P305 + P351 + P338 IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
P308 + P313 IF exposed or concerned: Get medical advice/attention.
P370 + P378 In case of fire: Use ... for extinction.
P501 Dispose of contents/container to ...
TEEL-1 (mg/m3) 15 ppm
TEEL-2 (mg/m3) 15 ppm
TEEL-3 (mg/m3) 250 ppm


Lowest median lethal concentration (LC50) on algae (mg/l) 2.96
Lowest median lethal concentration (LC50) on crustacean (mg/l) 0.8
Lowest median lethal concentration (LC50) on fishes (mg/l) 1.6
Highest no observed effect concentration (NOEC) on algae (mg/l) > 4.3
Highest no observed effect concentration (NOEC) on crustacean (mg/l) 0.5
Highest no observed effect concentration (NOEC) on fishes (mg/l) 0.12
Assessment factor (AF)
100 on the Short term
100 on the Long term
Predicted No Effect Concentration (PNEC) (µg/l)
8 [µg/l] on the Short term
1.2 [µg/l] on the Long term
Incident reports

Incident reports

No incident reports available

Emergency Response Guidebook

Emergency Response Guidebook

Guide number: 133

See the guide or download the emergency response guidebook

At sea emergency guide

At sea emergency guide

Emergency schedule: 4.1-04


Emergency procedures

Spillage on deck

Stop leak if practicable using cold water. Contain molten products, if practicable, using inert material. Collect solid material for safe disposal.

Spillage under deck

Not applicable.

Fire on deck

Use water spray from as far away as practicable.

Fire under deck

Not applicable.

Special equipment to be carried

Protective clothing (gloves, boots, coveralls, headgear).
Self-contained breathing apparatus.
Spray nozzles.
Inert material.

Decision trees

Decision trees

No decision trees available

No additional data

last modified 2023-01-30T15:39:08+00:00

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