Agent Name |
Naphthalene |
CAS Number |
91-20-3 |
Formula |
C10-H8 |
Major Category |
Other Classes |
Synonyms |
Naphthalin; Tar camphor; White tar; [NIOSH] |
Category |
Naphthalenes |
Description |
Colorless to brown solid with an odor of mothballs. [Note: Shipped as a molten solid.] [NIOSH] |
Sources/Uses |
Naphthalene is produced from petroleum or coal tars. Naphthalene is used mainly as an intermediate in the synthesis of other organic chemicals. It is used as a household moth repellent. [ACGIH] Naphthalene is produced from incomplete combustion, e.g., burning fossil fuels, forest fires, and smoking cigarettes. It is present in jet and diesel fuel. Its use as a moth repellent has decreased since the introduction of p-dichlorobenzene. Naphthalene is one of the major components of creosote, and the highest concentrations in industrial environments occur in workplaces producing creosote-impregnated timbers. [See Reference #1] |
Comments |
Naphthalene is an ocular irritant that has caused cataracts in exposed workers. Inhaled naphthalene can induce methemoglobinemia and precipitate subacute hemolysis. Workers deficient in glucose-6-phosphate dehydrogenase are more susceptible to hemolysis. [ACGIH] Liver changes were seen in rats after10 days of oral administration. [HSDB] Naphthalene is not hepatotoxic in experimental animal studies or in human exposures. [Zimmerman, p. 367] Hemolytic anemia and jaundice have been reported after ingestion. [CHEMINFO] See the disease, "Hemolytic anemia, subacute." |
Reference Link |
Naphthalene--an environmental and occupational toxicant. |
Exposure Assessment |
Skin Designation (ACGIH) |
Yes |
TLV (ACGIH) |
10 ppm |
STEL (ACGIH) |
15 ppm |
PEL (OSHA) |
10 ppm |
IDLH (NIOSH) |
250 ppm |
Excerpts from Documentation for IDLHs |
Human data: The probable oral lethal dose has been reported to be between 5 and 15 grams [Gerarde 1960]. [Note: An oral dose between 5 and 15 grams is equivalent to a worker being exposed to about 600 to 1,800 ppm for 30 minutes, assuming a breathing rate of 50 liters per minute and 100% absorption.] |
Vapor Pressure |
0.08 mm Hg |
Odor Threshold Low |
0.0095 ppm |
Odor Threshold High |
0.64 ppm |
Explanatory Notes |
Detection odor threshold from AIHA (mean = 0.038 ppm); |
Half Life |
Whole body: 8 days; [TDR, p. 909] |
Reference Link |
ATSDR - ToxFAQs - Naphthalene |
Flammability (NFPA) |
2: high ambient temperature required |
Adverse Effects |
Methemoglobinemia |
Methemoglobinemia, Secondary |
Hepatotoxin |
Hepatotoxin, Secondary |
IARC Carcinogen |
Possible Carcinogen |
Links to Other NLM Databases |
Health Studies |
Human Health Effects from Hazardous Substances Data Bank: NAPHTHALENE
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