Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 91–20–3
NIOSH REL: 10 ppm (50 mg/m3) TWA, 15 ppm (75 mg/m3) STEL
Current OSHA PEL: 10 ppm (50 mg/m3) TWA
1989 OSHA PEL: 10 ppm (50 mg/m3) TWA, 15 ppm (75 mg/m3) STEL
1993-1994 ACGIH TLV: 10 ppm (52 mg/m3) TWA, 15 ppm (79 mg/m3) STEL
Description of substance: Colorless to brown solid with an odor of mothballs.
LEL: . . . 0.9% (10% LEL, 900 ppm)
Original (SCP) IDLH: 500 ppm
Basis for original (SCP) IDLH: No useful data on acute inhalation toxicity are available on which to base the IDLH for naphthalene. The chosen IDLH, therefore, has been estimated from the probable oral lethal dose of 5 to 15 grams for an adult [Gerarde 1960 cited by AIHA 1967].
Short-term exposure guidelines: None developed
ACUTE TOXICITY DATA:
Lethal dose data:
|Species||Reference||Route||LD50(mg/kg)||LDLo(mg/kg)||Adjusted LD||Derived value|
|Gosselin et al. 1984Izmerov et al. 1982
Shopp et al. 1984
|2,355 ppm641 ppm
|236 ppm64 ppm
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.]
|Revised IDLH: 250 ppmBasis for revised IDLH: No inhalation toxicity data are available on which to base an IDLH for naphthalene. Therefore, the revised IDLH for naphthalene is 250 ppm based on acute oral toxicity data in humans [Gerarde 1960].|
1. AIHA . Naphthalene. In: Hygienic guide series. Am Ind Hyg Assoc J 28:493-496.
2. Gerarde HW . Toxicology and biochemistry of aromatic hydrocarbons. Princeton, NJ: Elsevier Publishing Company, p. 228.
3. Gosselin RE, Smith RP, Hodge HC . Clinical toxicology of commercial products. 5th ed. Section III. Therapeutics Index. Baltimore, MD: Williams & Wilkins Company, pp. 307-310.
4. Izmerov NF, Sanotsky IV, Sidorov KK . Toxicometric parameters of industrial toxic chemicals under single exposure. Moscow, Russia: Centre of International Projects, GKNT, p. 89.
5. Matorova NI . Data on establishing the maximum permissible concentration of naphthalene and chloronaphthalene in reservoir water. Gig Sanit 11:78-79 (in Russian).
6. Shopp GM, White KL Jr, Holsapple MP, Barnes DW, Duke SS, Anderson AC, Condie LW, Hayes JR, Borzelleca JF . Naphthalene toxicity in CD-1 mice: general toxicology and immunotoxicology. Fundam Appl Toxicol 4:406-419.
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- Page last updated: December 4, 2014
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