Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 86-88-4
NIOSH REL: 0.3 mg/m3 TWA
Current OSHA PEL: 0.3 mg/m3 TWA
1989 OSHA PEL: Same as current PEL
1993-1994 ACGIH TLV: 0.3 mg/m3 TWA
Description of substance: White crystalline or gray, odorless powder.
LEL: Noncombustible Solid
Original (SCP) IDLH: 100 mg/m3
Basis for original (SCP) IDLH: No useful acute inhalation toxicity data are available on which to base the IDLH for ANTU. The chosen IDLH, therefore, has been estimated from the fatal human oral dose of 1 gram given by Stolman . According to ACGIH , McClosky and Smith  reported that the acute oral toxicity varies greatly among different species, with rats and dogs being the most susceptible (LD50 of 30 to 50 mg/kg) and rabbits the least susceptible (LD50 of 1,000 mg/kg).
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|
|Dog||AAPCO 1966||oral||0.38||—–||2.7 mg/m3||0.3 mg/m3|
|Rat||Lehman 1952||oral||6||—–||42 mg/m3||4.2 mg/m3|
|Monkey||Perkow 1971/76||oral||4,250||—–||29,750 mg/m3||2,975 mg/m3|
|Mouse||Yakkyoku 1977||oral||5||—–||35 mg/m3||3.5 mg/m3|
Other animal data: It has been reported that the mean oral lethal dose is 4,000 mg/kg in monkeys and is presumably much the same in man [Gosselin et al. 1984].
Human data: The fatal oral dose has been reported to be 1,000 mg [Stolman 1969]. [Note: An oral dose of 1,000 mg is equivalent to a worker being exposed to 650 mg/m3 for 30 minutes, assuming a breathing rate of 50 liters per minute and 100% absorption.]
Revised IDLH: 100 mg/m3 [Unchanged]
Basis for revised IDLH: No inhalation toxicity data are available on which to base an IDLH for ANTU. However, based on acute oral toxicity data in humans [Stolman 1969] and animals [Gosselin et al. 1984; Perkow 1971/76], the original IDLH for ANTU (100 mg/m3) is not being revised at this time.
- AAPCO . Pesticide chemicals official compendium. Topeka, KS: Association of American Pesticide Control Officials, Inc., p. 57.
- ACGIH . ANTU (alpha-naphthyl-thiourea). In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 15-16.
- Gosselin RE, Smith RP, Hodge HC . Clinical toxicology of commercial products. 5th ed. Section III. Baltimore, MD: Williams and Wilkins Company, pp. 40-42.
- Lehman AJ . Chemicals in foods: a report to the Association of Food and Drug Officials on current developments. Part II. Pesticides. Section III. Subacute and chronic toxicity. Q Bulletin Assoc Food Drug Off U.S. 16:47-53.
- McClosky WT, Smith MI . Studies on the pharmacologic action and the pathology of alpha-naphthylthiourea (ANTU). I. Pharmacology. Public Health Rep 60(38):1101-1113.
- Perkow W [1971/76]. Wirksubstanzen der pflanzenschutz und schadlingsbekampfungsmittel. Berlin, Germany: Verlag Paul Parey (in German).
- Stolman A, ed. . Progress in chemical toxicology. Vol. 4. New York, NY: Academic Press, p. 235.
- Yakkyoku (Pharmacy) ; 28:329-335 (in Japanese).