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n-Butyl mercaptan
May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 109–79–5
NIOSH REL: 0.5 ppm (1.8 mg/m3) 15-minute CEILING
Current OSHA PEL: 10 ppm (35 mg/m3) TWA
1989 OSHA PEL: 0.5 ppm (1.5 mg/m3) TWA
1993-1994 ACGIH TLV: 0.5 ppm (1.8 mg/m3) TWA
Description of Substance: Colorless liquid with a strong, garlic-, cabbage-, or skunk-like odor.
LEL: . . Unknown
Original (SCP) IDLH: 2,500 ppm
Basis for original (SCP) IDLH: The chosen IDLH is based on the mouse 4-hour LC50 of 2,500 ppm [Fairchild and Stokinger 1958] cited by ACGIH [1971]. It was also chosen to make the IDLH for butyl mercaptan consistent with the IDLH of 2,500 ppm for ethyl mercaptan, a compound with similar acute toxicity.
Short-term exposure guidelines: None developed
ACUTE TOXICITY DATA
Lethal concentration data:
| Species | Reference | LC50(ppm) | LCLo(ppm) | Time | Adjusted 0.5-hrLC (CF) | Derivedvalue |
|---|---|---|---|---|---|---|
| RatMouse
Dog |
Fairchild and Stokinger 1958Fairchild and Stokinger 1958
Marhold 1986 |
4,0202,500
770 |
———-
—– |
4 hr4 hr
30 min |
8,040 ppm (2.0)5,000 ppm (2.0)
770 ppm (1.0) |
804 ppm500 ppm
77 ppm |
Human data: Accidental exposure for 1 hour to an estimated concentration of 50 to 500 ppm has been reported to cause muscular weakness, malaise, sweating, nausea, vomiting, headache, and confusion [Gobbato and Terribile 1968].
| Revised IDLH: 500 ppmBasis for revised IDLH: The revised IDLH for n-butyl mercaptan is 500 ppm based on acute inhalation toxicity data in workers [Gobbato and Terribile 1968] and animals [Fairchild and Stokinger 1958], and to be consistent with ethyl mercaptan which has a revised IDLH of 500 ppm. |
REFERENCES:
1. ACGIH [1971]. n-Butyl mercaptan (n-butanethiol). In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, p. 34.
2. Fairchild EJ II, Stokinger HE [1958]. Toxicologic studies on organic sulfur compounds. I. Acute toxicity of some aliphatic and aromatic thiols (mercaptans). Am Ind Hyg Assoc J 19:171-189.
3. Gobbato F, Terribile PM [1968]. Toxicological properties of mercaptans. Folia Medica 51:329-341. [From ACGIH [1991]. n-Butyl mercaptan. In: Documentation of the threshold limit values and biological exposure indices. 6th ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 183-184.]
4. Marhold J [1986]. Prehled prumyslove toxikologie: organicke latky. Prague, Czechoslovakia: Avicenum, p. 982 (in Czechoslovakian).