Tetrahydrofuran

CAS number: 109–99–9

NIOSH REL: 200 ppm (590 mg/m³) TWA, 250 ppm (735 mg/m³) STEL

Current OSHA PEL: 200 ppm (590 mg/m³) TWA

1989 OSHA PEL: 200 ppm (590 mg/m³) TWA, 250 ppm (735 mg/m³) STEL

1993-1994 ACGIH TLV: 200 ppm (590 mg/m³) TWA, 250 ppm (737 mg/m³) STEL

Description of substance: Colorless liquid with an ether-like odor.

LEL: . . . 2% (10% LEL, 2,000 ppm)

Original (SCP) IDLH: 20,000 ppm [LEL]

Basis for original (SCP) IDLH: AIHA [1959] reported that exposure to 25,000 ppm will cause anesthesia and that 17,000 ppm appears to be safe for 3 hours [Hofmann and Oettel 1954]. Therefore, 20,000 ppm has been chosen as the IDLH because it is the lower explosive limit (LEL) of tetrahydrofuran.

Short-term exposure guidelines: None developed

ACUTE TOXICITY DATA:

Lethal concentration data:

Species	Reference	LC50 (ppm)	LCLo (ppm)	Time	Adjusted 0.5-hr LC (CF)	Derived value
Rat	Horiguchi et al. 1984	21,000	-----	3 hr	37,800 ppm (1.8)	3,780 ppm

Lethal dose data:

Species	Reference	Route	LD50 (mg/kg)	LDLo (mg/kg)	Adjusted LD	Derived value
Rat Mouse G. pig	GAF 1991 Pozdnyakov 1967 Pozdnyakov 1967	oral oral oral	1,650 2,300 2,300	----- ----- -----	3,850 ppm 5,367 ppm 5,367 ppm	385 ppm 537 ppm 537 ppm

Human data: It has been reported that exposure to 25,000 ppm will cause anesthesia and 17,000 ppm appears to be safe for 3 hours [Hofmann and Oettel 1954].

Revised IDLH: 2,000 ppm [LEL] Basis for revised IDLH: Based on health considerations and acute inhalation toxicity data in humans [Hofmann and Oettel 1954], a value of at least 17,000 ppm would have been appropriate for tetrahydrofuran. However, the revised IDLH is 2,000 ppm based strictly on safety considerations (i.e., being 10% of the lower explosive limit of 2%).

REFERENCES:

1. AIHA [1959]. Tetrahydrofuran. In: Hygienic guide series. Am Ind Hyg Assoc J 20:250-251.

2. GAF [1991]. Material safety data sheet: Agrisynth THF. Wayne, NJ: GAF Chemicals Corporation, pp. 1-3.

3. Hofmann G, Oettel H [1954]. Zur frage der toxizitat von tetrahydrofuran. Arch Exp Pathol Pharmakol 222:233-235 (in German).

4. Horiguchi S, Teramoto K, Katahira T [1984]. Acute and repeated inhalation toxicity of tetrahydrofuran in laboratory animals. Sumitomo Sangyo Eisei (Sumitomo Industrial Health) 20:141-157.

5. Pozdnyakov AG [1967]. Materials on hygienic reglamentation of tetrahydrofuryl (THF) alcohol in water bodies. Gig Sanit 32(2):99-101 (in Russian).