Boron trifluoride

CAS number . . . . . . . . . . . 7637-07-2
NIOSH REL. . . . . . . . . . . . 1 ppm (3 mg/m3) CEILING
Current OSHA PEL . . . . . . . . 1 ppm (3 mg/m3) CEILING
1989 OSHA PEL. . . . . . . . . . Same as current PEL
1993-1994 ACGIH TLV. . . . . . . 1 ppm (2.8 mg/m3) CEILING
Description of Substance . . . . Colorless gas with a pungent, suffocating
                                 odor.
LEL .. . . . . . . . . . . . . . Nonflammable Gas
Original (SCP) IDLH. . . . . . . 100 ppm
Basis for original (SCP) IDLH. . Because no useful data on acute inhalation
                                 toxicity are available on which to base the
                                 IDLH, the chosen IDLH is based on chronic
                                 toxicity data (i.e., repeated exposure to 100
                                 ppm resulted in a uniformly high mortality
                                 rate in six laboratory species [Stokinger
                                 et al. 1953 cited by ACGIH 1971]).  The only
                                 acute inhalation toxicity data available was
                                 not used to establish the IDLH because
                                 in 5.5 hours 10 of 10 guinea pigs succumbed
                                 to an exposure of 750 ppm [Livinskas 1964].
Short-term exposure guidelines . None developed

ACUTE TOXICITY DATA

Lethal concentration data:

                                                         Adjusted             
                                 LC50   LCLo              0.5-hr       Derived
Species     Reference            (ppm)  (ppm)  Time       LC (CF)       Value
______________________________________________________________________________
Mouse    Farmakol Toksikol 1972  1,227  -----  2 hr   1,963 ppm (1.6)  196 ppm
G. pig   Farmakol Toksikol 1972     39  -----  4 hr      77 ppm (2.0)    8 ppm
Rat      Izmerov et al. 1982       418  -----  4 hr     837 ppm (2.0)   84 ppm

                                  
Other animal data. . . . . . . . Exposure to a concentration of 100 ppm
                                 resulted in a uniformly high mortality rate
                                 in six laboratory species, and 15 ppm was
                                 occasionally fatal in 30-day studies
                                 [Stokinger et al. 1953].  Rats exposed 6
                                 hours/day to 24 ppm or 2 weeks to 9 ppm
                                 showed signs of respiratory irritation,
                                 depression of body weight, increased
                                 lung weights, and depressed liver weights
                                 [Rusch et al. 1986].
Human data . . . . . . . . . . . None relevant for use in determining the
                                 revised IDLH.

Revised IDLH: 25 ppm
Basis for revised IDLH: The revised IDLH for boron trifluoride is 25 ppm based on subchronic inhalation toxicity data in animals [Rusch et al. 1986].

REFERENCES:

1. ACGIH [1971]. Boron trifluoride. In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 26-27.
2. Farmakol Toksikol [1972]; 35:369-372 (in Russian).
3. Izmerov NF, Sanotsky IV, Sidorov KK [1982]. Toxicometric parameters of industrial toxic chemicals under single exposure. Moscow, Russia: Centre of International Projects, GKNT, p. 27.
4. Livinskas GJ [1964]. In: Adams RM, ed. Boron metallo-boron compounds and boranes, New York, NY: Interscience Publishers, Inc.
5. Rusch GM, Hoffman GM, McConnell RF, Rinehart WE [1986]. Inhalation toxicity studies with boron trifluoride. Toxicol Appl Pharmacol 83:69-78.
6. Stokinger HE, Spiegl CJ, et al. [1953]. Chapter 28. Special materials. In: Voegtlin C, Hodge HC, eds. Pharmacology and toxicology of uranium compounds, chronic inhalation and other studies. Vol. 4. New York, NY: McGraw-Hill Book Company, Inc., p. 2302.