CAS number. . . . . . . . . . . 7726-95-6 NIOSH REL . . . . . . . . . . . 0.1 ppm (0.7 mg/m3) TWA, 0.3 ppm (2 mg/m3) STEL Current OSHA PEL. . . . . . . . 0.1 ppm (0.7 mg/m3) TWA 1989 OSHA PEL . . . . . . . . . 0.1 ppm (0.7 mg/m3) TWA, 0.3 ppm (2 mg/m3) STEL 1993-1994 ACGIH TLV . . . . . . 0.1 ppm (0.66 mg/m3) TWA, 0.3 ppm (2.0 mg/m3) STEL Description of Substance. . . . Dark reddish-brown, fuming liquid with suffocating, irritating fumes. LEL . . . . . . . . . . . . . . Noncombustible Liquid Original (SCP) IDLH . . . . . . 10 ppm Basis for original (SCP) IDLH . The chosen IDLH is based on the statement by AIHA [1958] that concentrations of 10 ppm or above cause such severe upper respiratory irritation that such concentrations will not be voluntarily borne [MCA 1968]. AIHA [1958] also reported that even brief exposures of 40 to 60 ppm are dangerous for humans [Henderson and Haggard 1943]. Short-term exposure guidelines. None developed
Lethal concentration data:
Adjusted LC50 LCLo 0.5-hr Derived Species Reference (ppm) (ppm) Time LC (CF*) Value ______________________________________________________________________________ Mouse Bitron and Aharonson 750 ----- 9 min 435 ppm (0.58) 44 ppm 1978 Mouse Bitron and Sharonson 240 ----- 2 hr 451 ppm (1.88) 45 ppm 1978 Rat Ivanov et al. 1976 407 ----- ? ? ? Rabbit Spector 1955 ----- 180 6.5 hr 578 ppm (3.21) 58 ppm
*Note: Conversion factor (CF) was determined with "n" = 2.2 [ten Berge et al. 1986]. Lethal dose data:
LD50 LDLo Derived Species Reference Route (mg/kg) (mg/kg) Adjusted LD Value ______________________________________________________________________________ Rat Gig Sanit 1970 oral 2,600 ----- 2,741 ppm 274 ppm Mouse Gig Sanit 1970 oral 3,100 ----- 3,268 ppm 327 ppm Rabbit Gig Sanit 1970 oral 4,160 ----- 4,386 ppm 439 ppm G. pig Gig Sanit 1970 oral 5,500 ----- 5,798 ppm 580 ppm
Human data. . . . . . . . . . . It has been reported that 10 ppm and above cause such severe upper respiratory irritation that exposures will not be voluntarily borne [MCA 1968]. Also, it has been reported that 0.75 ppm caused no symptoms in 6 hours [Flury and Zernik 1931]. Further, 4 ppm has been recommended as the maximum concentration allowable for 0.5 to 1 hour, with 40 to 60 ppm dangerous for brief exposures [Henderson and Haggard 1943]. It has also been stated that respiratory damage occurs at 10 ppm [NFPA 1978]. It has been reported that 1.7 to 3.5 ppm produces severe choking, 4.5 to 9 ppm is extremely dangerous, and 30 ppm would prove fatal in a short time [ILO 1971].
Revised IDLH: 3 ppm
Basis for revised IDLH: The revised IDLH for bromine is 3 ppm based on acute
inhalation toxicity data in humans [Flury and Zernik 1931; Henderson and
Haggard 1943; ILO 1971; MCA 1968; NFPA 1978].