Beryllium compounds (as Be)

CAS number. . . . . . . . . . .  7440-41-7 (Metal)
NIOSH REL . . . . . . . . . . .  Not to exceed 0.0005 mg/m3; NIOSH considers
                                 beryllium compounds to be potential
                                 occupational carcinogens as defined by
                                 the OSHA carcinogen policy [29 CFR 1990].
Current OSHA PEL. . . . . . . .  0.002 mg/m3 TWA, 0.005 mg/m3 CEILING,
                                 0.025 mg/m3 30-minute MAXIMUM PEAK
1989 OSHA PEL . . . . . . . . .  Same as current PEL
1993-1994 ACGIH TLV . . . . . .  0.002 mg/m3 TWA, A2
Description of Substance. . . .  Varies
Original (SCP) IDLH*. . . . . .  10 mg Be/m3 [*Note:  "Effective" IDLH = 4 mg
                                 Be/m3 -- see discussion below.]
Basis for original (SCP) IDLH .  This IDLH is based on the statement by Patty
                                 [1963] that 10 mg/m3 of beryllium fluoride
                                 was lethal to several species in 15 days.
                                 However, respirators have been assigned on
                                 the basis of the assigned protection factor
                                 afforded by each device up to 2,000 x the
                                 OSHA PEL of 0.002 mg/m3 (i.e., 4 mg/m3); only
                                 the "most protective" respirators are
                                 permitted for use in concentrations exceeding
                                 4 mg Be/m3.
Short-term exposure guidelines.  None developed

ACUTE TOXICITY DATA

Lethal dose data:

                                                                              
                                  LD50    LDLo                      Derived
Species     Reference     Route  (mg/kg) (mg/kg)   Adjusted LD       Value
______________________________________________________________________________
BeF2:
 Rat     Blair 1951       oral      90    -----   158 mg Be/m3   16   mg Be/m3
 Mouse   Tabershaw 1972   oral     100    -----   161 mg Be/m3   16   mg Be/m3
BeSo4:
 Rat     Sazhina 1965     oral      82    -----    49 mg Be/m3    4.9 mg Be/m3
 Mouse   Sazhina 1965     oral      80    -----    48 mg Be/m3    4.8 mg Be/m3

Other animal data . . . . . . .  It has been reported that 10 mg/m3 of
                                 beryllium fluoride (i.e., 2.3 mg Be/m3) was
                                 lethal to several species in 15 days [Patty
                                 1963].
Human data. . . . . . . . . . .  None relevant for use in determining the
                                 revised IDLH.

Revised IDLH: 4 mg Be/m3
Basis for revised IDLH: Based on acute toxicity data in animals [Patty 1963; Sazhina 1965], a value of about 5 mg Be/m3 would have been appropriate. However, the revised IDLH for beryllium compounds is 4 mg Be/m3 based on being 2,000 times the OSHA PEL of 0.002 mg Be/m3 (2,000 is an assigned protection factor for respirators; only the "most reliable" respirators are recommended for exposures greater than 2,000 times the OSHA PEL). [Note: NIOSH recommends as part of its carcinogen policy that the "most protective" respirators be worn for beryllium compounds at concentrations above 0.0005 mg Be/m3.]

REFERENCES:

1. Blair HA [1951]. Quarterly technical report (January 1, 1951 through March 31, 1951). Rochester, NY: University of Rochester, Research and Development Report UR-154, U.S. Atomic Energy Commission Contract W-7401-eng-49.
2. Patty FA, ed. [1963]. Industrial hygiene and toxicology. 2nd rev. ed. Vol. II. Toxicology. New York, NY: Interscience Publishers, Inc., p. 1006.
3. Sazhina LA [1965]. Experimental data to substantiate the maximum permissible concentration of beryllium in the water of reservoirs. Gig Sanit 30(1-3):169-176 (translated).
4. Tabershaw IR, ed. [1972]. The toxicology of beryllium. U.S. Public Health Service Publication 2173:23.