Acrylamide

CAS number . . . . . . . . . . . 79-06-1
NIOSH REL. . . . . . . . . . . . 0.03 mg/m3 TWA [skin]; NIOSH considers
                                 acrylamide to be a potential occupational
                                 carcinogen as defined by the OSHA
                                 carcinogen policy [29 CFR 1990].
Current OSHA PEL . . . . . . . . 0.3 mg/m3 TWA [skin]
1989 OSHA PEL. . . . . . . . . . 0.03 mg/m3 TWA [skin]
1993-1994 ACGIH TLV. . . . . . . 0.03 mg/m3 TWA [skin], A2
Description of substance . . . . White crystalline, odorless solid.
LEL. . . . . . . . . . . . . . . Unknown
Original (SCP) IDLH* . . . . . . Unknown  [*Note: "Effective" IDLH = 600
                                 mg/m3  -- see discussion  below.]
Basis for original (SCP) IDLH. . Very little data are available on which to
                                 base an IDLH for acrylamide.  For this draft
                                 technical standard, therefore, respirators
                                 have been selected on the basis of the
                                 assigned protection factor afforded by each
                                 device up to 2,000 x the OSHA PEL of
                                 0.3 mg/m3 (i.e., 600 mg/m3); only the "most
                                 protective" respirators are permitted for use
                                 in concentrations exceeding 600 mg/m3). 
                                 Calculations based on an oral LD50 of 150 to
                                 180 mg/kg for guinea pigs, rabbits, and rats
                                 [McCollister et al. 1964] indicate that a
                                 worker should be able to escape within 30
                                 minutes without injury or irreversible health
                                 effects from 600 mg/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
______________________________________________________________________________
Mammal   Hashimoto 1979   oral   100-200  -----  700-1,400 mg/m3  70-140 mg/m3
Mouse    Hashimoto et al. oral   107      -----        749 mg/m3      75 mg/m3
         1981
Rabbit   McCollister      oral   150      -----      1,050 mg/m3     105 mg/m3
         et al. 1964 
G. pig   McCollister      oral   150      -----      1,050 mg/m3     105 mg/m3
         et al. 1964
Rat      Paulet and       oral   124      -----        868 mg/m3      87 mg/m3
         Vidal 1975

Human data . . . . . . . . . . . None relevant for use in determining the
                                 revised IDLH.

Revised IDLH: 60 mg/m3
Basis for revised IDLH: No inhalation toxicity data are available on which to base an IDLH for acrylamide. Based on acute oral toxicity data in animals [Hashimoto 1979], a value of about 70 mg/m3 would have been appropriate. However, the revised IDLH for acrylamide is 60 mg/m3 based on being 2,000 times the OSHA PEL of 0.03 mg/m3 that was promulgated in 1989 (2,000 is an assigned protection factor for respirators; only the most reliable respirators are recommended above 2,000 times the OSHA PEL). [Note: NIOSH recommends as part of its carcinogen policy that the "most protective" respirators be worn for acrylamide at concentrations above 0.03 mg/m3.]

REFERENCES:

1. Hashimoto K [1979]. Safety of acrylamide monomer. Satisfactory understanding of the toxicity. Kagaku to Seibutsu 17:495-498 (in Japanese).
2. Hashimoto K, Sakamoto J, Tanii H [1981]. Neurotoxicity of acrylamide and related compounds and their effects on male gonads in mice. Arch Toxicol 47:179-189.
3. McCollister DD, Oyen F, Rowe VK [1964]. Toxicology of acrylamide. Toxicol Appl Pharmacol 6(2):172-181.
4. Paulet G, Vidal [1975]. De la toxicite de quelques esters acryliques et methacryliques de l'acrylamide et des polyacrylamides. Arch Mal Prof 36:58-60 (in French).