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Chlorinated diphenyl oxide

May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)

CAS number: 31242–93–0

NIOSH REL: 0.5 mg/m3 TWA

Current OSHA PEL: 0.5 mg/m3 TWA

1989 OSHA PEL: Same as current PEL

1993-1994 ACGIH TLV: 0.5 mg/m3 TWA

Description of Substance: Light-yellow, very viscous, waxy liquid.

LEL: . . Unknown

Original (SCP) IDLH*: Unknown [*Note: “Effective” IDLH = 5 mg/m3 — see discussion below.]

Basis for original (SCP) IDLH: No quantitative data are available concerning the toxic effects produced by the inhalation of chlorinated diphenyl oxide. Therefore, for this draft technical standard, using an analogy with the chloronaphthalenes, the respirators have been selected on the basis of the assigned protection factor afforded by each device up to 10 × the OSHA PEL of 0.5 mg/m3 (i.e., 5 mg/m3); only the “most protective” respirators are permitted for use in concentrations exceeding 5 mg/m3.

Short-term exposure guidelines: None developed


Lethal dose data:

Species Reference Route LD50(mg/kg) LDLo(mg/kg) Adjusted LD Derivedvalue
C12H9ClOG. pig Clayton and Clayton 1981 oral —– 600 4,200 mg/m3 420 mg/m3
C12H8Cl2OG. pig Clayton and Clayton 1981 oral —– 1,000 7,000 mg/m3 700 mg/m3
C12H7Cl3OG. pig Clayton and Clayton 1981 oral —– 1,200 8,400 mg/ m3 840 mg/m3
C12H6Cl4OG. pig Clayton and Clayton 1981 oral —– 50 350 mg/m3 35 mg/m3
C12H5Cl5OG. pig


Clayton and Clayton 1981Hofmann 1957 oraloral ———- 1000.3 700 mg/m32.1 mg/m3 70 mg/m30.2 mg/m3
C12H4Cl6OG. pig Clayton and Clayton 1981 oral —– 50 350 mg/m3 35 mg/m3
C12H3Cl7ORat NAS 1953 oral —– 500 3,500 mg/m3 350 mg/m3
C12H2Cl8ORat NAS 1953 oral —– 500 3,500 mg/m3 350 mg/m3
C12HCl9ORat NAS 1953 oral —– 500 3,500 mg/m3 350 mg/m3


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

Revised IDLH: 5 mg/m3Basis for revised IDLH: No inhalation toxicity data are available on which to base an IDLH for chlorinated diphenyl oxide. Based on acute oral toxicity data in animals [Clayton and Clayton 1981], a value of about 35 mg/m3 would have been appropriate for chlorinated diphenyl oxide. However, the revised IDLH for chlorinated diphenyl oxide is 5 mg/m3 based on being 10 times the NIOSH REL and OSHA PEL of 0.5 mg/m3 (10 is an assigned protection factor for respirators and was used during the Standards Completion Program for deciding when the “most protective” respirators should be used for chlorinated diphenyl oxide).



1. Clayton GD, Clayton FE, eds. [1981]. Patty’s industrial hygiene and toxicology. 3rd rev. ed. Vol. 2A. Toxicology. New York, NY: John Wiley & Sons, Inc., p. 2550.

2. Hofmann HT [1957]. Neuere erfahrungen mit hochtoxischen chlorkohlenwasserstoffen. Arch Exp Pathol Pharmakol 243:228 (in German).

3. NAS [1953]. Relationship between chemical structure and toxic action on rats. National Academy of Sciences, National Research Council, Chemical-Biological Coordination Center, Review 5:16.