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o-Dichlorobenzene
May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 95–50–1
NIOSH REL: 50 ppm (300 mg/m3) CEILING
Current OSHA PEL: 50 ppm (300 mg/m3) CEILING
1989 OSHA PEL: Same as current PEL
1993-1994 ACGIH TLV: 25 ppm (150 mg/m3) TWA, 50 ppm (301 mg/m3) STEL
Description of Substance: Colorless to pale-yellow liquid with a pleasant, aromatic odor.
LEL:. . 2.2% (10% LEL, 2,200 ppm)
Original (SCP) IDLH: 1,000 ppm
Basis for original (SCP) IDLH: The chosen IDLH is based on the statement by ACGIH [1971] that 1,000 ppm was fatal to guinea pigs after 20 hours [Browning 1953]. ACGIH [1971] also reported that Cameron et al. [1937] found liver damage in animals after exposure for a few hours at 50 to 800 ppm.
Short-term exposure guidelines: None developed
ACUTE TOXICITY DATA
Lethal concentration data:
| Species | Reference | LC50(ppm) | LCLo(ppm) | Time | Adjusted 0.5-hrLC (CF) | Derivedvalue |
|---|---|---|---|---|---|---|
| G. pigG. pig
Rat |
Browning 1953Cameron et al. 1937
Hollingsworth et al. 1958 |
———-
—– |
1,000800
821 |
20 hr24 hr
7 hr |
3,450 ppm (3.45)2,880 ppm (3.6)
1,970 ppm (2.4) |
345 ppm288 ppm
197 ppm |
Lethal dose data:
| Species | Reference | Route | LD50(mg/kg) | LDLo(mg/kg) | Adjusted LD | Derived value |
|---|---|---|---|---|---|---|
| RatG. pig
Rabbit Mouse |
Ben-Dyke et al. 1970Patty 1963
Thomson 1976/77 Yakkyoku 1981 |
oraloral
oral oral |
5002,000
500 4,386 |
———-
—– —– |
573 ppm2,291 ppm
573 ppm 5,025 ppm |
57 ppm229 ppm
57 ppm 503 ppm |
Other animal data: RD50 (mouse), 182 ppm [DeCeaurriz et al. 1981].
Human data: Concentrations up to 100 ppm have been reported to have caused sporadic irritation of the eyes and respiratory tract [Elkins 1959].
| Revised IDLH: 200 ppmBasis for revised IDLH: The revised IDLH for o-dichlorobenzene is 200 ppm based on acute inhalation toxicity data in animals [Hollingsworth et al. 1958]. This may be a conservative value due to the lack of relevant acute toxicity data for workers exposed to concentrations above 100 ppm. |
REFERENCES:
1. ACGIH [1971]. o-Dichlorobenzene. In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, p. 76.
2. Ben-Dyke R, Sanderson DM, Noakes DN [1970]. Acute toxicity data for pesticides (1970). World Review of Pesticide Control 9:119-127.
3. Browning E [1953]. Toxicity of industrial organic solvents. New York, NY: Chemical Publishing Company, p. 190.
4. Cameron GR, Thomas JC, Ashmore SA, Buchan JL, Warren EH, Hughes AWM [1937]. The toxicity of certain chlorine derivatives of benzene, with special reference to o-dichlorobenzene. J Pathol Bacteriol 44(2):281-296.
5. DeCeaurriz JC, Micillino JC, Bonnet P, Guenier JP [1981]. Sensory irritation caused by various industrial airborne chemicals. Toxicol Lett 9(2):137-143.
6. Elkins HB [1959]. The chemistry of industrial toxicology. 2nd ed. New York, NY: John Wiley & Sons, Inc., p. 150.
7. Hollingsworth RL, Rowe VK, Oyen F, Torkelson TR, Adams EM [1958]. Toxicity of o-dichlorobenzene. AMA Arch Ind Health 17:180-187.
8. Patty FA, ed. [1963]. Industrial hygiene and toxicology. 2nd rev. ed. Vol. II. Toxicology. New York, NY: Interscience Publishers, Inc., p. 1336.
9. Thomson WT [1976/77]. Agricultural chemicals. Fresno, CA: Thomas Publications, 3:32.
10. Yakkyoku (Pharmacy) [1981]; 32:471-474 (in Japanese).