Propylene dichloride

CAS number: 78–87–5

NIOSH REL: None established; NIOSH considers propylene dichloride to be a potential occupational carcinogen as defined by the OSHA carcinogen policy [29 CFR 1990].

Current OSHA PEL: 75 ppm (350 mg/m³) TWA

1989 OSHA PEL: 75 ppm (350 mg/m³) TWA, 110 ppm (510 mg/m³) STEL

1993-1994 ACGIH TLV: 75 ppm (347 mg/m³) TWA, 110 ppm (508 mg/m³) STEL

Description of substance: Colorless liquid with a chloroform-like odor.

LEL :. . 3.4% (10% LEL, 3,400 ppm)

Original (SCP) IDLH: 2,000 ppm

Basis for original (SCP) IDLH: The chosen IDLH is based on the rat 4-hour LC₅₀ of 2,000 ppm [Carpenter et al. 1949 cited by Spector 1956].

Short-term exposure guidelines: None developed

ACUTE TOXICITY DATA:

Lethal concentration data:

Species	Reference	LC50 (ppm)	LCLo (ppm)	Time	Adjusted 0.5-hr LC (CF)	Derived value
Rat Mouse Rat	Carpenter et al. 1949 Clayton & Clayton 1981 Pozzani et al. 1959	2,000 720 2,980	----- ----- -----	4 hr 10 hr 8 hr	4,000 ppm (2.0) 1,944 ppm (2.7) 7,450 ppm (2.5)	400 ppm 194 ppm 745 ppm

Lethal dose data:

Species	Reference	Route	LD50 (mg/kg)	LDLo (mg/kg)	Adjusted LD	Derived value
Mouse Rat G. pig	Marhold 1986 Pozzani et al. 1959 Sine 1993	oral oral oral	860 1,947 2,000	----- ----- -----	1,281 ppm 2,900 ppm 3,111 ppm	128 ppm 290 ppm 311 ppm

Other animal data: Animals exposed to 400 ppm for 7 hours per day, 5 days per week for 128 to 140 exposures had no histologic changes [Heppel et al. 1948].

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

Revised IDLH: 400 ppm Basis for revised IDLH: The revised IDLH for propylene dichloride is 400 ppm based on inhalation toxicity data in animals [Carpenter et al. 1949; Heppel et al. 1948]. [Note: NIOSH recommends as part of its carcinogen policy that the "most protective" respirators be worn for propylene dichloride at any detectable concentration.]

REFERENCES:

1. Carpenter CP, Smyth HF Jr, Pozzani UC [1949]. The assay of acute vapor toxicity, and the grading and interpretation of results on 96 chemical compounds. J Ind Hyg Toxicol 31(6):343-346.

2. Clayton GD, Clayton FE, eds. [1981]. Patty's industrial hygiene and toxicology. 3rd rev. ed. Vol. 2B. Toxicology. New York, NY: John Wiley & Sons, Inc., pp. 3529-3532.

3. Heppel LA, Highman B, Peake EG [1948]. Toxicology of 1,2-dichloropropane (propylene dichloride). IV. Effects of repeated exposures to a low concentration of the vapor. J Ind Hyg Toxicol 30:189-191.

4. Marhold J [1986]. Prehled Prumyslove Toxikologie, Organicke Latky. Prague, Czechoslovakia: Avicenum, p. 98 (in Czechoslovakian).

5. Pozzani UC, Weil CS, Carpenter CP [1959]. The toxicological basis of threshold limit values: 5. The experimental inhalation of vapor mixtures by rats, with notes upon the relationship between single dose oral data. Am Ind Hyg Assoc J 20:364-369.

6. Sine C, ed. [1993]. Propylene dichloride. In: Farm chemicals handbook '93, p. C284.

7. Spector WS, ed. [1956]. Handbook of toxicology. Vol. I. Acute toxicities. Philadelphia, PA: W.B. Saunders Company, pp. 332-333.