Phosphorus trichloride
May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 7719–12–2
NIOSH REL: 0.2 ppm (1.5 mg/m3) TWA, 0.5 ppm (3 mg/m3) STEL
Current OSHA PEL: 0.5 ppm (3 mg/m3) TWA
1989 OSHA PEL: 0.2 ppm (1.5 mg/m3) TWA, 0.5 ppm (3 mg/m3) STEL
1993-1994 ACGIH TLV: 0.2 ppm (1.1 mg/m3) TWA, 0.5 ppm (2.8 mg/m3) STEL
Description of substance: Colorless to yellow, fuming liquid with an odor like hydrochloric acid.
LEL :. . Noncombustible Liquid
Original (SCP) IDLH: 50 ppm
Basis for original (SCP) IDLH: The chosen IDLH is based on the statement by ACGIH [1971] that serious disturbances in animals resulted from exposure to 50 to 90 ppm for 1 hour [Butjagin 1904].
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 G. pig |
Weeks et al. 1964 Weeks et al. 1964 |
104 50 |
----- ----- |
4 hr 4 hr |
208 ppm (2.0) 100 ppm (2.0) |
21 ppm 10 ppm |
Lethal dose data:
| Species | Reference | Route | LD50 (mg/kg) | LDLo (mg/kg) | Adjusted LD | Derived value |
| Rat | Parent 1990 | oral | 18 | ----- | 22 ppm | 2.2 ppm |
Other animal data: Cats and guinea pigs exposed for 6 hours at 0.7 ppm showed only mild signs of intoxication and a 1-hour exposure at 2 to 4 ppm failed to produce severe signs of poisoning; however, a single 1-hour exposure at 50 to 90 ppm resulted in serious disturbances [Butjagin 1904].
Human data: Workers exposed to concentrations ranging from 1.8 to 27 ppm had symptoms that included burning of the eyes and throat, irritation of the pharyngeal mucous membranes, and mild bronchitis within 2 to 6 hours after exposure [Sassi 1952].
| Revised IDLH: 25 ppm Basis for revised IDLH: The revised IDLH for phosphorus trichloride is 25 ppm based on acute inhalation toxicity data in humans [Sassi 1952] and animals [Butjagin 1904; Weeks et al. 1964]. |
REFERENCES:
1. ACGIH [1971]. Phosphorus trichloride. In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 211-212.
2. Butjagin PW [1904]. Experimental studies on the effect of technically and hygienically important gases on the organism. Part XII. Studies on phosphorus trichloride. Arch Hyg 49:307-335 (in German). [From ACGIH [1971]. Phosphorus trichloride. In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 211-212.]
3. Parent RA, ed. [1990]. Acute toxicity data. J Am Coll Toxicol, Part B 1:71.
4. Sassi C [1952]. Occupational poisoning with phosphorus trichloride. Med Lav 43:298-306 (in Italian).
5. Weeks MH, Musselman NP, Yevich PP, Jacobson KH, Oberst FW [1964]. Acute vapor toxicity of phosphorus oxychloride phosphorus trichloride and methyl phosphoric dichloride. Am Ind Hyg Assoc J 25:470-475.