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Oxalic acid
May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 144–62–7
NIOSH REL: 1 mg/m3 TWA, 2 mg/m3 STEL
Current OSHA PEL: 1 mg/m3 TWA
1989 OSHA PEL: 1 mg/m3 TWA, 2 mg/m3 STEL
1993-1994 ACGIH TLV: 1 mg/m3 TWA, 2 mg/m3 STEL
Description of substance: Colorless, odorless powder or granular solid.
LEL: . Unknown
Original (SCP) IDLH: 500 mg/m3
Basis for original (SCP) IDLH: The chosen IDLH has been calculated from the total oral lethal dose for man of 5 grams [ACGIH 1971].
Short-term exposure guidelines: None developed
ACUTE TOXICITY DATA:
Lethal dose data:
| Species | Reference | Route | LD50(mg/kg) | LDLo(mg/kg) | Adjusted LD | Derived value |
|---|---|---|---|---|---|---|
| Dog | Flury & Zernik 1935 | oral | —– | 1,000 | 7,000 mg/m3 | 700 mg/m3 |
| Rat | Shtabsky & Shatinskaya 1985 | ? | —– | 1,400 | 9,800 mg/m3 | 980 mg/m3 |
| Rat | Vernot et al. 1977 | oral | —– | 7,500 | 52,500 mg/m3 | 5,250 mg/m3 |
Human data: It has been reported that the lethal oral dose is 15 to 30 grams [Webster 1930]. [Note: An oral dose of 15 to 30 grams is equivalent to a 30-minute exposure to 10,000 to 20,000 mg/m3 assuming a 50 liter per minute breathing rate and 100% absorption.]
| Revised IDLH: 500 mg/m3 [Unchanged]Basis for revised IDLH: No inhalation toxicity data are available on which to base an IDLH for oxalic acid. Therefore, based on acute oral toxicity data in humans [Webster 1930] and animals [Flury and Zernik 1935], the original IDLH for oxalic acid (500 mg/m3) is not being revised at this time. |
REFERENCES:
1. ACGIH [1971]. Oxalic acid. In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, p. 193.
2. Flury F, Zernik F [1935]. Zusammenstellung der toxischen und letalen dosen für die gebräuchlichsten gifte und versuchstiere. Abder Hand Biol Arbeitsmethod 4:1289-1422 (in German).
3. Shtabsky BM, Shatinskaya EG [1985]. Evaluation of cumulative properties of toxic chemicals from the subchronic experiment. Gig Sanit 50(3):57-60 (in Russian).
4. Vernot EH, MacEwen JD, Haun CC, Kinkead FR [1977]. Acute toxicity and skin corrosion data for some organic and inorganic compounds and aqueous solutions. Toxicol Appl Pharmacol 42:417-423.
5. Webster RW [1930]. Legal medicine and toxicology. Philadelphia, PA: W.B. Saunders.