2-Aminopyridine

May 1994

Immediately Dangerous to Life or Health Concentrations (IDLH)

CAS number: 504-29-0

NIOSH REL: 0.5 ppm (2 mg/m3) TWA

Current OSHA PEL: 0.5 ppm (2 mg/m3) TWA

1989 OSHA PEL: Same as current PEL

1993-1994 ACGIH TLV: 0.5 ppm (1.9 mg/m3) TWA

Description of substanceL: White powder, leaflets, or crystals with a characteristic odor.

LEL: Unknown

Original (SCP) IDLH: 5 ppm

Basis for original (SCP) IDLH: Very little quantitative data are available on which to base an IDLH for 2-aminopyridine. The chosen IDLH is based on the statement by ACGIH [1971] that a 5-hour exposure to about 5 ppm produced headache, increased blood pressure, and nausea in a worker [Watrous and Schulz 1950].

Short-term exposure guidelines: None developed

ACUTE TOXICITY DATA

Lethal dose data:

			LL50	LCLo		Derived
Species	Reference	Route	(mg/kg)	(mg/kg)	Adjusted LD	Value
Rat	Marhold 1986	oral	200	—–	385 ppm	39 ppm
Mouse	Verschueren 1983	oral	50	—–	90 ppm	9 ppm

Human data: A 5-hour exposure to approximately 5 ppm caused severe headache, increased blood pressure, flushing of the extremities, and nausea [Watrous and Schulz 1950]

Revised IDLH: 5 ppm [Unchanged]Basis for revised IDLH: Based on acute inhalation toxicity data in humans [Watrous and Schulz 1950], the original IDLH for 2-aminopyridine (5 ppm) is not being revised at this time. This may be a conservative value due to the lack of relevant acute toxicity data for workers exposed to concentrations above 5 ppm.

References:

ACGIH [1971]. 2-Aminopyridine. In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, p. 11.
Marhold J [1986]. Prehled Prumyslove Toxikologie, Organicke Latky. Prague, Czechoslovakia: Avicenum, p. 838 (in Czechoslovakian).
Verschueren K [1983]. Handbook of environmental data of organic chemicals. 2nd ed. New York, NY: Van Nostrand Reinhold, Co., p. 192.
Watrous RM, Schulz HN [1950]. Cyclohexylamine, p-chlornitrobenzene, 2-aminopyridine: toxic effects in industrial use. Ind Med Surg 19(7):317-320.