Carbaryl

CAS number: 63–25–2

NIOSH REL: 5 mg/m³ TWA

Current OSHA PEL: 5 mg/m³ TWA

1989 OSHA PEL: Same as current PEL

1993-1994 ACGIH TLV: 5 mg/m³ TWA

Description of Substance: White or gray, odorless solid.

LEL: . . Noncombustible Solid

Original (SCP) IDLH: 600 mg/m³

Basis for original (SCP) IDLH: Because no useful data on acute inhalation toxicity are available for carbaryl, the chosen IDLH is based on the rat oral LD₅₀ of 89 mg/kg [Boyd and Taylor 1971 cited by NIOSH 1974]. In addition, ACGIH [1971] reported that female rats may occasionally be killed by a single oral dose of 100 mg/kg [Gaines 1969].

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
Rabbit G. pig Dog Rat Rat Cat Mouse Rat	AAPCO 1966 Benson and Dorough 1984 Buck 1979 Gaines 1960 Gaines 1960 Gig Sanit 1967 Stevens et al. 1972 Weiss and Orzel 1967	oral oral oral oral oral oral oral oral	710 250 759 850 500 150 128 230	----- ----- ----- ----- ----- ----- ----- -----	4,970 mg/m3 1,750 mg/m3 5,313 mg/m3 5,950 mg/m3 3,500 mg/m3 1,050 mg/m3 896 mg/m3 1,610 mg/m3	497 mg/m3 175 mg/m3 531 mg/m3 595 mg/m3 350 mg/m3 105 mg/m3 90 mg/m3 161 mg/m3

Other animal data: A concentration of about 75 mg/m³ produced typical poisoning in dogs within 5 hours [Carpenter et al. 1961].

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

Revised IDLH: 100 mg/m3 Basis for revised IDLH: The revised IDLH for carbaryl is 100 mg/m3 based on acute toxicity data in animals [Carpenter et al. 1961; Gig Sanit 1967; Stevens et al. 1972].

REFERENCES:

1. AAPCO [1966]. Pesticide chemicals official compendium. Topeka, KS: Association of American Pesticide Control Officials, Inc., p. 192.

2. ACGIH [1971]. Carbaryl (Sevin). In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 37-38.

3. Benson WH, Dorough HW [1984]. Comparative ester hydrolysis of carbaryl and ethiofencarb in four mammalian species. Pest Biochem Physiol 21:199-206.

4. Boyd EM, Taylor FI [1971]. Toxaphene toxicity in protein-deficient rats. Toxicol Appl Pharmacol 18:158-167.

5. Buck WB [1979]. Clinical toxicosis induced by insecticides. Vet Med Small Anim Clin 74:1119.

6. Carpenter CP, Weil CS, Palm PE, Woodside MW, Nair JH III, Smyth HF Jr [1961]. Mammalian toxicity of 1-naphthyl-N-methylcarbamate (Sevin insecticide). J Agri Food Chem 9(1):30-39.

7. Gaines TB [1960]. The acute toxicity of pesticides to rats. Toxicol Appl Pharmacol 2:88-99.

8. Gaines TB [1969]. Acute toxicity of pesticides. Toxicol Appl Pharmacol 14:515-534.

9. Gig Sanit [1967]; 32(4):29-33 (in Russian).

10. NIOSH [1974]. FC59500. Carbamic acid, methyl-, 1-naphthyl ester. In: The toxic substances list, 1974 ed. Rockville, MD: U.S. Department of Health, Education, and Welfare, Public Health Service, Center for Disease Control, National Institute for Occupational Safety and Health, DHEW (NIOSH) Publication No. 74-134, p. 182.

11. Stevens JT, Stitzel RE, McPhillips JJ [1972]. Effects of anticholinesterase insecticides on hepatic microsomal metabolism. J Pharmacol Exp Ther 181:576-583.

12. Weiss LH, Orzel RA [1967]. Some comparative toxicologic and pharmacologic effects of dimethyl sulfoxide as a pesticide solvent. Toxicol Appl Pharmacol 11:546-557.