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Hexachloronaphthalene
May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 1335–87–1
NIOSH REL: 0.2 mg/m3 TWA [skin]
Current OSHA PEL: 0.2 mg/m3 TWA [skin]
1989 OSHA PEL: Same as current PEL
1993-1994 ACGIH TLV: 0.2 mg/m3 TWA [skin]
Description of Substance: White to light-yellow solid with an aromatic odor.
LEL:. . Noncombustible Solid
Original (SCP) IDLH: 2 mg/m3
Basis for original (SCP) IDLH: Although AIHA [1966] stated that “IDLHs for the chloronaphthalenes are probably unattainable,” an IDLH of 2 mg/m3 for hexachloronaphthalene has been chosen for this draft technical standard. The chosen IDLH is based on the industrial exposure cited by ACGIH [1971] in which fatal cases of hepatic injury occurred in a plant where air concentrations of mixed pentachloronaphthalenes and hexachloronaphthalenes ranged from 1 to 2 mg/m3 [Elkins 1959].
Short-term exposure guidelines: None developed
ACUTE TOXICITY DATA
Animal data: Repeated exposure of rats to 8.9 mg/m3 of a mixture of hexachloronaphthalene and pentachloronaphthalene for up to 4.5 months produced jaundice and was fatal; minor liver injury still occurred at 1.16 mg/m3 [Drinker et al. 1937]. Hexachloronaphthalene has been shown to be more toxic than pentachloronaphthalene in ingestion studies with calves [Bell 1958]. Total doses of hexachloronaphthalene ranging from 5 to 23 mg/kg were given orally in mineral oil over 10 days and lacrimation, salivation, nasal discharge, depression, and anorexia occurred by the 5th day [Bell 1958].
Human data: It has been reported that fatal cases of hepatic injury have occurred from chronic exposures in a plant where air concentrations of mixed pentachloronaphthalenes and hexachloronaphthalenes ranged from 1 to 2 mg/m3 [Elkins 1959].
| Revised IDLH: 2 mg/m3 [Unchanged]Basis for revised IDLH: Based on chronic inhalation toxicity data in humans [Elkins 1959] and animals [Bell 1958, Drinker 1937], the original IDLH for hexachloronaphthalene (2 mg/m3) is not being revised at this time. |
REFERENCES:
1. ACGIH [1971]. Hexachloronaphthalene. In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, p. 125.
2. AIHA [1966]. Chloronaphthalenes. In: Hygienic guide series. Am Ind Hyg Assoc J 27:89.
3. Bell WB [1958]. The relative toxicity of the chlorinated naphthalenes in experimentally produced bovine hyperkeratosis (x-disease). Vet Med 48:135-140.
4. Drinker CK, Warren MF, Bennett GA [1937]. The problem of possible systemic effects from certain chlorinated hydrocarbons. J Ind Hyg Toxicol 19(7):283-299.
5. Elkins HB [1959]. The chemistry of industrial toxicology. 2nd ed. New York, NY: John B. Wiley & Sons, Inc., pp. 151-152.