Thallium (soluble compounds, as Tl)

CAS number: Varies

NIOSH REL: 0.1 mg/m3 TWA [skin]

Current OSHA PEL: 0.1 mg/m3 TWA [skin]

1989 OSHA PEL: Same as current PEL

1993­1994 ACGIH TLV: 0.1 mg/m3 TWA [skin]

Description of substance: Varies

Original (SCP) IDLH*: 20 mg TI/m3

Basis for original (SCP) IDLH: Because no data on acute inhalation toxicity are available on which to base the IDLH for the soluble compounds of thallium, research in this area is needed. The chosen IDLH has been estimated from the data given by; ACGIH [1971] that LD₅₀ values for different thallium compounds, by various routes of administration and for several species of animals ranged from 3 to 92 mg/kg [Downs et al. 1960 as cited by Patty 1963]. Further support for the chosen IDLH can be gained from the statement by Deichmann and Gerarde [1969] that a dose of 0.2 gram (inorganic salts of thallium) may be lethal unless treatment if started promptly.

ShortShort­term exposure guidelines: None developed

ACUTE TOXICITY DATA:

Lethal dose data:

Species	Reference	Route	LD50 <ALIGN="CENTER"(mg/kg)	LDLo <ALIGN="CENTER"(mg/kg)	Adjusted LD	Derived value
TlCl Mouse	Tikhova 1964	oral	24	-----	143 mg Tl/m3	14 mg Tl/m3
TlSO4 Rat Mouse	Gekkan Yakuji 1980 Tikhova 1964	oral oral	16 23.5	----- -----	91 mg Tl/m3 133 mg Tl/m3	9.1 mg Tl/m3 13 mg Tl/m3
TlC2H3O2 Mouse Rat	Kusano 1969 Venugopal and Luckey 1978	oral oral	35 41.3	----- -----	191 mg Tl/m3 225 mg Tl/m3	19 mg Tl/m3 23 mg Tl/m3
Tl2CO3 Mouse Rat	Tikhova 1964 Tikhova 1964	oral oral	21 -----	----- 23	128 mg Tl/m3 140 mg Tl/m3	13 mg Tl/m3 14 mg Tl/m3

Human data : Lethal oral doses ranging from 0.9 to 9.4 mg/kg have been reported [Gekkan Yakuji 1980; Tanaka et al. 1978; Venugopal and Luckey 1978; Yakkyoku 1977]. [Note: an oral dose ranging from 0.9 to 9.4 mg/kg is equivalent to a 70-kg worker being exposed to concentrations ranging from about 40 to 450 mg/m³ for 30 minutes, assuming a breathing rate of 50 liters per minute and 100% absorption.]

Revised IDLH: 15 mg Tl/m3 Basis for revised IDLH: No inhalation toxicity data are available on which to base an IDLH for soluble thallium compounds. Therefore, the revised IDLH for soluble thallium compounds is 15 mg Tl/ m3 based on acute oral toxicity data in humans [Gekkan Yakuji 1980; Tanaka et al. 1978; Venugopal and Luckey 1978; Yakkyoku 1977] and animals [Kusano 1969; Tikhova 1964].

REFERENCES:

1. ACGIH [1971]. Thallium. In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, p. 256.

2. Deichmann WB, Gerarde HW [1969]. Thallium. In; Toxicology of drugs and chemicals. New York, NY: Academic Press, Inc., pp. 582-583.

3. Downs WL, Scott JK, Steadman LT, Maynard EA [1960]. Acute and sub-acute toxicity studies of thallium compounds. Am Ind Hyg Assoc J 21:399-406.

4. Gekkan Yakuji (Pharmaceuticals Monthly) [1980]; 22:291-298 (in Japanese).

5. Kusano T [1969]. Studies on the improved effectiveness of anticoagulative rodenticides on rodents. I. Synergistic toxic action between coumarin or indandione derivatives and thallium salts on mice. Journal of the Faculty of Agriculture, Tottori University 5(2):15-52.

6. Patty FA, ed. [1963]. Industrial hygiene and toxicology. 2nd rev. ed. Vol. ll. Toxicology. New York, NY: Interscience Publishers, Inc., p. 1140.

7. Tanaka J. Yonezawa T. Ueyama M [1978]. Acute thallotoxicosis: neuropathological and spectrophotometric studies on an autopsy case. J Toxicol Sci 3:325-334.

8. Tikhova TS [1964]. Problems of labor hygiene in the production of metallic thallium and its salts. Gig Sanit 29(2):26-32 (translated).

9. Venugopal B. Luckey TD [1978]. Metal toxicity in mammals. Vol. 2. Chemical toxicity of metals and metalloids. New York, NY: Plenum Press, p. 101.

10. Yakkyoku (Pharmacy) [1977]; 28:329 (in Japanese).