Copper (dusts and mists, as Cu)

CAS number: 7440–50–8 (Metal)

NIOSH REL: 1 mg/m³ TWA

1989 OSHA PEL: Same as current PEL

Current OSHA PEL: 1 mg/m³ TWA

1993-1994 ACGIH TLV: 1 mg/m³ TWA

Description of Substance: Varies

Original (SCP) IDLH*: No Evidence [*Note: “Effective” IDLH = 2,000 mg Cu/m³ — see discussion below.]

Basis for original (SCP) IDLH: There is no evidence that an acute exposure to a high concentration of copper dusts and mists could impede escape within 30 minutes. Browning [1969] noted that there is little evidence that copper presents a serious industrial hazard, either from acute or chronic poisoning. For this draft technical standard, therefore, respirators have been selected on the basis of the assigned protection factor afforded by each device up to 2,000 × the OSHA PEL of 1 mg Cu/m³ (i.e., 2,000 mg Cu/m³); only the “most protective” respirators are permitted for use in concentrations exceeding 2,000 mg Cu/m³.

Short-term exposure guidelines: None developed

ACUTE TOXICITY DATA

Lethal concentration data:

Species	Reference	LC50	LCLo	Time	Adjusted 0.5-hr LC (CF)	Derived value
Cu(OH)2 Mammal	Worthing 1991	>2,000 mg/m3	-----	?	?	?

Lethal dose data:

Species	Reference	Route	LD50 (mg/kg)	LDLo (mg/kg)	Adjusted LD	Derived value
Cu(OH)2 Rat	Sine 1991	oral	1,000	-----	4,559 mg Cu/m3	456 mg Cu/m3
CuCl Rat	Coulston and Korte 1975	oral	140	-----	629 mg Cu/m3	63 mg Cu/m3
CuC4H6O4 Rat	Marhold 1977	oral	595	-----	1,457 mg Cu/m3	146 mg Cu/m3
CuSO4 Rat	Siegle and Sisler 1977	oral	300	-----	836 mg Cu/m3	84 mg Cu/m3

Human data: It has been stated that there is little evidence that copper presents a serious industrial hazard, either from acute or chronic poisoning [Browning 1969]. Inhalation of copper salts can result in irritation of the nasal mucous membranes [Clayton and Clayton 1981]. A lethal oral dose of 857 mg of CuSO₄/kg (equivalent to 341 mg Cu/kg) has been reported [Csiky 1958]. [Note: An oral dose of 341 mg Cu/kg is equivalent to a 70-kg worker being exposed to 227 mg Cu/m³ for 30 minutes, assuming a breathing rate of 50 liters per minute and 100% absorption.]

Revised IDLH: 100 mg Cu/m3 Basis for revised IDLH: The revised IDLH for copper dusts and mists is 100 mg Cu/m3 based on acute oral toxicity data in humans [Csiky 1958] and animals [Coulston and Korte 1975; Marhold 1977; Siegel and Sisler 1977]. This may be a conservative value due to the lack of relevant acute inhalation toxicity data in workers.

 

REFERENCES:

1. Browning E [1969]. Toxicity of industrial metals. 2nd ed. New York, NY: Appleton-Century-Crofts, p. 148.

2. Clayton GD, Clayton FE, eds. [1981]. Patty’s industrial hygiene and toxicology. 3rd rev. ed. Vol. 2A. Toxicology. New York, NY: John Wiley & Sons, Inc., pp. 1620-1630.

3. Coulston F, Korte F, eds. [1975]. Heavy metal toxicity, safety and hormology. In: Environmental Quality & Safety, Supplement 1. New York, NY: Georg Thieme Publishers, pp. 1-120.

4. Csiky P [1958]. Uber die akuten kupfersulfat-vergiftungen. Arch Toxikol 17:20-26 (in German).

5. Marhold JV [1977]. Personal communication. VUOS, 539-18, Pardubice, Czechoslovakia, March 29, 1977.

6. Siegel MR, Sisler HD [1977]. Antifungal compounds. Vol. 1. New York, NY: Marcel Dekker, p. 507.

7. Sine C, ed. [1991]. Copper hydroxide. In: Farm chemicals handbook ’91, p. C89.

8. Worthing CR, ed. [1991]. Copper hydroxide. In: The pesticide manual. A world compendium. 9th ed. Farnham, Surrey, United Kingdom: The British Crop Protection Council, p. 184.