Mercury (organo) alkyl compounds (as Hg)

CAS number: Varies

NIOSH REL: 0.01 mg/m³ TWA, 0.03 mg/m³ STEL [skin]

Current OSHA PEL: 0.01 mg/m³ TWA, 0.04 mg/m³ CEILING

1989 OSHA PEL: 0.01 mg/m³ TWA, 0.03 mg/m³ STEL [skin]

1993-1994 ACGIH TLV: 0.01 mg/m³ TWA, 0.03 mg/m³ STEL [skin]

Description of substance: Varies

Original (SCP) IDLH: 10 mg Hg/m³

Basis for original (SCP) IDLH: The chosen IDLH is based on the statement by ACGIH [1971] that mice died within 3 to 5 hours at 10 to 30 mg/m³ organic mercury [Trakhtenberg 1950]. The chosen IDLH seems reasonable because NIOSH [1976] cited a mouse intraperitoneal LD_LO for dipropylmercury of 2 mg/kg [NRC 1952]. If the IDLH were estimated from this information, a value of 14 mg/m³ would be obtained.

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
HgC4H10 Rat	Russkykh &Frolova 1973	258 mg/m3	-----	?	?	?
HgC4H10 Mouse	Russkykh &Frolova 1973	91 mg/m3	-----	?	?	?
Hg (organo) alkyl Mouse	Trakhtenberg 1950	-----	10-30 mg/m3	3 hr	18-54 mg Hg/m3 (1.8)	1.8-5.4 mg Hg/m3
Hg (organo) alkyl Mouse	Trakhtenberg 1950	-----	10-30 mg/m3	5 hr	22-26 mg Hg/m3 (2.2)	2.2-2.6 mg Hg/m3

Lethal dose data:

Species	Reference	Route	LD50 (mg/kg)	LDLo (mg/kg)	Adjusted LD	Derived value
HgC4H10 Rat	Izmerov et al. 1982	oral	51	-----	278 mg Hg/m3	28 mg Hg/m3
HgC4H10 Mouse	Izmerov et al. 1982	oral	44	-----	240 mg Hg/m3	24 mg Hg/m3
HgC4H6O4 Rat	Grin et al. 1973	oral	40.9	-----	180 mg Hg/m3	18 mg Hg/m3
HgC4H6O4 Mouse	Grin et al. Grin et al. 1973	oral	23.9	-----	105 mg Hg/m3	11 mg Hg/m3
HgC6H12O6 Rat	Frear 1969	oral	200	-----	742 mg Hg/m3	74 mg Hg/m3
HgC6H14 Mouse	NRC 1952	i.p.	-----	1.9	9.3 mg Hg/m3	0.9 mg Hg/m3

Human data: Deaths have resulted from 3 months exposure to diethyl mercury at an estimated concentration of 1 mg/m³ [Hill 1943]. The lethal dose of methyl mercury is estimated to be 200 mg, with paresthesia of the hands, feet, and mouth occurring at a total body burden of 40 mg [Bakir et al. 1973]. [Note: An oral dose of 200 mg of methyl mercury is equivalent to a worker being exposed to about 125 mg Hg/m³ for 30 minutes, assuming a breathing rate of 50 liters per minute and 100% absorption.]

Revised IDLH: 2 mg Hg/m3 Basis for revised IDLH: The revised IDLH for mercury (organo) alkyl compounds is 2 mg Hg/m3 based on acute toxicity data in humans [Bakir et al. 1973; Hill 1943] and animals [Trakhtenberg 1950].

REFERENCES:

1. ACGIH [1971]. Mercury (alkyl compounds). In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 151-152.

2. Bakir F, Damluji SF, Amin-Zaki L, Murtadha M, Khalidi A, Al-Rawi NY, Tikriti S, Dhahir HI, Clarkson TW, Smith JC, Doherty RA [1973]. Methyl mercury poisoning in Iraq. Science 181:230-241.

3. Frear EH, ed. [1969]. Pesticide index. 4th ed. State College, PA: College Science Publishers, p. 269.

4. Grin NV, Ezmachenko AB, Govozunova NN, Tepukina LA [1973]. Prognosis of the safe concentrations of some soluble compounds of mercury. Gig Sanit 46(8):12-14 (in Russian).

5. Hill WH [1943]. A report of two deaths from exposure to the fumes of a di-ethyl mercury. Can J Public Health 34:158-160.

6. Izmerov NF, Sanotsky IV, Sidorov KK [1982]. Toxicometric parameters of industrial toxic chemicals under single exposure. Moscow, Russia: Centre of International Projects, GKNT, p. 52.

7. NIOSH [1976]. OW3225000. Mercury, dipropyl-. In: Registry of toxic effects of chemical substances, 1976 ed. Cincinnati, OH: 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. 76-191, p. 683.

8. NRC [1952]. Summary tables of biological tests. Washington, DC: National Research Council, Biological Coordination Center, National Academy of Science Library, p. 320.

9. Russkykh VA, Frolova EN [1973]. Materials on substantiation of the maximal permissible concentration of diethylmercury in the air of the working zone. Gig Sanit 38(1):100-102 (in Russian).

10. Trakhtenberg IM [1950]. The toxicity of vapors of organic mercury compounds (ethylmercuric phosphate and ethylmercuric chloride) in acute and chronic intoxication (experimental data). Gig Sanit 6:13-17 (translated).