## Technical Review of Hydrogen Sulfide: Chemistry, Environmental Fate and Ecological Toxicity CAS Registry Number 7783
- 06
- 4
Office of Environmental Information Office of Information Access and Analysis Environmental Analysis Division Analytical Support Branch

October 5 , 2009i 

### Purpose of this Hazard Assessment for Hydrogen Sulfide

This technical report provides an assessment and review of the potential environmental hazards of hydrogen sulfide. Information provided includes a revi ew of available literature concerning ecological toxicity along with a brief review of the chemistry and environmental fate of the chemical. The document assesses the scientific soundness of the readily available data/studies including an assessment of th e dose or concentration levels at which adverse effect(s) were observed.ii 

## T ABLE OF 

## C ONTENTS



### 1. CHEMISTRY AND ENVIRONMENTAL FATE ................................ ............................... 1
1.1. SUMMARY ................................ ................................ ................................ ................................ ................................ ... 1
1.2. SYNONYMS/IDENTI FIERS ................................ ................................ ................................ ................................ ..... 3
1.3. PHYSICAL AND CH EMICAL PROPERTIES ................................ ................................ ................................ ..... 3
1.4. PRODUCTION METH ODS ................................ ................................ ................................ ................................ ...... 4
1.5. USE PROPERTIES ................................ ................................ ................................ ................................ ..................... 5
1.6. ENVIRONMENTAL F ATE ................................ ................................ ................................ ................................ ....... 6
1.7. REFERENCES ................................ ................................ ................................ ................................ ........................... 12


### 2. ECOLOGICAL HAZARD ASSESSMENT ................................ ................................ ....... 15
2.1. SUMMARY ................................ ................................ ................................ ................................ ................................ . 15
2.2. ECOLOGICAL TOXICITY ................................ ................................ ................................ ................................ .... 16
2.3. REFERENCES ................................ ................................ ................................ ................................ ........................... 241 

### 1. CHEMISTRY AND ENVIRONMENTAL FATE



### H S H
1.1. SUMMARY
Hydrogen sulfide (CAS Registry No. 7783

- 06

- 4) is a colorless, flammable gas at room temperature that has an odor of rotten eggs (O'Neil et al., 2006; Lewis, 2001). The molecular formula is H 2 

### S and the molecular weight is 34.08. Hydrogen sulfide is des cribed as soluble over a wide range of temperatures and pressure (Carroll and Mather 1989)). It is soluble in certain polar organic solvents (e.g., methanol, acetone, glycols, and glycol ethers), less soluble in non

polar solvents (e.g., hexane, benzene), and very soluble in alkanolamines (Weil et al., 2006). Hydrogen sulfide is a component of the natural sulfur cycle. It is produced by natural bacterial processes in the environment and is found naturally in crude oil, natural gas, sulfur springs, and vo lcanic gas (Beauchamp et al., 1984; Boon, 1992; Weil et al., 2006). Most of the hydrogen sulfide used commercially is recovered from petroleum, natural gas, and manufactured gas; however, hydrogen sulfide is also manufactured via reactions involving other industrial chemicals such as sulfur and hydrogen gas (Pouliquen et al. 2005). Hydrogen sulfide is also produced as an incidental degradation product by the biological wastewater treatment industry, the agricultural food industry, slaughterhouses and the paper industry (Ulmann’s, 1989). Some important uses of hydrogen sulfide include the manufacture of elemental sulfur, metal sulfides, and thioorganic compounds, and the purification of metal ore. According to industrial reports provided to the U.S. En vironmental Protection Agency (U.S. EPA) under the Inventory Update Rule (U.S. EPA, 2007a), the production volume of hydrogen sulfide in the United States declined from greater than 1 billion pounds per year in 1986 to between 100 and 500 million pounds in 1998 and then returned to greater than 1 billion pounds in 2002. More recent production volume data are not available.2 

### An estimated 100

- 324 million tons of hydrogen sulfide are naturally released to the global atmosphere each year (Pouliquen et al., 2 005). Releases from ocean waters are believed to account for half of this volume, with the remainder originating from volcanoes, flooded ground, and hydrogeological sources such as thermal springs (Pouliquen et al., 2005). Although hydrogen sulfide is on the current Toxics Release Inventory (TRI) toxic chemical list, releases for this chemical are not currently reportable (U.S. EPA, 2007b). Anthropogenic releases of hydrogen sulfide have been estimated to account for less than 5% of total atmospheric hyd rogen sulfide emissions (Beauchamp et al., 1984). Since hydrogen sulfide is a gas at environmental temperatures, it is expected to volatilize from water and soil surfaces. Hydrogen sulfide has also been shown to sorb to soil surfaces resulting in attenua tion in its transfer rate to the atmosphere (Smith et al., 1973). The volatilization rate of hydrogen sulfide in the environment is also influenced by pH. Under basic conditions, hydrogen sulfide dissociates to form bisulfide, a substance that does not v olatilize. Hydrogen sulfide released to the atmosphere is expected to undergo indirect photooxidation with hydroxyl radicals. The predicte d lifetime based on thi s reaction is 0.23

- 2.3 days (Cox, 1975). This substance also undergoes oxidation by reaction with atmospheric oxygen (O 2 

### ) and ozone (Hill, 1973). Measured rates for these processes are not available; however, half

lives are expected to be less than 1 day (Hill, 1973). Hydrogen sulfide is expected to undergo oxidation in soil and water through bo th abiotic and biological processes (Millero et al., 1987; Jorgensen, 1982; WHO, 1981; Hill, 1973). The chemistry and environmental fate of hydrogen sulfide are discussed in this chapter. Synonym and physical

- chemical property information was obtained during a search of the on

line source ChemIDplus, handbook references, the Syracuse Research Corporation (SRC) PHYSPROP database, and the SRC Environmental Fate Data Base. Manufacturing and use information was obtained from Ullmann's encyclopedia articles on hydrogen sulfide.3 

### Environmental fate data were obtained through a search of the literature compiled in SRC's Environmental Fate Data Base, the Hazardous Substances Data Bank (HSDB) record for hydrogen sulfide, the Agency for Toxic Substances and Disea se Registry (ATSDR) toxicological profile for hydrogen sulfide, and estimations performed using the EPI Suite v4.0 software.

1.2. SYNONYMS/IDENTI FIERS (CAS 2007; ChemIDplus, 2008): Dihydrogen monosulfide Dihydrogen sulfide Hydrosulfuric acid Stink damp Sulfur dihydride Sulfur hydride Sulfureted hydrogen

1.3. PHYSICAL AND CH EMICAL PROPERTIES Table 1

- 1 provides selected physical and chemical properties for hydrogen sulfide.4 

### Table 1

- 1. Physical and Chemical Properties of Hydrogen Sulfide (CAS Reg. No. 7 783

- 06

- 4)
Property Value a Conditions Reference Molecular formula H 2 S O'Neil et al., 2006 Molecular weight 34.08 O'Neil et al., 2006 Melting point (°C)

- 85.49 O'Neil et al., 2006 Boiling point (°C)

- 60.33 O'Neil et al., 2006 Water solubility (mg/L ) b,c 3787 2821 2329 20 °C 30 °C 40 °C Carroll and Mather 1989

Log K ow NA Henry’s Law constant (atm

m 3 /mol) 8.4 × 10 - 3 1.08 × 10 - 2 1.3 × 10 - 2 20 °C; pH 7.1 30 °C; pH 7.1 40 °C; pH 7.1 Al

- Haddad et al., 1989; Carroll and Mather 1989
Air

- water partition coeffi cient (K aw ) 0.35 0.43 0.51 20 °C 30 °C 40 °C Calculated from the Henry’s Law constant using data from Carroll and Mather 1989 Hydroxyl radical reaction rate constant (cm 3 /molec

- sec) 4.8 × 10 - 12 Cox, 1975 pKa 7.04 O'Neil et al., 2006 Density (g/L) 1.393 Lide, 2005 Density in air (air = 1) 1.19 O'Neil et al., 2006 Autoignition temperature (°C) 290 Pouliquen et al., 2005 Explosive limits (by volume) Lower limit: 4.3% Upper limit: 46% O'Neil et al., 2006 Odor threshold (ppm) Water: 0.000029 Air: 0.00 05

- 0.3 ATSDR, 2006
Air conversion factors 1 ppm = 1.40 mg/m 3 ATSDR, 2006

a Values are experimental unless otherwise indicated. b The solubility of hydrogen sulfide in water is calculated from the strict Henry’s Law constant over a wide temperature and pressure range (Carroll and Mather 1989): m H2S H = y H2S P, where y H2S is the mol fraction of hydrogen sulfide in the vapor phase, P is the total pressure, and m H2S is the mol fraction of hydrogen sulfide in solution. Multiplying y H2S by P yields the parti al pressure of hydrogen sulfide above the solution.
c These solubilities were originally reported as mol percent in Carroll and Mather (1989) and were converted to mg/L for this table. 

### 1.4. PRODUCTION METH ODS Most of the hydrogen sulfide used commerc ially is obtained through recovery from petroleum, natural gas, or manufactured gas (Beauchamp et al., 1984). In a process called hydrodesulfurization, sulfur

- rich gas

- oil and coke distillate fractions are passed through a fixed

bed catalyst in the presen ce of hydrogen to convert the sulfur compounds into hydrogen sulfide (Beauchamp et al., 1984). Hydrogen sulfide is also produced through hydrogen reduction or acid decomposition of sulfides such as FeS 2 

### or CuS (Pouliquen et al., 2005). An older commercia l5 

### production method involves the direct reaction of sulfur with hydrogen gas or with a hydrocarbon (Weil et al., 2006; Pouliquen et al., 2005; Beauchamp et al., 1984). For example, methane is reacted with sulfur to form a mixture of hydrogen sulfide and c arbon disulfide (Pouliquen et al., 2005). The carbon disulfide can then be hydrolyzed to give additional hydrogen sulfide (Pouliquen et al., 2005). Hydrogen sulfide is formed through bacterial reduction of naturally occurring or anthropogenic sulfate and bacterial decomposition of sulfur

- containing proteins, and it is a principal component of the natural sulfur cycle (Weil et al., 2006; Boon, 1992; WHO, 1981). It is generated as a degradation product by the biological wastewater treatment industry, agric ultural food industry, slaughterhouses and the paper industry (Ulmann’s, 1989). Hydrogen sulfide is present in crude oil, natural gas, sulfur springs, and volcanic gas (Beauchamp et al., 1984). It is released to the environment via water discharge during oil and gas extraction activities (EPA, 1993). The concentration of undissociated hydrogen sulfide in an environmental water sample can be calculated from the dissolved sulfide concentration measured in the sample and the pH, salinity, and temperature o f the solution (APHA 1998).

1.5. USE PROPERTIES Hydrogen sulfide is used in the production of elemental sulfur and sulfuric acid, in the production of inorganic sulfides, thiophenes, organic mercaptans, thioaldehydes, and thioketones, in the metallurg ical industry for the purification of ore through selective flotation, in the manufacture of heavy water for the nuclear industry, and as a reagent in analytical chemistry (HSDB, 2007; O'Neil et al., 2006; Weil et al., 2006; Pouliquen et al., 2005; Lewis, 2001; Beauchamp et al., 1984).6 

### 1.6. ENVIRONMENTAL F ATE 1.6.1. Environmental Transport. Since hydrogen sulfide is a gas, it is expected to partition to the atmosphere; however, atmospheric hydrogen sulfide may dissolve in water that it contacts and sorb onto soil and plant surfaces (ATSDR, 2006)

. 

### Along with sorption to soils, the natural diffusion of hydrogen sulfide from areas of greater concentration to areas of lower concentration will also influence the amount of hydrogen sulfid e found in soil compartments. Measured Henry's Law constants of 8.4 × 10 - 3 

### , 1.08 × 10 - 2 

### , and 1.3 × 10 - 2 

### atm

- m 3 

### /mol at 20, 30, and 40 °C, respectively (pH 7.1), and the corresponding air

- water partition coefficients shown in Table 1

- 1 indicate that increasing te mperature increases the rate of hydrogen sulfide volatilization from water (ATSDR, 2006; Al

- Haddad et al., 198 9 ; Carroll and Mather 1989). Using a Henry's Law constant of 8.4 × 10 - 3 

### atm

- m 3 

### /mol at 20 °C and the EPI Suite estimation software (U.S. EPA, 200 9 ), the volatilization half

- lives of hydrogen sulfide are calculated to be 38 minutes for a model river 1 

### and 2.3 days for a model lake 2



### . Please note that h ydrogen sulfide is not a typical organic molecule and therefore caution must be used when interpreting the results of the EPI Suite program for this substance. These volatilization half

- lives may overestimate the rate at which volatilization may be occurring due to the fact that the EPI Suite software does not take into consideration the dissociation of hy drogen sulfide which increases with increasing pH above a pH of 5 (Balls and Liss, 1983). Hydrogen sulfide is a weak acid with a pKa value of 7.04 (O'Neil et al., 2006). The hydrogen sulfide molecule and the bisulfide anion (HS – 

### ) will both be present in waters at environmental pH (5

- 9) (SPARC, 2008; Balls and Liss, 1983). The ratio of bisulfide to hydrogen sulfide increases with increasing pH, with approximately 100% hydrogen sulfide at pH 5, approximately equal percentages of both species at pH 7, and approximately 100% bisulfide at pH 9 (SPARC, 2008; Balls and Liss, 1983). This pH

- dependent relationship is illustrated

1 Parameters for the model river are 1 m deep, flowing 1 m/sec, wind velocity of 5 m/sec. 2 Parameters for the model lake are 1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec.7 

### graphically in Figure 1

- 1. Bisulfide that forms from the dissociation of hydrogen sulfide in environmental waters will not volatilize since it is an ionic species.

Figure 1

- 1. Speciation of Hydrogen Sulfide as a Function of pH.

0 10 20 30 40 50 60 70 80 90 100

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 pH H2S HS


### The earth’s surface may act as a natural sink for hydrogen sulfide because soils have been shown to sorb this and other gases (Smith et al. 1973). The ad sorption capacity of hydrogen sulfide in 6 different soils ranged from 15.4 to 65.2 mg hydrogen sulfide per gram of soil in air

dry samples and from 11.0 to 62.5 mg hydrogen sulfide per gram of soil in moist samples (50% water holding capacity) (Smith et a l., 1973)

. The tests were conducted at room temperature with 1 gram samples of soils in sealed 65 mL containers into which 5 mL of gas were injected. The gas injection was repeated, if necessary until chromatographic analysis showed that little, if any, further sorption took place. All the soils had similar adsorption isotherms for hydrogen sulfide with the exception of a sandy Thurman series soil obtained from Iowa (>90% sand). This soil8 

### had the lowest capacity to adsorb hydrogen sulfide (and all the o ther gases tested), presumably due to the low surface area per unit weight of the soil.

1.6.2. Abiotic Degradation. Atmospheric oxidation of hydrogen sulfide by oxygen, ozone, or hydroxyl radicals produces sulfur dioxide (Hill, 1973). Measured rates f or the atmospheric oxidation via reaction with O 2 

### and O 3 

### are not available; however, half

- lives are expected to be less than 1 day (Hill, 1973). Hydrogen sulfide reaction rates with photochemically produced hydroxyl radicals was measured by Cox (1975) at a rate constant of 4.8 × 10 - 12 

### cm 3 

### /molecule

- sec. The author used this rate constant to calculate photooxidation lifetimes of 0.23 days using a summer daytime hydroxyl radical concentration of 10 7 

### molecules/cm 3 

### and 2.3 days using a year

round average hydroxy l radical concentration 10 6 

### molecules/cm 3



### . Bottenheim and Strausz (1980) concluded that reaction of atmospheric hydrogen sulfide with hydroxyl radicals is negligible during the winter based on an estimated lifetime of 41.9 days for that time of year.
Bas ed on the measured rate constant of 4.8 × 10 - 12 

### cm 3 

### /molecule

- sec reported by Cox (1975), an atmospheric photooxidation half

- life of 26.7 hours can be calculated assuming an atmospheric hydroxyl radical concentration of 1.5 × 10 6 

### molecules/cm 3 

### and a 12

- hour day . Hydrogen sulfide is not expected to undergo direct photolysis in the atmosphere (Cox, 1975). Hydrogen sulfide in environmental waters is oxidized by oxygen (O 2 

### ) to form sulfur dioxide and eventually sulfate. Reported oxidation half

- life values measured in air

- saturated solutions at 25 °C and pH 8 are 50 hours in fresh water and 26 hours in seawater (Millero et al., 1987). Other studies of oxidation rates of hydrogen sulfide in fresh and sea water have reported a variable range of half

- life values whichmay is in part be due to differences in experimental conditions including pH, temperature and ionic strength of the test solution and analytical methodology employed (Millero et al., 1987)9 

### 1.6.3. Biotic Degradation. Hydrogen sulfide is a major componen t of the natural sulfur cycle (WHO, 1981; Hill, 1973). Hydrogen sulfide is released into the environment by bacterial reduction of sulfate reduction processes and protein decomposition, especially under low

- oxygen (anaerobic) conditions and in locations w here readily decomposable organic matter is present (Boon, 1992; Hill, 1973). Higher levels of hydrogen sulfide are found in waters rich in organic matter such as flooded ground (e.g., swamps, bogs) (Pouliquen 2005). The reverse process, microbial oxidat ion of hydrogen sulfide to elemental sulfur or sulfate, is also observed (Jorgensen, 1982; Hill, 1973). Greater than 85% 35 

### S

- labeled hydrogen sulfide added to oxic water collected from the Black Sea chemocline was degraded after 1 day of incubation (Jorge nsen, 1982). Although transformation rates were similar in both the untreated and chloroform

- killed samples, differences in sulfate/thiosulfite accumulation indicated that bacterial processes were responsible for some of the transformation in the untreate d water. Approximately 90% of hydrogen sulfide added to chemocline water samples from Solar Lake, Sinai Peninsula was transformed by both abiotic and biological oxidation after 12 minutes incubation (Jorgensen, 1982).

1.6.4. Environmental Distribution As sessment. A model (U.S. EPA, 200 9 ) estimate was conducted of how, on a percentage basis, hydrogen sulfide would distribute in the environment if released at rates of 900, 100, and 0 kg per hour to the air, water, and soil environmental compartments, respe ctively. Measured physical

- chemical properties (melting point, boiling point, vapor pressure, water solubility, and Henry's law constant) were used as model input parameters. Model half

- life input values were assigned based on the photooxidation half

- lif e for air (26.7 hours) and a reported oxidation half

- time of 50 hours in fresh water for the water, soil, and sediment compartments. The advective flow rate was set to zero by selecting very large advection times (1 × 10 20 

### hours) for the air, water, and sed iment environmental compartments. A10 

### measured Henry's law constant of 8.4 × 10 - 3 

### atm

- m 3 

### /mol at 20°C and pH 7.1 from Carroll and Mather (1989) and a measured vapor pressure value of 1.5 × 10 4 

### mm Hg at 25°C from Daubert and Danner (2000) were used as input param eters to satisfy the requirements of the fugacity model. T he results of this model calculation suggest that for this release scenario (90% to air and 10% to water), most hydrogen sulfide will remain in the air with the rest partitioning to the water envir onmental compartment (85% air; 15% water; 0 % soil and sediment). The model partitioning results, half

- life inputs, and emissions inputs for each environmental compartment under this release scenario are shown in Table 1

- 2.

Table 1

- 2, Environmental Distri bution of Hydrogen Sulfide Based on 90% Release to air and 10% Release to Water

Compartment Mass amount (percent) Half

- life Values (hours) Emissions (kg/hr) Air 85.1% 26.7 900 Water 14.9% 50 100 Soil 0.00241% 50 0 Sediment 0.00482% 50 0

Source: EPI Suite, (U.S. EPA, 200 9 )



### The distribution estimate was also performed for equal emissions (1000 kg per hour) to the air, water, and soil environmental compartments. All other input parameters remained the same. The results of this calculation sugge st that for an equal release scenario, most hydrogen sulfide will partition to air and water with a small amount partitioning to soil (49% air; 41% water; 10% soil; 0% sediment). The model partitioning results, half

- life inputs, and emissions inputs for e ach environmental compartment under an equal release scenario are shown in Table
1

- 3.11 

### Table 1

- 3, Environmental Distribution of Hydrogen Sulfide Based on Equal Releases to Air, Water, and Soil

Compartment Mass amount (percent) Half

- life Values (hours) Emissions (kg/hr) Air 49% 26.7 1000 Water 40.7% 50 1000 Soil 10.3% 50 1000 Sediment 0.0132% 50 1000
Source: EPI Suite, (U.S. EPA, 200 9 )



### The volatilization half

- lives calculated within the fugacity model may overestimate the rate at which volatiliza tion may be occurring due to the fact that the EPI Suite software does not take into consideration the dissociation activity of hydrogen sulfide which increases with increasing pH above a pH of 5 (Balls and Liss, 1983).

1.6.5. Toxic Transformation Produ cts. Atmospheric oxidation of hydrogen sulfide by oxygen, ozone, or hydroxyl radicals produces sulfur dioxide (Hill, 1973). Sulfur dioxide is ultimately oxidized to form sulfate, which can be washed out of the atmosphere as sulfuric acid when dissolved i n rain droplets (Hill, 1973). The relative toxicities of hydrogen sulfide, sulfur dioxide, and sulfuric acid are reflected in the ACGIH (ACGIH, 2007) recommended limits for these chemi cals in workplace air (Table 1

- 4)

.12 

### Table 1

- 4. ACGIH Recommended Limit s for Hydrogen Sulfide, Sulfur Dioxide, and Sulfuric Acid in Workplace Air

ACGIH TLV
- TWA a ACGIH TLV
- STEL b Hydrogen sulfide 10 ppm (14.1 mg/m 3 ) 15 ppm (21.3 mg/m 3 ) Sulfur dioxide 2 ppm (5.3 mg/m 3 ) 5 ppm (13.3 mg/m 3 ) Sulfuric acid 0.2 mg/m 3 Not availabl e

a Threshold Limit Value

– Time

- Weighted Average (TLV

- TWA)

– The time

- weighted average concentration for a conventional 8

- hour workday and a 40

- hour workweek, to which it is believed that nearly all workers may be repeatedly exposed, day after day, for a w orking lifetime without adverse effect. b Threshold Limit Value

– Short

- Term Exposure Limit (TLV

- STEL)

– A 15

- minute time

- weighted average exposure that should not be exceeded at any time during a workday, even if the 8

- hour time

- weighted average is within th e TLV

- TWA. Source: ACGIH, 2007.


### 1 .7. REFERENCES ACGIH (American Conference of Governmental Industrial Hygienists). 2007. Hydrogen sulfide, sulfur dioxide, and sulfuric acid. In: Threshold limit values for chemical substances and physical agents and biological exposure indices. Cincinnati, OH: ACGIH. p. 34, 53.
Al

- Haddad A.A., M.S.E. Abdo, and S. A. Abdul

- Wahab. 1989. Evaluation of Henry's constant for H 2 

### S in water and sewage effluents. J. Environ. Sci. Health. Part A. 24(3):207

- 227. APHA (Ame rican Public Health Association). 1998. Method 4500 S 2

- 

### Sulfide. Standard methods for the examination of waste and wastewater. 20th ed. Washington, DC: 4

- 162 to 4

- 173. ATSDR (Agency for Toxic Substances and Disease Registry). 2006. Toxicological pro file for hydrogen sulfide

- update. Agency for Toxic Substances and Disease Registry, Centers for Disease Control and Prevention. PB2007100675. Available at: http://www.atsdr.cdc.gov/toxprofiles/tp114.html. Balls, P.W. and P.S. Liss. 1983. Exchange of H 2 

### S between water and air. Atmos. Environ. 17:735

- 742. Beauchamp, R.O. Jr., J.S. Bus, J.A. Popp, C.J. Boreiko, and D.A. Andjelkovich

. 1984. A critical review of the literature on hydrogen sulfide toxicity. CRC Crit. Rev. Toxicol. 13(1):25

- 97.
Boon , A.G. 1992. Sepacity in sewers: Causes, consequences and containment. J. Inst. Water Environ. Manage. 6:79

- 90. Bottenheim J.W. and O.P. Strausz. 1980. Gas

- phase chemistry of clean air at 55 degrees N latitude. Environ. Sci. Technol. 14:709

- 718. Carroll J.J. and A.E. Mather. 1989. The solubility of hydrogen sulphide in water from 0 to 90°C and pressures to 1 MPa. Geochim. Cosmochim. Acta. 53:1163

- 1170.13 

### CAS (Chemical Abstracts Service). 2007. On

- line search. American Chemical Society. Avai lable at: http://www.cas.org. ChemIDplus. 2008. Hydrogen sulfide (RN: 7783

- 06

- 4). ChemIDplus. U.S. National Library of Medicine. Available at: http://chem.sis.nlm.nih.gov/chemidplus/chemidheavy.jsp. Cox, R.A. 1975. Atmospheric photo

- oxidation re actions: The gas phase reaction of OH radicals with some sulphur compounds. Harwell: Environmental and Medical Sciences Division, United Kingdom Atomic Authority. AERE

- R8132. Daubert, T.E. and R.P Danner, Eds. 2000. Property constants: Hydrogen sul fide. In: Physical and thermodynamic properties of pure chemicals: Data compilation. Washington, DC: Taylor & Francis. Hill, F.B. 1973. Atmospheric sulfur and its links to the biota. Brookhaven Symp. Biol. 30:159

- 181. HSDB (Hazardous Substances Data Bank). 2007. Hydrogen sulfide. Hazardous Substances Data Bank. National Library of Medicine. Available at: http://toxnet.nlm.nih.gov. Jorgensen, B.B. 1982. Ecology of the bacteria of the sulphur cycle with special reference to anoxic

- oxic i nterface environments. Philos. Trans. R. Soc. Lond., B, Biol. Sci. 298:543

- 561. Lewis, R.J., Ed. 2001. Hydrogen sulfide. In: Hawley's condensed chemical dictionary. New York: John Wiley & Sons, Inc. p. 588

- 589. Lide, D.R., Ed. 2005. Hydrogen s ulfide. In: CRC handbook of chemistry and physics. Boca Raton: Taylor & Francis Group. p. 4

- 65. Millero, F.J., S. Hubinger, M. Fernandez, and S. Garnett. 1987. Oxidation of H 2 

### S in sea water as a function of temperature, pH and ionic strength. Envi ron. Sci. Technol. 21:439

- 443. O'Neil, M.J., P.E. Heckelman, C.B. Koch, and K.J. Roman, Eds. 2006. Hydrogen sulfide. In: The Merck index. Whitehouse Station, NJ: Merck & Co. Inc. p. 831

- 832. Pouliquen, F., C. Blanc, E. Arretz, et al. 2005. Hydr ogen sulfide. In: Ullmann's encyclopedia of industrial chemistry. Wiley

- VCH Verlag GmbH & Co. Available at: http://www.mrw.interscience.wiley.com. Smith, K.A., J.M. Bremner, and M.A. Tabatalag. 1973. Sorption of gaseous atmospheric pollutants by so ils. Soil Sci. 116:313

- 319. SPARC. 2008. SPARC online calculator

– Version 4.1. University of Georgia and U.S. Environmental Protection Agency. Available at: http://sparc.chem.uga.edu/sparc/. Ulmann’s, 1989. Ullmann’s Encyclopedia of Industrial Ch emistry, Fifth Revised Edition, VCH Publishers, Weinheim, Germany. Vol A13, p476.14 

### U.S. EPA (U.S. Environmental Protection Agency). 1993. Report to Congress on hydrogen sulfide air emissions associated with the extraction of oil and natural gas. Rese arch Triangle Park, NC: U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards. EPA453R93045. PB94131224.
U.S. EPA

. 2007a. Inventory update reporting. U.S. Environmental Protection Agency. Available at: http://www.epa.go v/oppt/iur/. U.S. EPA. 2007b. TRI E xplorer: Providing access to EPA’s toxics release inventory data. Washington, DC: U.S. Environmental Protection Agency, Toxics Release Inventory. Available at: http://www.epa.gov/triexplorer/.
U.S. EPA. 200 9 . E stimation Programs Interface Suite TM 

### v4.0. U.S. Environmental Protection Agency. Available at: http://www.epa.gov/oppt/exposure/pubs/episuitedl.htm. Weil, E.D., S.R. Sandler, and M. Gernon. 2006. Sulfur compounds. In: Kirk

- Othmer encyclopedia of che mical technology. John Wiley & Sons, Inc. Available at: http://www.mrw.interscience.wiley.com. WHO (World Health Organization). 1981. Environmental health criteria for hydrogen sulfide. World Health Organization. International Programme on Chemical Safety. Available at: http://www.inchem.org/documents/ehc/ehc/ehc019.htm.15 

### 2. ECOLOGICAL HAZARD ASSESSMENT
2.1. SUMMARY Hydrogen sulfide is a biologically active compound that is of toxicological concern primarily when in a neutral state (H 2 

### S) as o pposed to an ionic state (HS - 

### , S - 2 

### ) (U.S. EPA, 1986). Hydrogen sulfide is expected to present a significant concern for adverse effects on the environment. This conclusion is based on both acute, chronic and early

- life stage e xperimental toxicity values for aquatic organisms

. As presented in Table 2

- 1, acute toxicity values (96

- hour LC 50 

### values) for freshwater fish ranged from 0.016 to 0.0448 mg/L, indicating high aquatic toxicity; for estuarine/marine fish, a single 96

- hour LC 50 

### value of 1.43 mg/L was a vailable. Chronic toxicity values for freshwater fish ranged from a 6

- week Lowest Observed Effect Concentration (LOEC) (growth rate) of 0.0005 mg/L in a tropical fish Mystus nemurus to a 430

- day LOEC (final weight) of 0.009 mg/L for goldfish. These obser ved adverse effects noted for the chronic exposure of freshwater fish at the above low concentrations also indicate high aquatic toxicity for hydrogen sulfide. Additionally, in early

- life stage toxicity testing with eggs, fry, and juveniles of various fre shwater fish species, endpoint values ranged from a 96

- hour LC 50 

### of <0.002 mg/L (yellow perch sac fry) to a 96

- hour LC 50 

### value of 0.0536 mg/L (fathead minnow). For estuarine/marine fish, a 24

- hour LC 100 

### of 2.9 mg/L was reported for Black Sea turbot eggs. Hydrogen sulfide also demonstrated high toxicity to aquatic invertebrates. Ninety

- six

hour LC 50 

### values for freshwater invertebrates ranged from 0.02 to 1.07 mg/L, and 48

- to 96

- hour EC/LC 50 

### values for estuarine/marine invertebrates ranged from 0.01 to 0. 332 mg/L. Chronic values for freshwater invertebrates ranged from a 65

- day LOEC (reproduction) of 0.0031 mg/L
to a 10

- day LC 50 

### value of 0.042 mg/L, both for the amphipod Gammarus pseudolimnaeus

. For estuarine/marine invertebrates, the only chronic endpoi nt value available was a 49

- day LOEC (based on decreased wet weight) of 1.12 mg/L for the sea urchin. Additionally, in early

- life16 

### stage toxicity testing, a 96

- hour LC 50 

### value of 0.034 mg/L was available for juvenile crayfish (freshwater species); for estu arine/marine invertebrates, 48

- hour LC 50 

### values of 0.0087 mg/L and 0.0185 mg/L were available for white shrimp larvae and juveniles, respectively. No experimental toxicity data were available for algae. Hydrogen sulfide is not expected to bioaccumulat e significantly in aquatic organisms. The bioconcentration factor (BCF) is approximately 3 (U.S. EPA, 2009).

2.2. ECOLOGICAL TOXICITY Databases searched to identify studies on ecological toxicity were ECOTOX (2007) (which contains three databases: AQUI RE, PHYTOTOX, and TERRETOX), the Office of Pesticide Programs (OPP) Environmental Fate and Effects Division (EFED) Pesticide Ecotoxicity Database, and the Hazardous Substances Databank (HSDB, 2007). In addition, the TOXLINE database (TOXLINE, 2007) was se arched to identify additional aquatic toxicity studies and population effects studies . No laboratory data on algal toxicity or toxicity to terrestrial animals and plants were found. Table 2

- 1 presents the experimental values for acute and chronic toxicit y of hydrogen sulfide to aquatic organisms and toxicity to terrestrial organisms. The lowest experimental endpoint values available from a given study were selected for inclusion in the table. If multiple values were available for different life stages w ithin a given study (e.g., multiple LC 50 

### values for fish eggs, and multiple LC 50 

### values for juveniles within the same study), then the lowest values available for each life stage were selected for inclusion in Table 2

- 1 (e.g., lowest LC 50 

### for fish eggs and lowest LC 50 

### for juveniles). Endpoint values for durations longer than 96 hours but shorter than 28 days (for fish) and 21 days (for aquatic invertebrates) were included in the chronic toxicity sections of Table 2

- 1, although it is acknowledged that toxic ity tests with durations less than 28 days and aquatic invertebrate toxicity tests with durations less than 2117 

### days are typically not considered chronic tests. When interpreting results of hydrogen sulfide aquatic toxicity testing, care should be taken to consider the potential effects of pH, temperature, and dissolved oxygen concentration in combination with hydrogen sulfide exposure. As indicated in Section 1.6.1, the proportion of hydrogen sulfide is dependent on the pH of the water, with more basic pH levels leading to decreased amounts of hydrogen sulfide and increased amounts of the bisulfide anion (HS - 

### ). Additionally, as stated in Section 1.6.1, increasing temperature generally increases the rate of hydrogen sulfide volatilization from water. Rega rding dissolved oxygen, some data indicate that hydrogen sulfide toxicity can increase when combined with hypoxic test conditions (Kang & Matsuda, 1994).

Table 2

- 1. Ecological Toxicity Values for Hydrogen Sulfide a
Species Duration and Test Endpoint pH Du ring Test e Experimental Type b,c Value (mg/L) d Reference 

## Acute aquatic toxicity Algae

- No data Freshwater invertebrate Freshwater amphipod ( Gammarus pseudolimnaeus ) 96

- hour LC 50 7.9 F, M 0.021 Oseid and Smith , 1974a (Table 2); Smith and Oseid, 1975 (T able 2); U.S. EPA, 1976 (Table 115) Freshwater amphipod ( G. pseudolimnaeus ) 96

- hour LC 50 7.5 F, M 0.059 Oseid and Smith, 1974b (Table 14); U.S. EPA, 1976 (Table 122) Crayfish ( Cambarus diogenes )

– sub

- adult 96

- hour LC 50 7.70 (mean) F, M 0.070 U.S. EPA, 1 976 (Table 103) Ephemeroptera ( Baetis vagans ) 96

- hour LC 50 7.6 F, M 0.020 Oseid and Smith, 1974b (Table 14); U.S. EPA, 1976 (Table 122) Ephemeroptera ( Ephemera simulans ) 96

- hour LC 50 7.4 F, M 0.316 Oseid and Smith, 1974b (Table 14); U.S. EPA, 1976 (Table 122) Ephemeroptera ( Hexagenia limbata ) 96

- hour LC 50 7.7 F, M 0.030 U.S. EPA, 1976 (Table 118) Ephemeroptera ( H. limbata ) 96

- hour LC 50 7.7 F, M 0.111 Oseid and Smith, 1974b (Table 14); U.S. EPA, 1976 (Table 122) Amphipod ( Crangonyx richmondensis laurent ianus ) 96

- hour LC 50 7.4 F, M 0.840 Oseid and Smith, 1974b (Table 14); U.S. EPA, 1976 (Table 122) Isopod ( Assellus militaris ) 96

- hour LC 50 7.5 F, M 1.070 Oseid and Smith, 1974b (Table 14); U.S. EPA, 1976 (Table 122) Freshwater fish Fathead minnow ( P. pro melas ) 96

- hour LC 50 8.693 (mean) g F, M 0.0149 Broderius et al., 1977 (Table 3)18 Species Duration and Test Endpoint pH Du ring Test e Experimental Type b,c Value (mg/L) d Reference Fathead minnow ( P. promelas ) 96

- hour LC 50 7.9 F, M 0.0160 U.S. EPA, 1976 (Table 6) Fathead minnow ( P. promelas ) 96

- hour LC 50 7.698 (mean) F, M 0.0382 Broderius et al., 1977 (T able 3) Rainbow trout ( S. gairdneri )

– fry 96

- hour TL 50 j 7.6

- 8.0 F, M 0.0200 Smith and Oseid, 1972 (page 718) Bluegill ( L. macrochirus ) 96

- hour LC 50 7.8

- 8.0 F, M 0.0448 Smith et al., 1976a (Table 2) White sucker ( C. commersoni ) 96

- hour LC 50 7.8 F, M 0. 0185 U.S. EPA, 1976 (Table 101) Goldfish ( C. auratus ) 96

- hour LC 50 7.69 (mean) F, M 0.0440 U.S. EPA, 1976 (Table 40) Estuarine/marine invertebrate Saltwater shrimp ( Penaeus indicus ) 96

- hour LC 50 6.0

- 6.3 F, M 0.0630 Gopakumar and Kuttyamma, 1996 (Table 1 ) Saltwater shrimp ( Metapenaeus dobsoni ) 96

- hour LC 50 6.0

- 6.3 F, M 0.0770 Gopakumar and Kuttyamma, 1996 (Table 1) Saltwater mussel ( Mytilus edulis ) 48

- hour EC 50 7.9

- 8.1 F, M 0.010 p Knezovich et al., 1996 Sea urchin ( Strongylocentrotus purpuratus ) 48

- ho ur EC 50 7.9

- 8.1 F, M 0.019 p Knezovich et al., 1996 Adult amphipod ( Eohaustorius estuarius ) 48

- hour LC 50 7.9

- 8.1 F, M 0.160 p Knezovich et al., 1996 Adult amphipod ( Rhepoxynius abronius ) 48

- hour LC 50 7.9

- 8.1 F, M 0.332 p Knezovich et al., 1996 Estuarine/ma rine fish California killifish ( Fundulus parvipinnis ) 96

- hour LC 50 8.3 F, M 1.43 Bagarinao and Vetter, 1993 

## Chronic aquatic toxicity Algae

- No data Freshwater invertebrate Freshwater amphipod ( G. pseudolimnaeus ) 65

- day LOEC (reproduction) Not report ed F, M 0.0031 Smith and Oseid, 1975 (Table 3) Crayfish ( P. clarkii ) 447

- day NOEC (survival) 7.69

- 7.73 F, M 0.0041 U.S. EPA, 1976 (Table 106) Ephemeroptera ( H. limbata )

– nymph 138

- day NOEC (survival) 7.8

- 8.2 F, M 0.0129 U.S. EPA, 1976 (Table 126) Fresh water amphipod ( G. pseudolimnaeus ) 10

- day LC 50 k 7.5 o F, M 0.0420 Oseid and Smith, 1974b (Table 3) Freshwater amphipod ( G. pseudolimnaeus ) 18

- day LC 50 k 7.5 o F, M 0.0110 Oseid and Smith, 1974a (page 821) Freshwater fish Bluegill ( L. macrochirus ) 97

- day LO EC (reproduction) Not reported F, M 0.0007 Smith and Oseid, 1975 (Table 3); U.S. EPA, 1976 (Table 59) Bluegill ( L. macrochirus ) 97

- day LOEC (reproduction) 7.6

- 8.0 F, M 0.0010 Smith et al., 1976a (Table 7) Bluegill ( L. macrochirus ) 97

- day LOEC (# eggs/fem ale) Not reported F, M 0.0014 Smith and Oseid, 1974 (Table 2)
Fathead minnow ( P. promelas ) 274

- to 297

- day mean NOEC (survival) 7.7

- 7.9 F, M 0.0036 Smith et al., 1976b (Table V)19 Species Duration and Test Endpoint pH Du ring Test e Experimental Type b,c Value (mg/L) d Reference Fathead minnow ( P. promelas ) 56

- to 112

- day mean NOEC (growth) 7.7

- 7.9 F, M 0.0042 Smith et al., 1976b (Table V)
Fathead minnow ( P. promelas ) 274

- to 297

- day mean NOEC (fecundity) 7.7

- 7.9 F, M 0.0059 Smith et al., 1976b (Table V)

Fathead minnow ( P. promelas ) 297

- day LOEC (adult survival to spawning) Not reported F, M 0.0061 Smit h and Oseid, 1974 (Table 2)
Fathead minnow ( P. promelas ) 37

- day LOEC (survival) 7.67

- 7.85 F, M 0.0078 U.S. EPA, 1976 (Table 14) Goldfish ( C. auratus ) 430

- day LOEC (final weight) 7.57

- 7.63 F, M 0.0090 U.S. EPA, 1976 (Table 46)
Freshwater tropical fish ( Mystus nemurus ) 6

- week LOEC (decreased growth rate and decreased liver somatic index) 6.9

- 7.5 F, M f 0.0005 Hoque et al., 1998 (Table II)

Brook trout ( S. fontinalis )

– adult 76

- day LOEC (# eggs/female) Not reported F, M 0.0055 Smith and Oseid, 1974 (Table 2) Brook trout ( S. fontinalis )

– adult 120

- day LOEC (reproduction) 7.78 (mean) F, M 0.0055 U.S. EPA, 1976 (Table 82) Walleye ( S. vitreum vitreum ) 225

- day LOEC (survival) 7.59

- 7.71 F, M 0.0051 U.S. EPA, 1976 (Table 67) Estuarine/marine invertebrate
Sea urchin ( Lytechinus pictus ) 49

- day LOEC (decreased wet weight) 8.0 F, M 1.121 Thompson et al., 1991 (Figure 5B) Estuarine/marine fish Atlantic salmon ( Salmo salar ) 18

- week LOEC (liver damage) Not reported S, M 0.238 Kiemer et al., 1995 (Figure 9) 

## Early Life Stage Toxicity Testing Freshwater invertebrate Crayfish ( Procambarus clarkii )

– juvenile 96

- hour LC 50 7.71 (mean) F, M 0.034 U.S. EPA, 1976 (Table 103) Freshwater fish Fathead minnow ( Pimephales promelas )

– eggs 96

- hour LC 50 7.9 F, M 0.0190 U.S. E PA, 1976 (Table 3) Fathead minnow ( P. promelas )

– eggs 96

- hour LC 50 7.9 F, M 0.0536 Smith et al., 1976b (Table II) Fathead minnow ( P. promelas )

– eggs 84

- day LOEC (growth and survival) Not reported F, M 0.0065 Smith and Oseid, 1975 (Table 3) Fathead min now ( P. promelas )

– swim

- up fry 96

- hour LC 50 Not reported F, M 0.0070 Smith and Oseid, 1974 (Table 5); Smith and Oseid, 1975 (Table 2) Fathead minnow ( P. promelas )

– fry 96

- hour LC 50 7.9 F, M 0.0066 U.S. EPA, 1976 (Table 3) Fathead minnow ( P. promelas )

– fry 96

- hour LC 50 7.9 F, M 0.0107 Smith et al., 1976b (Table II) Fathead minnow ( P. promelas )

– juvenile 96

- hour LC 50 7.9 F, M 0.0179 U.S. EPA, 1976 (Table 5)20 Species Duration and Test Endpoint pH Du ring Test e Experimental Type b,c Value (mg/L) d Reference Fathead minnow ( P. promelas )

– juvenile 96

- hour LC 50 7.9 F, M 0.0243 Smith et al., 1976b (Tabl e II) Rainbow trout ( Salmo gairdneri )

– eggs 96

- hour TL 50 j 7.6

- 8.0 F, M 0.0490 Smith and Oseid, 1972 (Table 2) Rainbow trout ( S. gairdneri )

– fry 20

- day LC 50 7.7 (mean) F, M 0.0056 U.S. EPA, 1976 (Table 91) Rainbow trout ( S. gairdneri )

– swim

- up fry 20

- d ay LC 50 Not reported F, M 0.0060 Smith and Oseid, 1974 (Table 5) Rainbow trout ( S. gairdneri )

– juvenile 96

- hour LC 50 8.0 F, M 0.0070 Fung and Bewick, 1980 (Table 4) n Rainbow trout ( S. gairdneri )

– juvenile 96

- hour LC 50 7.7 (mean) F, M 0.0125 U.S. EPA, 1 976 (Table 87) Rainbow trout ( S. gairdneri )

– juvenile 96

- hour LC 50 Not reported F, M 0.0130 Smith and Oseid, 1974 (Table 5) Bluegill ( Lepomis macrochirus )

– eggs 96

- hour LC 50 7.8

- 8.0 F, M 0.0190 Smith et al., 1976a (Table 2) Bluegill ( L. macrochirus )

– swim

up fry 96

- hour LC 50 7.8

- 8.0 F, M 0.0086 U.S. EPA, 1976 (Table 50) Bluegill ( L. macrochirus )

– swim

up fry 96

- hour LC 50 Not reported F, M 0.0090 Smith and Oseid, 1975 (Table 2) Bluegill ( L. macrochirus )

– fry 96

- hour LC 50 7.8

- 8.0 F, M 0.0131 Smith e t al., 1976a (Table 2) Bluegill ( L. macrochirus )

– fry 8

- day LC 50 7.8

- 8.0 F, M 0.0128 Smith et al., 1976a (Table 2) Bluegill ( L. macrochirus )

– juvenile 96

- hour LC 50 7.8

- 8.0 F, M 0.0478 Smith et al., 1976a (Table 2) Bluegill ( L. macrochirus )

– juvenile 8

- to 10

- day LC 50 7.8

- 8.0 F, M 0.0480 Smith et al., 1976a (Table 2) Whitefish ( Coregonus clupeaformis )

– sac fry 96

- hour LC 50 8.0 F, M 0.0020 Fung and Bewick, 1980 (Table 4) n Yellow perch ( Perca flavescens )

– sac fry 96

- hour LC 50 8.0 F, M <0.0020 Fung an d Bewick, 1980 (Table 4) n Brown trout ( Salmo trutta )

– sac fry 96

- hour LC 50 7.0

- 7.2 F, M 0.0070 Reynolds and Haines, 1980 (Table 2) Walleye ( Stizostedion vitreum vitreum )

– eggs 96

- hour TL 50 j 7.6

- 8.0 F, M 0.0520 Smith and Oseid, 1972 (Table 2) Walleye ( S. vitreum vitreum )

– eggs 10

- day TL 50 j 7.6

- 8.0 F, M 0.0220 Smith and Oseid, 1972 (Table 2) Walleye ( S. vitreum vitreum )

– fry 96

- hour TL 50 j 7.6

- 8.0 F, M 0.0070 Smith and Oseid, 1972 (page 715) Walleye ( S. vitreum vitreum )

– juvenile 96

- hour LC 50 7.8

- 8.0 F, M 0.0166 U.S. EPA, 1976 (Table 65) Walleye ( S. vitreum vitreum )

– juvenile 96

- hour LC 50 Not reported F, M 0.0200 Smith and Oseid, 1974 (Table 5) Northern pike ( Esox lucius )

– eggs 96

- hour TL m j 7.3

- 8.0 F, M l 0.0220 Adelman and Smith, 1970 (Table 4) N orthern pike ( E. lucius )

– eggs 13

- day TL m j 7.3

- 8.0 F, M l 0.0240 Adelman and Smith, 1970 (Table 4) Northern pike ( E. lucius )

– sac fry 96

- hour TL m j 7.3

- 8.0 F, M l 0.0080 Adelman and Smith, 1970 (Table 6)21 Species Duration and Test Endpoint pH Du ring Test e Experimental Type b,c Value (mg/L) d Reference Northern pike ( E. lucuis )

– sac fry 96

- hour LC 50 No t reported F, M 0.0260 Smith and Oseid, 1974 (Table 5) Largemouth bass ( Micropterus salmoides )

– sac fry 96

- hour LC 50 8.0 F, M 0.0110 Fung and Bewick, 1980 (Table 4) n White sucker ( Catostomus commersoni )

– eggs 96

- hour TL 50 j 7.6

- 8.0 F, M 0.0280 Smith and Oseid, 1972 (Table 2) White sucker ( C. commersoni )

– eggs 12

- day TL 50 j 7.6

- 8.0 F, M 0.0190 Smith and Oseid, 1972 (Table 2) White sucker ( C. commersoni )

– fry 96

- hour TL 50 j 7.6

- 8.0 F, M 0.0130

- 0.0260 Smith and Oseid, 1972 (page 718) White sucker ( C. com mersoni )

– juvenile 96

- hour LC 50 Not reported F, M 0.0190 Smith and Oseid, 1974 (Table 5) Brook trout ( Salvelinus fontinalis )

– swim

- up fry 96

- hour LC 50 Not reported F, M 0.0216 Smith and Oseid, 1975 (Table 2) Brook trout ( S. fontinalis )

– juvenile 96

- ho ur LC 50 7.85 F, M 0.0156 U.S. EPA, 1976 (Table 76) Brook trout ( S. fontinalis )

– juvenile 96

- hour LC 50 Not reported F, M 0.0170 Smith and Oseid, 1974 (Table 5) Goldfish ( Carassius auratus )

– eggs 72

- hour LC 50 Not reported F, M 0.0200 Smith and Oseid, 197 4 (Table 5) Goldfish ( C. auratus )

– eggs 96

- hour LC 50 Not reported F, M 0.0220 Smith and Oseid, 1975 (Table 2) Goldfish ( C. auratus )

– eggs 430

- day LOEC (growth and survival) Not reported F, M 0.0090 Smith and Oseid, 1975 (Table 3) Estuarine/marine inve rtebrate White shrimp ( Metapenaeus monoceros )

– larvae 48

- hour LC 50 8.0

- 8.4 h F, M 0.0087 Kang and Matsuda, 1994 (Table 1) White shrimp ( M. monoceros )

– juvenile 48

- hour LC 50 8.0

- 8.2 i F, M 0.0185 Kang and Matsuda, 1994 (Table 1) Estuarine/marine fish Bl ack Sea turbot ( Rhombus maeoticus )

– eggs 24

- hour LC 100 Not reported Not reported 2.9 Ivanov et al., 1976 

## Terrestrial toxicity and phytotoxicity Avian species

- No data Terrestrial invertebrate

- No data Plants

- No data

a The lowest experimental end point values available from a given study were selected for inclusion in the table. If multiple values were available for different organism life stages (e.g., multiple LC 50 values for fish eggs, and multiple LC 50 values for juveniles) within a given stud y, then the lowest values available for each life stage from that study were selected for inclusion in Table 2

- 1 (e.g., lowest LC 50 for fish eggs and lowest LC 50 for juveniles) except where noted. Endpoint values for fish toxicity tests shorter than 96 ho urs in duration (e.g., a fish 24

- hour LC 50 value) were not included in Table 2

- 1. Endpoint values for durations longer than 96 hours but shorter than 28 days (for fish) and 21 days (for aquatic invertebrates) were included in the acute toxicity sections o f Table 2

- 1. b For freshwater tests, water hardness was within the accepted range (50

- 250 mg/L as CaCO 3 ) unless noted otherwise.
c Experiment type: S = static, F = flow

- through, M = measured d mg/L = ppm
e Study reports did not always indicate whether repor ted pH values represented mean values. f Water hardness was not reported. g pH was 8.693, which is outside the accepted range of 6.5

- 8.0. h pH was 8.2±0.2, which is slightly outside the accepted range of 6.5

- 8.0.22 i pH was 8.1±0.1, which is slightly outside the accepted range of 6.5

- 8.0. j TL 50 or TL m is defined as the median tolerance limit. k The study duration is less than the 21

- day duration that is typical of aquatic invertebrate chronic toxicity studies. l Water hardness was reportedly 290

- 300 ppm.
m The chemi cal may not be soluble enough to measure this predicted effect.
n LC 50 values for different life stages of four different fish species were reported. Because of the consistency of these LC 50 values across fish life stages (all were less than 0.063 mg/L), o nly the single lowest LC 50 value for each species (regardless of organism life stage) was included here in Table 2

- 1.
o This is the pH of the well water used in the test; pH during the actual test was not reported. p The study reported the endpoint values as total sulfides, and stated that “the concentration of hydrogen sulfide is approximately 9

- 10% of the total sulfide concentration under the conditions of these tests.” Therefore, the value reported here represents 10% of the value for total sulfides.



### 2. 2.1. Acute Toxicity. Acute toxicity values are presented in Table 2

- 1. Acute toxicity values (96

- hour LC 50 

### values) for freshwater fish ranged from 0.0149 to 0.0448 mg/L. Acute toxicity values (96

- hour LC 50 

### values) for freshwater invertebrates ranged fro m 0.02 to 1.07 mg/L. For estuarine/marine invertebrates, acute toxicity values (48

- or 96

- hour EC or LC 50 

### values) ranged from 0.01 to 0.332 mg/L. For estuarine/marine fish, a 96

- hour LC 50 

### value of 1.43 mg/L was available.

2.2.2. Chronic Toxicity. Chron ic toxicity values are presented in Table 2

- 1. Chronic toxicity values (37

- to 430

- day LOECs) for freshwater fish ranged from 0.0005 mg/L (freshwater tropical fish Nystus nemurus ) to 0.009 mg/L (goldfish). For freshwater invertebrates, chronic toxicity

v alues (65

- day LOEC, 138

- or 447

- day No Observed Effect Concentrations [NOECs], 10

- and
18

- day LC 50 

### values) ranged from 0.0031 to 0.042 mg/L. For estuarine/marine fish, experimental data were available only for Atlantic salmon; for this species, an 18

- week LOEC (based on liver damage) of 0.238 mg/L was observed. For estuarine/marine invertebrates, experimental data were available only for a species of sea urchin; a 49

- day LOEC (based on decreased wet weight) of 1.121 mg/L was observed.

2.2.3. Early
- Life S tage Toxicity Testing. Endpoint values from early

- life stage toxicity tests are presented in Table 2

- 1. For freshwater invertebrates, a 96

- hour LC 50 

### value of 0.034 mg/L for23 

### juvenile crayfish was observed. For freshwater fish eggs, 96

- hour LC 50 

### values (f or species including fathead minnow, rainbow trout, bluegill, walleye, Northern pike, white sucker, and goldfish) ranged from 0.0190 mg/L (rainbow trout and bluegill) to 0.0536 mg/L (fathead minnow). Additionally, 10

- , 12

- , and 13

- day median tolerance lim its (TL m 

### or TL 50 

### ) of 0.022, 0.019, and 0.024 mg/L were reported for walleye, white sucker, and Northern pike eggs, respectively, and 84

- and 430

- day LOEC values (growth and survival) of 0.0065 and 0.009 mg/L were reported for fathead minnow and goldfish eg gs, respectively. For freshwater fish fry, 96

- hour LC 50 

### values for fry ranged from <0.002 mg/L (yellow perch) to 0.026 mg/L (Northern pike). Additionally, 20

- day LC 50 

### values of 0.006 and 0.0056 mg/L were reported for rainbow trout fry, and an 8

- day LC 50 

### of 0.0128 mg/L was reported for bluegill fry. For freshwater fish juveniles, 96

- hour LC 50 

### values ranged from 0.007 mg/L (rainbow trout) to 0.0478 mg/L (bluegill). Additionally, an 8

- to 10

- day LC 50 

### of 0.048 mg/L was reported for bluegill juveniles.
For estuarine/marine fish, a 24

- hour LC 100 

### of 2.9 mg/L was reported for Black Sea turbot eggs. For estuarine/marine invertebrates, 48

- hour LC50 values of 0.0087 and 0.0185 mg/L were available for white shrimp larvae and juveniles, respectively.

2.2.4. Terres trial Toxicity and Phytotoxicity. No terrestrial toxicity or phytotoxicity data were available.

2.2.5. Population Effects . No data on population effects were located.

2.2.6. Bioaccumulation Potential. Bioaccumulation in aquatic organisms can be esti mated using the BCF, which describes the degree to which a chemical can be concentrated in the tissues of an organism. Measured BCFs were not located in HSDB; thus, a BCF of approximately 3 was24 

### calculated using EPI Suite v4.0 (U.S. EPA, 2009). Based on t he calculated BCF, hydrogen sulfide is not expected to bioaccumulate in the tissue of aquatic organisms.

2.3. REFERENCES Adelman, I.R. and L.L. Smith. 1970. Effect of hydrogen sulfide on northern pike eggs and sac fry. Trans. Am. Fish. Soc. 3: 501

- 50 9. Bagarinao, T. & R.D. Vetter. 1993. Sulphide tolerance and adaptation in the California killifish, Fundulus parvipinnis , a salt marsh resident. J. of Fish Biology, 42: 729

- 748. Broderius, S.J., L.L. Smith and D.T. Lind. 1977. Relative toxicity of free cyanide and dissolved sulfide forms to the fathead minnow ( Pimephales promelas ). J. Fish. Res. Board Can. 34: 2323

- 2332. ECOTOX. 2007. ECOTOX user guide: ECOTOXicology Database System. Version 4.0, Released February 2007. Available at: http://www.epa.gov/ecotox/. Fung, D.K. and P.H. Bewick. 1980. Short

- term toxicity of aqueous hydrogen sulfide to representative fish species of Lake Huron. In: Aquatic toxicology. J.G. Eaton, P.R. Parrish, and A.C. H endricks, Eds. American Society for Testing and Materials, ASTM STP 707. p. 377

- 396. Gopakumar, G. and V.J. Kuttyamma. 1996. Effect of hydrogen sulphide on two species of penaeid prawns Penaeus indicus (H. Milne Edwards) and Metapenaeus dobsoni (Miers ). Bull. Environ. Contam. Toxicol. 57: 824

- 828. Hoque, M.T., F.M. Yusoff, A.T. Law, and M.A. Syed. 1998. Effect of hydrogen sulphide on liver somatic index and Fulton’s condition factor in Mystus nemurus . J. Fish Biol. 52(1): 23

- 30. HSDB (Hazardous Substances Databank) 2007. Part of the National Library of Medicine's Toxicology Data Network (TOXNET 7 ). Bethesda, MD. Available at: http://toxnet.nlm.nih.gov/cgi

- bin/sis/htmlgen?HSDB

. Ivanov, V.N., Usenko, T.G. & A.V. Parkhomenko. 1976. Effect of hydrogen sulfide on the survival rate of eggs and embryonal mitoses of the black sea turbot. Hydrobiol. J. 12(2): 60

- 62. Kang, J.C. and O. Matsuda. 1994. Combined effects of hypoxia and hydrogen sulfide on early developmental stages of white shrimp Metapenaeus monoceros . J. Facul. Appl. Biol. Sci., Hiroshima Univ., 33: 21

- 27. Kiemer, M.C.B., K.D. Black, D. Lussot, A.M. Bullock, and I. Ezzi. 1995. The effects of chronic and acute expo sure to hydrogen sulphide on Atlantic salmon ( Salmo salar L.). Aquaculture. 135: 311

- 327. Knezovich J.P., Steichen D.J., Jelinksi J.A. & S.L. Anderson. 1996. Sulfide tolerance of four marine species used to evaluate sediment and pore

- water toxicity. Bull Environ Contam Toxicol 57: 450

- 457.25 

### Oseid, D.M. and L.L. Smith. 1974a. Chronic toxicity of hydrogen sulfide to Gammarus pseudolimneaus . Trans. Am. Fish. Soc. 4: 819

- 822. Oseid, D.M. and L.L. Smith. 1974b. Factors influencing acute toxicity es timates of hydrogen sulfide to freshwater invertebrates. Water Res. 8: 739

- 746. Reynolds, F.A. and T.A. Haines. 1980. Effects of chronic exposure to hydrogen sulphide on newly hatched brown trout Salmo trutta L. Environ. Pollut. 22: 11

- 17. Smith, L.L . and D.M. Oseid. 1972. Effects of hydrogen sulfide on fish eggs and fry. Water Res. 6(6): 711

- 720. Smith, L.L. and D.M. Oseid. 1974. Effect of hydrogen sulfide on development and survival of eight freshwater fish species. Scientific Journal Series , Minnesota Agricultural Experiment Station, St. Paul, MN. Paper No. 8340. Smith, L.L. and D.M. Oseid. 1975. Chronic effects of low levels of hydrogen sulfide on freshwater fish. Prog. Water Tech. 7(3/4): 599

- 605. Smith, L.L., D.M. Oseid, G.L. Kim ball, and S.M. El

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