Reaction mass of disodium sulphide and sodium hydrogensulphide

Sediment toxicity

Administrative data

Endpoint:

sediment toxicity: long-term

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Well performed study. Effect concentrations based on measured pore water sulfide concentrations. Concentrations were relatively constant during the 49-day exposure.

Data source

Reference

Reference Type:

publication

Title:

Sublethal effects of hydrogen sulfide in sediments on the urchin Lytechinus pictus.

Author:

Thompson B, Bay S, Greenstein D, Laughlin J

Year:

1991

Bibliographic source:

Marine Environmental Research 31: 309-321.

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

A sodium sulfide solution was pumped to the sub-sediment reservoir (0.5 mL/min, reservoir solutions replenished every 2-3 days), where it diffused up through the sediment layer. Clean aerated seawater flowed above the sediment layer (flow-through system).

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

1313-84-4

Cas Number:

1313-84-4

IUPAC Name:

1313-84-4

Constituent 2

Reference substance name:

sodium sulfide nonahydrate

IUPAC Name:

sodium sulfide nonahydrate

Details on test material:

- Name of test material (as cited in study report): Na2S.9H2O
- No further details provided

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Samples were taken from each aquarium at the beginning and end of the 49-d exposure period.
A syringe fitted with a 5-µm filter was inserted 1 cm into the sediment and 5 mL of pore water was withdrawn in each of the three replicate samples. It was assumed that the water was an integrated sample of pore water from about the top 2 cm of the sediment.

Test substrate

Vehicle:

no

Details on sediment and application:

see test conditions and description of mehod

Test organisms

Test organisms (species):

other: Lytechinus pictus (sea urchin)

Details on test organisms:

TEST ORGANISM
- Common name: sea urchin
- Source: collected by otter trawl in northern Santa Monica Bay, California, USA
- Age of animals at beginning of exposure: test diameter = 14-23 mm (adult)
- Feeding during test: no data

ACCLIMATION
- Acclimation period: 30 d
- Acclimation conditions (same as test or not): yes
- Type and amount of food: no data
- Feeding frequency: no data

Study design

Study type:

laboratory study

Test type:

flow-through

Water media type:

saltwater

Type of sediment:

natural sediment

Limit test:

no

Exposure duration

Duration:

49 d

Exposure phase:

total exposure duration

Post exposure observation period:

none

Test conditions

Hardness:

no data

Test temperature:

15°C

pH:

8.03

Dissolved oxygen:

5.1 mg/L (overlaying water)

Salinity:

34 g/L

Ammonia:

0.37 mg/L

Nominal and measured concentrations:

Measured total sulfides in sediment pore water at the start of testing: 0.1-19.2-52.4-88.1 mg S2-/L
Measured total sulfides in sediment pore water at the end of testing: 0.5-16.6-46.2-83.7 mg S2-/L
Mean H2S (calculated): 0.034-1.1-3.1-5.7 mg H2S/L

Details on test conditions:

TEST SYSTEM
- Test container (material, size): aquaria of 7-mm clear plexiglass (24x15.5 cm)
- Sediment volume: 4 cm thick
- Aeration: only the clean seawater flowing above the sediment layer was aerated
- A sodium sulfide solution was pumped to the sub-sediment reservoir of each aquarium, where it diffused up through the sediment layer. Clean seawater flowed (18 mL/min) above the sediment layer.
- Systems were allowed to equilibrate for at least 60 days

EXPOSURE REGIME
- No. of organisms per container (treatment): 15
- No. of replicates per treatment group: 3
- No. of replicates per control: 3
- Feeding regime: no data
- Type and preparation of food: no data
- Amount of food: no data

RENEWAL OF OVERLYING WATER
- Details on volume additions: 0.5 mL/min (sulfide solution), i.e., renewal every 2-3 days
- Flow-rate: 18 mL/min (overlying water)

OVERLYING WATER CHARACTERISTCS
- Type of water: seawater
- For seawater characterization see above

SOURCE OF NATURAL SEDIMENT
- Location and description of sampling site: Newport Bay
- Contamination history of site: clean, natural sediment was used

CHARACTERIZATION OF (ARTIFICIAL; delete if not applicable) SEDIMENT
- Particle size distribution
- % sand: 96.5%
- % silt: 2%
- % clay: 1.5%
- Further constituents
- Total organic carbon: 0.11%

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): survival, growth (test diameter and wet weight), and male and female gonad production (wet weight)

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

49 d

Dose descriptor:

NOEC

Effect conc.:

1.1 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

other: H2S

Basis for effect:

mortality

Effect concentrations 2

Duration:

49 d

Dose descriptor:

LOEC

Effect conc.:

3.1 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

other: H2S

Basis for effect:

mortality

Effect concentrations 3

Duration:

49 d

Dose descriptor:

NOEC

Effect conc.:

3.1 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

other: H2S

Basis for effect:

other: growth (test diameter)

Effect concentrations 4

Duration:

49 d

Dose descriptor:

LOEC

Effect conc.:

5.7 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

other: H2S

Basis for effect:

other: growth (test diameter)

Effect concentrations 5

Duration:

49 d

Dose descriptor:

NOEC

Effect conc.:

< 1.1 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

other: H2S

Basis for effect:

other: growth (wet weight)

Effect concentrations 6

Duration:

49 d

Dose descriptor:

LOEC

Effect conc.:

1.1 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

other: H2S

Basis for effect:

other: growth (wet weight)

Effect concentrations 7

Duration:

49 d

Dose descriptor:

NOEC

Effect conc.:

3.1 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

other: H2S

Basis for effect:

other: female gonad production (wet weight)

Effect concentrations 8

Duration:

49 d

Dose descriptor:

LOEC

Effect conc.:

5.7 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

other: H2S

Basis for effect:

other: female gonad production (wet weight)

Effect concentrations 9

Duration:

49 d

Dose descriptor:

NOEC

Effect conc.:

< 1.1 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

other: H2S

Basis for effect:

other: male gonad production (wet weight)

Effect concentrations 10

Duration:

49 d

Dose descriptor:

LOEC

Effect conc.:

1.1 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

other: H2S

Basis for effect:

other: male gonad production (wet weight)

Reported statistics and error estimates:

Significant effects were identified using nested ANOVAs tested pairwise against the controls.

Applicant's summary and conclusion

Conclusions:

In this test, the sea urchin Lytechinus pictus was exposed to H2S for 49 days by pumping sodium sulfide solutions through the sediment in a flow-through system. The most critical (not-unbound) NOEC was observed for survival and was 1.1 mg H2S/L.