Diarsenic trioxide

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

equivalent or similar to guideline

Guideline:

other: American Society for Testing and Materials (ASTM), 1980 Standard practice for conducting acute toxicity tests with fishes, macroinvertebrates and amphibians. E729-80

Qualifier:

equivalent or similar to guideline

Guideline:

other: American Public Health Association, American Water Works Association and Water Pollution Control Federation. 1985. Standard methods for the Examination of Water and Waste Water, 16th. ed.

Qualifier:

equivalent or similar to guideline

Guideline:

other: US. Environmental Protection Agency. 1979. Methods for chemical analysis of water and wastes. EPA 600-479-020. Environmental Monitoring and Support Laboratory, Office of Research and Development

Principles of method if other than guideline:

The acute effect of arsenic on fathead minnows (Pimephales promelas) was tested in a 96 h toxicity test conducted in Lake Superior water.

GLP compliance:

not specified

Specific details on test material used for the study:

reported in study: regent grade sodium arsenite (Na2AsO4.7H2O)

Analytical monitoring:

yes

Details on sampling:

Not specified.

Vehicle:

no

Details on test solutions:

A stock solution was prepared by dissolving reagent-grade sodium arsenite (Na2AsO4 · 7 H2O) in distilled water.

Test organisms (species):

Pimephales promelas

Details on test organisms:

TEST ORGANISM
- Common name: fathead minnow
- Source: Laboratory culture
- Age at study initiation (mean): 30 d
- Weight at study initiation (mean): 0.15 g

ACCLIMATION
- Acclimation period: not specified
- Acclimation conditions: same as test
- Type and amount of food during acclimation: not specified

FEEDING DURING TEST
- Not specified

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

4 d

Hardness:

43.9 ± 1.0 mg/L CaCO3

Test temperature:

25 ± 3 °C

pH:

7.4 (6.0-8.1)

Dissolved oxygen:

at least 70 % saturation

Conductivity:

91 ± 1.4 µmhos

Nominal and measured concentrations:

Five concentrations at a 0.5 dilution factor and a control (Concentrations not further specified). Test concentrations were analytically confirmed.

Details on test conditions:

TEST SYSTEM
- Test vessel: glass test chamber (size: 7 cm * 18 cm * 9 cm (w*l*h); water depth: 6.4-7.0 cm
- Type of flow-through: FMI pumps (Fluid Metering Inc., Oyster Bay NY)
- Renewal rate of test solution (flow rate): 15 ± 1 ml/min
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2
- Biomass loading rate: ca. 1.7 g/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Lake Superior water filtered through sand and heated to 25 ± 3 °C
- Total organic carbon: 2.0 ± 1.4 mg/L
- Alkalinity: 42.2 ± 1.9 mg/L as CaCO3

OTHER TEST CONDITIONS
- Photoperiod: 16:8 h light:dark
- Light intensity: 110-320 lux

EFFECT PARAMETERS MEASURED :
- mortality, at 96 h

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

12.6 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

element (dissolved fraction)

Remarks:

As

Basis for effect:

mortality (fish)

Remarks on result:

other: CL: 9.90-15.90 mg/L

Reported statistics and error estimates:

96 h LC50 values were determined with a computerized, modified trimmed Spearman-Karber method. Mortality data from replicate exposure tanks were combined before LC50 values were calculated.

Validity criteria fulfilled:

not specified

Remarks:

Control mortality not reported; Dissolved oxgen level ok

Conclusions:

The 4-d LC50 for mortality of the fish Pimephales promelas is 12.6 mg As/L (measured), and this LC50 value is considered for the Chemicals Safety Assessment.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

equivalent or similar to guideline

Guideline:

other: American Society for Testing Materials (ASTM), 1988 Standard guide for conducting early life-stage toxicity tests with fishes. E 1241-88. West Conshohocken, PA: ASTM.

Qualifier:

equivalent or similar to guideline

Guideline:

other: US EPA, 1975 Methods for the acute toxicity tests with fish, macroinvertebrates and amphibians. The Committee on Methods for Toxicity Tests with Aquatic Organisms, Ecological Research Series EPA-660-75-009.

GLP compliance:

not specified

Analytical monitoring:

yes

Details on sampling:

- Sampling method: 200 ml pooled samples (100 ml from each test chamber) were analyzed from the high, medium, low, and control concentration waters.
- Sample storage conditions before analysis: at 4 °C

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- test solutions were prepared in 22-g/L salt water (Instant Ocean)

Test organisms (species):

Morone saxatilis

Details on test organisms:

TEST ORGANISM
- Common name: Striped bass
- Source: Central Valley Fish Hatchery, California Department od Fish and Game
- Weight at study initiation (mean): 1.8 g

ACCLIMATION
- Acclimation period: 48 h
- Acclimation conditions: same as test

FEEDING DURING TEST
- None

Test type:

static

Water media type:

saltwater

Limit test:

no

Total exposure duration:

4 d

Hardness:

4.43 g/L CaCO3

Test temperature:

20 °C

pH:

8.12

Salinity:

22.5 g/L

Conductivity:

36.25 µmho/cm (at 25 °C)

Nominal and measured concentrations:

Highest concentration 100 mg/L, tested in a 60% serial dilution. Test concentrations were analytically confirmed (102–104% of nominal).

Details on test conditions:

TEST SYSTEM
- Test vessel: 19.6 L glass test chambers
- Fill volume: 15 L
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2
- Biomass loading rate: 0.6 g/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Instant Ocean
- Alkalinity: 88 mg/L as CaCO3

OTHER TEST CONDITIONS
- Photoperiod/Light intensity: Ambient light

EFFECT PARAMETERS MEASURED:
- mortality, every 24 h

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

10.3 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

element (dissolved fraction)

Remarks:

As

Basis for effect:

mortality (fish)

Details on results:

Test concentrations were analytically confirmed (102–104% of nominal).

Reported statistics and error estimates:

Probit analysis was used for calculation of 96-h LC50 values. The 95 % confidence interval was calclulated.

Validity criteria fulfilled:

yes

Conclusions:

In an acute toxicity test with the saltwater fish Morone Saxatilis (striped bass), following standard test guidelines ASTM E 1241-88 (1988) and US EPA 660-75-009 (1975), a 4-d LC50 of 10.3 mg As/L (nominal) was determined for the mortality of Morone saxatilis.

Description of key information

Eight reliable data points were identified for acute toxicity of As to fish, representing five different standard freshwater fish species (Danio rerio, Jordanella floridae, Oncorhynchus mykiss, Pimephales promelas and Poecilia reticulata). 96 -h LC₅₀values range between 12600 µg As/L and 29980 µg As/L The lowest reliable acute value is a 96h-LC₅₀of 12600 µg As/L for the fish P. promelas. This value is put forward for classification purposes. In addition, one reliable datapoint was identified for a marine fish (Morone saxatilis) with a reported 96-h LC₅₀value of 10300 µg As/L.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

12.6 mg/L

Marine water fish

Marine water fish

Effect concentration:

10.3 mg/L