Administrative data

Purpose flag:
key study
Study result type:
read-across from supporting substance (structural analogue or surrogate)
Study period:
no specified
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
Not conducted to GLP and lacking analysis certificate for test chemical. Standard EPA procedures were followed and chemical analysis was conducted. 

Iuclid 4 rationale:
Test performed according to standardized EPA guideline for
testing of effluents, with determination of test concentrations. Test parameters pH and 
oxygen measured but 
not all reported. No information about survival in controls.
Replicate test performance.

Data source

Reference
Reference Type:
publication
Title:
Statistical models to predict the toxicity of major ions to Ceriodaphnia dubia, Daphnia magna and Pimephales promelas (Fathead minnows)
Author:
Mount, D.R., Gulley, D.D., Hockett, J.R., Garrison, T.D., Evans, J.M.
Year:
1997
Bibliographic source:
Environ. Toxicol. Chem.16(10):2009-2019.

Materials and methods

Principles of method if other than guideline:
Toxicity tests followed the general guidance of the U.S. Environmental Protection Agency (USEPA) this test was based on EPA/600/4-90/027 (1991)
GLP compliance:
no

Test materials

Identity of test material same as for substance defined in section 1 (if not read-across):
no
Test material identityopen allclose all
Identifier:
EC name
Identity:
sodium sulphate
Details on test material:
Test substances were all of reagent grade or higher supplied by Sigma Aldrich

Sodium Sulphate
Analytical monitoring:
yes
Details on test solutions:
96-hours static test in reconstituted water. 

Test organisms

Test organisms (species):
Pimephales promelas
Details on test organisms:
All organisms used in testing were obtained from in-house cultures (ENSR, Fort Collins, CO. USA);Fathead minnow brood stock were
cultured at 20 to 25°C in tap water that was pretreated with activated carhon. Eggs and larva were held in MHRW; larva were fed brine shrimp naupli
(Artemia) twice daily until they were used in testing.

Study design

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
96 h
Post exposure observation period:
-

Test conditions

Hardness:
Moderately Hard Reconstituted Water. (MHRW)
Test temperature:
fathead minnows were tested at 25°C
pH:
Measured pH varied according to the components of the solution but was generally between pH 7.5 and 9.0
Dissolved oxygen:
DO was measured with a Yellow Springs instrument model 54 DO meter.
Nominal and measured concentrations:
All ion concentrations measured in the stock solutions were compared to nominal values. If the measured concentrations differed from the nominal 
value by more than 20% the actual measured concentrations were substituted for the nominal concentratlons. The actual concentrations tested were not individually reported.
Details on test conditions:
For fathead minnow tests, 100 µl of concentrated brine shrimp nauplii was added after 48 h of exposure. Though solutions were not subsequently 
renewed as recommended by the USEPA. Analysis confirmed however that the substance concentrations remained stable.
Reference substance (positive control):
yes
Remarks:
NaCl

Results and discussion

Effect concentrationsopen allclose all
Duration:
96 h
Endpoint:
LC50
Effect conc.:
7 960 mg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
test mat.
Basis for effect:
mortality
Duration:
24 h
Endpoint:
LC50
Effect conc.:
> 8 080 mg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
test mat.
Basis for effect:
mortality
Duration:
48 h
Endpoint:
LC50
Effect conc.:
> 7 960 mg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
test mat.
Basis for effect:
mortality
Details on results:
Additional observations were not reported as this paper is a composition of many test results for different test chemicals. However it can be 
concluded from these results that sodium sulphate is non toxic to fish.
Results with reference substance (positive control):
During the tests that were conducted reference tests with NaCl were conducted to account for any drift in sensitivity that may have occured
Reported statistics and error estimates:
LC50 concentrations were also calculated using a computer program following the trimmed Spearman-Karber method.

Applicant's summary and conclusion

Conclusions:
Study conducted to EPA guidelines, with analysis. Although lacking detail expected of a substance specific report this study can be considered
reliable with restrictions. Sodium sulfate can be considered not to be toxic to fish.
Executive summary:
Although lacking detailed descriptions of methods, GLP accreditation and analysis certificates, EPA guidelines were followed article was published in setac press and chemical analysis was conducted. Can be considered reliable with restrictions.
Validity criteria fulfilled:
yes