Benzenesulfonic acid, mono-C16-24-alkyl derivs., calcium salts , overbased including distillates (petroleum), hydrotreated heavy paraffinic C10-C50

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study meets the criteria for Klimisch code 1 because it followed an internationally recognised method (EPA OTS 797.1300) and was carried out to Good Laboratory Practice.

Qualifier:

according to guideline

Guideline:

EPA OTS 797.1300 (Aquatic Invertebrate Acute Toxicity Test, Freshwater Daphnids)

Deviations:

no

Remarks:

None reported

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

Total organic carbon (TOC) measurements of initial (0 hours) test solutions and at test termination (48 hours).

Vehicle:

no

Details on test solutions:

The 100, 300 and 1000 mg/L nominal loadings were prepared using sterilised filtered well water. Individual water accommodation fractions were prepared by stirring the vessel for 24 hours with a Teflon coated magnetic stir bar and removing the water phase for the toxicity test.

Dilution water was filtered well water collected at Hampton, New Hamshire. Water was adjusted to a hardness of 176 mg/L, passed through activated carbon and then an ultraviolet steriliser. Water was stored in a polyethylene tank where it was aerated.

No undissolved test material was reported on the surface of the test vessels during the entire toxicity test.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Waterflea
- Source: In-house laboratory culture
- Age at study initiation (mean and range, SD): Juvenile (<24 hours old)

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

Not reported

Hardness:

176 mg CaCO3/L

Test temperature:

20.4 to 20.9°C

pH:

7.2 to 8.1

Dissolved oxygen:

7.9 to 8.7mg/L

Salinity:

Not relevant

Nominal and measured concentrations:

Control, 100, 300 and 1000 mg/L WAF.

TOC levels were 2.8-3.5 mg/L in the control, 2.8-3.6 mg/L at 100 mg/L WAF, 3.0-3.7 mg/L at 300 mg/L WAF and 2.7-3.4 mg/L at 1000 mg/L WAF loading. TOC levels were not considered to be indicative of actual test material concentrations and results are therefore based on nominal loading rates.

Details on test conditions:

TEST SYSTEM
- Test vessel: 250 mL glass beaker containing 200 mL of test solution, loosely covered to reduce the entry of dust
- No. of organisms per vessel: Ten
- No. of vessels per concentration (replicates): Two

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Filtered well water collected at Hampton, New Hampshire
- Total organic carbon: 2 mg/L
- Alkalinity: pH 7.2 to 8.1
- Conductivity: 860 to 880 µmhos/cm

OTHER TEST CONDITIONS
- Photoperiod: 16-hours light per day
- Light intensity: 20 µEin/m²

EFFECT PARAMETERS MEASURED: Immobilisation

TEST CONCENTRATIONS
- Test concentrations: Control, 100, 300 and 1000 mg/L nomial WAF

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

other: WAF loading rate

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

other: WAF loading rate

Basis for effect:

mobility

Details on results:

Control immobilisation did not exceed the test validity criterion (i.e. <10% immobilisation in the controls).

At 24-hours, no immobilised or dead organisms were observed in the control or treatments. At 48-hours, 5, 0, 20 and 5% immobilisation were reported for control, 100, 300 and 1000 mg/L, respectively.

Reported statistics and error estimates:

The statistical analysis of survival data is not warranted.

Validity criteria fulfilled:

yes

Conclusions:

The test substance was not toxic to daphnids at loading rates up to 1000 mg/L and the EC50 is considered to be >1000mg/l.

Executive summary:

The 48–hour acute toxicity of benzenesulphonic acid, C14-24 branched / linear alkyl derivative, calcium salt to Waterfleas (Daphnia magna) was studied under static conditions. Daphnids were exposed to control and test chemical at nominal concentrations of 100, 300 and 1000 mg/L WAF for 48 hours.  Mortality/immobilisation and sublethal effects were observed daily.

 

This study is classified as acceptable and satisfies the guideline requirements for an acute toxicity study with freshwater invertebrates.

 

Results Synopsis

 

Test Organism Age: Neonates (<24 hours old)

Test Type: Static

Percent survival/unaffected organisms was 95% in the control, 100% at 100 mg/l, 80% at 300 mg/l and 95% at 1000 mg/l.

48 hour Effective Loading Rate (EL50) = >1000 mg/L

Description of key information

The toxcity of the substance has been measured experimentally with freshwater Daphnia.  Due to the extremely low water solubility all studies have been conducted using Water Accomodated Fractions and completed as limit tests.  

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

1 000 mg/L

Additional information

The EC50 in freshwater Daphnia is considered to be >1000 mg/l. The substance is, therefore, considered not toxic to Daphnia magna. Nevertheless, adequate controls will be in place during production and use to ensure that the substance is not released to the environment.

The toxicity of the substance has not been assessed using marine invertebrate species, but it is considered likely to be similar to freshwater species.