β-bromostyrene

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

calculation (if not (Q)SAR)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

accepted calculation method

Justification for type of information:

Data is from computational model developed by USEPA

Qualifier:

according to guideline

Guideline:

other: Modelling database

Principles of method if other than guideline:

Short term toxicity of test chemical were studied on the mortality of fish.

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

other: Fish

Test type:

static

Water media type:

freshwater

Total exposure duration:

96 h

Test temperature:

25 Deg.C

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

13.842 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: ECOSAR Class:Neutral Organics

Validity criteria fulfilled:

no

Conclusions:

Based on the EPI Suite ECOSAR version prediction model, the 96 hours LC50 was estimated to be 13.842 mg/l on Fish for test substance on the basis of mortality effects.

Executive summary:

Using the EPI Suite ECOSAR version, the short term toxicity on fish was predicted for test substance on the basis of effects observed in a static freshwater system. The lethal concentration LC50 value for the substance was estimated to be 13.842 mg/l for fish for 96 hr duration. Based on this value it can be concluded that the substance can be considered to be toxic to aquatic environment and can be classified in aquatic chronic category 3 as per the CLP classification criteria. But as the chemical was readily biodegradable in water, thus on that criteria chemical consider to be nontoxic and not classified as per the CLP classification criteria.

Description of key information

Using the EPI Suite ECOSAR version, the short term toxicity on fish was predicted for test substance on the basis of effects observed in a static freshwater system. The lethal concentration LC50 value for the substance was estimated to be 13.842 mg/l for fish for 96 hr duration. Based on this value it can be concluded that the substance can be considered to be toxic to aquatic environment and can be classified in aquatic chronic category 3 as per the CLP classification criteria. But as the chemical was readily biodegradable in water, thus on that criteria chemical consider to be nontoxic and not classified as per the CLP classification criteria.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

13.842 mg/L

Additional information

Various experimental studies and predicted data available for the test chemical and structually and functionally similar read across chemicals were reviewed to determine the toxic nature of test chemical on the growth and other activity of microorganisms. The studies are as mentioned below:

 

In the first data using the EPI Suite ECOSAR version, the short term toxicity on fish was predicted for test substance on the basis of effects observed in a static freshwater system. The lethal concentration LC50 value for the substance was estimated to be 13.842 mg/l for fish for 96 hr duration. Based on this value it can be concluded that the substance can be considered to be toxic to aquatic environment and can be classified in aquatic chronic category 3 as per the CLP classification criteria. But as the chemical was readily biodegradable in water, thus on that criteria chemical consider to be nontoxic and not classified as per the CLP classification criteria.

Similar prediction done using average value of both models i.e Leadscope and SciMatics SciQSAR model and the result were predicted in Battery model. Based on the QSAR prediction done using the Danish (Q)SAR Database, the 96 hours LC50 was estimated to be 4.41 mg/l on Pimephales promelas for test substance with mortality effects. Thus based on this readily biodegradability of test chemical, it can be concluded that the substance cannot be classified as toxic as per the criteria of CLP regulation.

Above predicted data was supported by the experimental data. This study outlines the effects of the test chemical on the mortality rate of the zebrafish at an exposure period of 96 hours. Test chemical was dissolved in the synthetic fresh water and fishes were exposed to test chemical in semi static condition. Where the chemical was renewed after every 24 hours till 4 days. Nominal concentrations were selected to treat the fishes with test chemical, based on the mortality observation, LC0 and LC100 was determined as 1.41 mg/L and 3.93 mg/L for 24 hrs, respectively. The geometric mean of LC0 and LC100 was observed to be 2.95 mg/L (24hr). Since the test substance is readily biodegradable and BCF is <500, it can be nontoxic to aquatic environment, and cannot be classified.

The fourth study was designed to assess the toxic effects of the test compound on the Oncorhynchus mykiss (Rainbow  trout) in a 24 hr study period. Test conducted under the static system for 24 hrs. The no observed effect concentration (NOEC) value of test chemical on fish [Oncorhynchus mykiss] in a 24 hr study was determine to be 5 mg/L. Thus chemical consider to be nontoxic.

In the fifth 96 hrs short term toxicity study was conducted on BluegillLepomis macrochirusfor the test compound. Concentration selected for the study was 1.97 mg/L.

Since no mortality was noted, the No Observed Effect Concentration (NOEC) for the test compound is reported as 1.97 mg/L. Since the substance test compound is readily biodegradable and also BCF is less than 500 thus it can be considered as not toxic to aquatic environment and cannot be classified as per the new CLP guidelines.

Thus based on the above all data and results, chemical consider to be nontoxic and not classified as per the CLP classification criteria.