3,7-dimethyl-1-octyl acetate

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

Qualifier:

according to guideline

Guideline:

other: as mentioned below

Principles of method if other than guideline:

Estimation 96 hrs LC50 value of test chemical on Fathead minnow by Danish QSAR database.

GLP compliance:

not specified

Analytical monitoring:

not specified

Vehicle:

not specified

Test organisms (species):

other: Fathead minnow

Test type:

static

Water media type:

freshwater

Total exposure duration:

96 h

Reference substance (positive control):

not specified

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

2.33 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Sublethal observations / clinical signs:

Table: Table showing the Fathead minnow 96 hr LC50 values estimated by two different models i.e, Leadscope and SciQSAR & the average LC50 value was given by the third model i.e, Battery model.

 

DK	Battery	Leadscope	SciQSAR
Fathead minnow96 hr LC50 (mg/l)	2.33176	2.546504	2.117017
Domain	IN	IN	IN

 

Where,

IN = inside applicability domain

Validity criteria fulfilled:

not specified

Conclusions:

Based on effect of test chemical on the mortality of the test organism Fathead minnow, the 96 hrs LC50 by three different model i.e, Battery, Leadscope and SciQSAR used within Danish QSAR database was estimated to be 2.33 mg/l.

Executive summary:

Estimated 96 hrs LC50 value of test chemical on the test organism Fathead minnow was evaluated by three different models i.e, Battery, Leadscope and SciQSAR used within Danish QSAR database. On the basis of effect of test chemical on the mortality of the test organism Fathead minnow, the 96 hrs LC50 was estimated to be 2.33 mg/l.Thus, based on the LC50 value, chemical can be considered as toxic to aquatic organisms. Since the test chemical is readily biodegradable in water, test chemical can be considered as non-toxic to aq. organisms and thus can be considered to be not classified as per CLP classification criteria.

Description of key information

Estimated 96 hrs LC50 value of test chemical on the test organism Fathead minnow was evaluated by three different models i.e, Battery, Leadscope and SciQSAR used within Danish QSAR database (2017). On the basis of effect of test chemical on the mortality of the test organism Fathead minnow, the 96 hrs LC50 was estimated to be 2.33 mg/l.Thus, based on the LC50 value, chemical can be considered as toxic to aquatic organisms. Since the test chemical is readily biodegradable in water, test chemical can be considered as non-toxic to aq. organisms and thus can be considered to be not classified as per CLP classification criteria.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

2.33 mg/L

Additional information

Predicted data of the test chemical and various supporting weight of evidence studies for its structurally similar read across chemical were reviewed for the short term toxicity to fish end point which are summarized as below:

 

In a prediction done usingthree different models i.e, Battery, Leadscope and SciQSAR used within Danish QSAR database(2017), theEstimated 96 hrs LC50 value of test chemical on the test organism Fathead minnow was evaluated. On the basis of effect of test chemical on the mortality of the test organism Fathead minnow, the 96 hrs LC50 was estimated to be 2.33 mg/l.

 

In a supporting weight of evidence study from authoritative database (J-CHECK, 2018),an acute toxicity test was conducted for 96 hrs for assessing the effect of test chemical on Oryzias latipes (Japanese rice fish). The test was performed in accordance to OECD guideline No. 203“Fish Acute Toxicity Test”. Oryzias latipes (Japanese rice fish) was used as a test organism for the study. Test chemical conc. used for the study were 35.0, 26.9, 20.7, 15.9, 12.3 mg/L (geometric ratio1.3), control. Analytical monitoring involve the use of HS-GC. Study was performed using 10 per conc. (5 per vessel) Oryzias latipes in a semi-static fresh water system. Total 50 fishes were exposed to test chemical in a closed vessel. The test vessels were placed under a photoperiod of room light, 16:8 hr light: dark conditions, respectively. On the basis of mortality of the test organism Oryzias latipes (Japanese rice fish), the 96 hrs LC50 value was determined to be 16.6 mg/l (95% C. I. – 12.3 to 23.8 mg/l), respectively. 

 

For the test chemical, Short term toxicity to fish study was carried out for 96 hrs (Handbook, 2009). The study was based on the effects of the test chemical on Pimephales promelas in a static fresh water system. Pimephales promelas (Fathead minnow) was used as a test organism. On the basis of mortality of the test organism Pimephales promelas, the 96 hr LC50 was determined to be 18 mg/l.

 

On the basis of the above results, it can be concluded that the test chemical can be considered astoxic to fish. Since the test chemical is readily biodegradable in water, test chemical can be considered as non-toxic to fish and thus can be considered to be not classified as per CLP classification criteria.