Methyl 2-naphthyl ether

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Remarks:

experimental data of target chemical and read across substances

Justification for type of information:

Experimental test result performed by following guidelines similar to standard OECD 203 guidleines.

Reason / purpose:

other: Target chemical

Reason / purpose:

read-across source

Reason / purpose:

read-across source

Qualifier:

equivalent or similar to

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

WoE3: The test concentrations selected for the study were 0, 3.125 mg/L, 6.25 mg/L,12.5 mg/L, 25 mg/L, 50 mg/L.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

WoE2:
TEST ORGANISM
- Common name:Zebra Fish

WoE3:
TEST ORGANISM
- Common name:Zebra Fish
- Length at study initiation (length definition, mean, range and SD): average 1.86 cm
- Weight at study initiation (mean and range, SD): average 0.084 g
- Housing:The fishes were kept in a static tank in tap water passed through reverse osmosis system, under natural conditions along with proper feed and aeration.
- Duration of housing: 15 days
- Photoperiod: 16 hour light and 8 hour darkness
- Diet : Standard brand feed, once daily
- Acclimatization: seven days
- Feeding frequency: Once in a day

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

WoE3: 152.5 mg of CaCO3

Test temperature:

WoE3: 23.8 °C

pH:

WoE3: 7.1

Dissolved oxygen:

WoE3: 7 mg/l

Nominal and measured concentrations:

WoE3:Nominal concentration 0, 3.125 mg/L, 6.25 mg/L,12.5 mg/L, 25 mg/L, 50 mg/L.

Details on test conditions:

WoE3:
TEST SYSTEM
- Test vessel: Plastic aquaria
- Material, size, headspace, fill volume: 5 liters of plastiic aquaria filled with 2 liter of water
- Aeration: Aeration in test vessels was provided 1 day before the start of experiment
- No. of organisms per vessel: 8 fishes

OTHER TEST CONDITIONS
- Photoperiod: 16 hour light and 8 hour darkness

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

21.4 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

50 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

28 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Validity criteria fulfilled:

yes

Conclusions:

Based on various data obtained from different sources, the median lethal concentration LC50 of test chemcial to fresh water fish was in the range of 21.4 to 50mg/L.

Executive summary:

Data available for target chemical and structurally & functionally similar read across analogues, has been reviewed to determine the effect caused on fresh water fishes. The studies are summarised below:

In a prediction done using the OECD QSAR toolbox version 3.4, the short term toxicity on fish was predicted for test chemical for 96 hr. EC50 value was estimated to be 21.4 mg/l on Danio rerio (Zebra fish) for 96 h duration.

Another short term toxicity to fish study was conducted for 96 hrs for assessing the effect of test chemical on Zebra fish (Danio rerio). The test was performed in accordance to OECD guideline No. 203 “Fish Acute Toxicity Test”. Zebra fish (Danio rerio) of average weight 0.084 g and average length of 1.86 cm was used as a test organism for the study. Test fishes were kept in a static tank in tap water passed through reverse osmosis system, under natural conditions along with proper feed and aeration. During the housing period, test fishes were fed once daily with standard brand fed. The test conditions during the housing of the test organisms were oxygen content of 7.0 mg/l, pH 7.4, water temperature 23.8°C and under a photoperiod of 16:8 hr light: dark conditions, respectively. Nominal test chemical conc. used for the study were 0, 3.125 mg/L, 6.25 mg/L,12.5 mg/L, 25 mg/L, 50 mg/L, respectively. Total 48 fishes were exposed to test chemical in a 5 lit bowl aquaria containing 4 liters of potable water. The test vessels were placed in a room at a temperature of 23.8°C, pH 7.1, hardness of water 152.5 mg of CaCO3 and under a photoperiod of 16:8 hr light: dark conditions, respectively. Aeration in test vessels was provided 1 day before the start of the experiment. The fishes were moving slowly in the test chemical conc. as compared to the control. No mortalities were observed in the control vessel. On the basis of effect of test chemical on the mortality of test organism, the median lethal concentration (LC50 (96 h)) value was determined to be 50 mg/l.

For the test chemical, short term fish toxicity study was conducted for 96 hrs for assessing the effect of test chemical. Study was performed in a static fresh water system. On the basis of effect of test chemical on the mortality of the test organism fish, the 96 hrs LC50 value was determined to be 28 mg/l.

On the basis of the predicted data & various experimental studies of the test chemicals and applying the weight of evidence approach, the LC50 value of the test chemical on test organism fish can be expected to be in the range of 21.4 to 50 mg/L, respectively. Thus, based on the LC50 value, test chemical can be considered as toxic to fish and considered to be classified in ‘aquatic chronic category 3’ as per CLP classification criteria.

Description of key information

Based on various data obtained from different sources, the median lethal concentration LC50 of test chemcial to fresh water fish was in the range of 21.4 to 50mg/L.

Key value for chemical safety assessment

LC50 for freshwater fish:

50 mg/L

Additional information

Data available for target chemical and structurally & functionally similar read across analogues, has been reviewed to determine the effect caused on fresh water fishes. The studies are summarised below:

In a prediction done using the OECD QSAR toolbox version 3.4, the short term toxicity on fish was predicted for test chemical for 96 hr. EC50 value was estimated to be 21.4 mg/l on Danio rerio (Zebra fish) for 96 h duration.

Another short term toxicity to fish study was conducted for 96 hrs for assessing the effect of test chemical on Zebra fish (Danio rerio). The test was performed in accordance to OECD guideline No. 203 “Fish Acute Toxicity Test”. Zebra fish (Danio rerio) of average weight 0.084 g and average length of 1.86 cm was used as a test organism for the study. Test fishes were kept in a static tank in tap water passed through reverse osmosis system, under natural conditions along with proper feed and aeration. During the housing period, test fishes were fed once daily with standard brand fed. The test conditions during the housing of the test organisms were oxygen content of 7.0 mg/l, pH 7.4, water temperature 23.8°C and under a photoperiod of 16:8 hr light: dark conditions, respectively. Nominal test chemical conc. used for the study were 0, 3.125 mg/L, 6.25 mg/L,12.5 mg/L, 25 mg/L, 50 mg/L, respectively. Total 48 fishes were exposed to test chemical in a 5 lit bowl aquaria containing 4 liters of potable water. The test vessels were placed in a room at a temperature of 23.8°C, pH 7.1, hardness of water 152.5 mg of CaCO3 and under a photoperiod of 16:8 hr light: dark conditions, respectively. Aeration in test vessels was provided 1 day before the start of the experiment. The fishes were moving slowly in the test chemical conc. as compared to the control. No mortalities were observed in the control vessel. On the basis of effect of test chemical on the mortality of test organism, the median lethal concentration (LC50 (96 h)) value was determined to be 50 mg/l.

For the test chemical, short term fish toxicity study was conducted for 96 hrs for assessing the effect of test chemical. Study was performed in a static fresh water system. On the basis of effect of test chemical on the mortality of the test organism fish, the 96 hrs LC50 value was determined to be 28 mg/l.

On the basis of the predicted data & various experimental studies of the test chemicals and applying the weight of evidence approach, the LC50 value of the test chemical on test organism fish can be expected to be in the range of 21.4 to 50 mg/L, respectively. Thus, based on the LC50 value, test chemical can be considered as toxic to fish and considered to be classified in ‘aquatic chronic category 3’ as per CLP classification criteria.