Benzyl methacrylate

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1984

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Remarks:

Well documented publication. No GLP.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material (as cited in study report): Benzyl methacrylate

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0 (control), 3.54, 5.45, 8.38, 12.9 and 19.9 mg/L
- Sampling method: sampling at mid-depth at 0, 24, 48, 72 and 96 h
- Sample storage conditions before analysis: immediate analysis or adequate preservation for later analysis

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: diluted from stock (32 mg/L)
- Controls: water without test substance
- Evidence of undissolved material (e.g. precipitate, surface film, etc): no data

Test organisms (species):

Pimephales promelas

Details on test organisms:

- Common name: Fathead minnow
- Strain: no data
- Source: cultured at U.S. EPA Environmental Research Laboratory-Duluth
- Age at study initiation: 29 days
- Length at study initiation: 17.5 ± 2.038 mm
- Weight at study initiation: 0.071 ± 0.0271 g
- Loading 1.420 g/L
- Feeding during test: no feeding during test, last feeding 24 h before test

ACCLIMATION
- Acclimation period: no data
- Acclimation conditions (same as test or not):
- Type and amount of food: larvae were fed brine shrimp nauplii in excess, adults were fed with frozen adult brine shrimp
- Feeding frequency: twice daily, on weekend days once daily

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

no data

Hardness:

45.6 ± 0.25 mg/L CaCO3

Test temperature:

24.6 ± 0.9°C

pH:

7.70 ± 0.06

Dissolved oxygen:

7.4 ± 0.28 mg/L

Nominal and measured concentrations:

nominal (measured, mean)
0 (0.3) mg/L
3.54 (3.02) mg/L
5.45 (4.54) mg/L
8.38 (7.03) mg/L
12.9 (11.2) mg/L
19.9 (17.1) mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: no data
- Material, size, headspace, fill volume: 1 L tank volume
- Aeration: no data
- Renewal rate of test solution (frequency/flow rate): 14.4 chamber volumes/day
- No. of organisms per vessel: 20 fish per concentration/control
- Biomass loading rate: no data

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: lake superior water, filtered through sand and cotton fibre flter
- Total organic carbon: no data
- Particulate matter: no data
- Metals: <167.5 µg/L (Al, Cd, Cr, Co, Cu, Fe, Pb, Mn, Ni, Zn)
- Pesticides: no data
- Chlorine: 1.2 – 1.3 mg/L
- Alkalinity: no data
- Ca/Mg ratio: ca. 4
- Conductivity: 78 – 86 µmhos/cm
- Culture medium different from test medium: no
- Intervals of water quality measurement: no data

OTHER TEST CONDITIONS
- Adjustment of pH:
- Photoperiod: 16 h
- Light intensity: no data

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
mortality, body morphology, general activity, locomotor activity, schooling behaviour, pigmentation were recorded at 20, 24, 48, 51.5, 72, 96 h

TEST CONCENTRATIONS
- Spacing factor for test concentrations: ca. 1.5 (concentrations tested: 3.43, 5.45, 8.38, 12.9 and 19.9 mg/L)
- Justification for using less concentrations than requested by guideline: 5 concentrations were used
- Range finding study: no data

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

4.67 mg/L

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Remarks on result:

other: LC50: (95% C.I. 4.25 - 5.13 mg a.i./L)   

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

4.48 mg/L

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Remarks on result:

other: EC50: (95% C.I. 4.25 - 5.13 mg a.i./L)

Details on results:

- Behavioural abnormalities: at 5.45 mg/L and higher loss of schooling behaviour, hypoactivity, loss of equilibrium prior to death
- Observations on body length and weight: no data
- Mortality of control: none
- Other adverse effects control: none

Results with reference substance (positive control):

no reference substance tested

Reported statistics and error estimates:

LC50 and corresponding 95% confidence interval was calculated using corrected avarage of the measured concentrations and the Trimmed Speraman-Karber Method.

Validity criteria fulfilled:

yes

Conclusions:

The 96 h-LC50 of BNMA in Pimephales promelas (Fathead minnow) is 4.67 mg/L (95% c.i. 4.25 - 5.3 mg/L). The 96 h-EC50 based in loss of equilibrium is 4.48 mg/L (95% c.i. 4.08 - 4.92 mg/L).

Executive summary:

In a 96-h acute toxicity study similar to OECD Guideline 203, Pimephales promelas (Fathead minnow) were exposed to BNMA at nominal (measured) concentrations of 0, 3.54 (3.02), 5.45 (4.54), 8.38 (7.03), 12.9 (11.2) and 19.9 (17.1) mg a.i./L under flow through conditions.  The 96-h LC50 was 4.67 mg a.i./L.  The EC50 value, based on sublethal effects, was 4.48 mg a.i./L.  Sublethal effects of loss of schooling behaviour, loss of equilibrium and hypoactivity were observed in the groups exposed to nominal 5.45 mg/L and higher of BNMA. 

This toxicity study is classified as acceptable and satisfies the guideline requirement for an acute toxicity study in fish.

 

Results Synopsis

 

Test organism size/age (length): 17.5 ± 2.038 mm, 29 days

Test Type: flow through

 

LC₅₀:  4.67 mg a.i./L (95% C.I. 4.25 - 5.13 mg a.i./L)                        

Endpoint(s) Effected: mortality

 

EC₅₀:  4.48 mg a.i./L (95% C.I. 4.08 - 4.92 mg a.i./L)                       

Endpoint(s) Effected: loss of schooling behaviour, loss of equilibrium, hypoactivity

Description of key information

The 96-h LC50 of BNMA in freshwater fish was 4.67 mg a.i./L. 

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

4.67 mg/L

Additional information

One acute freshwater study is available for BNMA. This study was found to be of good quality and assigned a Klimisch score of 2.

 

In a 96-h acute toxicity study similar to OECD Guideline 203, Pimephales promelas (Fathead minnow) were exposed to BNMA at nominal (measured) concentrations of 0, 3.54 (3.02), 5.45 (4.54), 8.38 (7.03), 12.9 (11.2) and 19.9 (17.1) mg a.i./L under flow through conditions.

The 96-h LC50 was 4.67 mg a.i./L.  The EC50 value, based on sublethal effects, was 4.48 mg a.i./L .  Sublethal effects of loss of schooling behaviour, loss of equilibrium and hypoactivity were observed in the groups exposed to nominal 5.45 mg/L and higher of BNMA.