Benzaldehyde

Long-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

fish, juvenile growth test

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: limited report, analytics poorly reported, non GLP

Qualifier:

no guideline followed

Principles of method if other than guideline:

The fathead minnow (Pimephales promelas) larval survival and growth test was used to evaluate the relative sensitivity of 1-, 4-, and 7-d-old larvae to the test substance.

GLP compliance:

not specified

Analytical monitoring:

yes

Details on sampling:

- Concentrations: For the test substance the first test nominal concentrations were 14.3, 7.2, 3.6, 1.8, and 0.9 mg/L, in the second set seven nomina concentrations were made, 7.2, 3.6, 1.8, 0.9, 0.45, 0.22, and 0.11 mg/L.
- Sampling: from stock solution on day 1 and 7 (stocks were renewed daily)
- Sampling method: not indicated
No additional data

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: 7 L of the high test concentrations were prepared daily in the dilution water and 7 L made by serial dilution (1:1) of the higher concentration. The high concentrations were prepared using 100 μL for the first test and 50 μL for the second.
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): water

No additional data

Test organisms (species):

Pimephales promelas

Details on test organisms:

TEST ORGANISM
- Common name: fathead minnow
- Strain: Pimephales promelas
- Source: the fathead minnow culture unit at the EPA Newtown Facility.
- Age at study initiation (mean and range, SD): 1-, 4-, and 7-d larvae
- Weight at study initiation (mean and range, SD): The mean dry weight of the 1-, 4- and 7-d larvae was 0.121, 0.173, 0.364 mg, respectively.
- Feeding during test: The 4- and 7-d larvae were not fed in the culture unit on the day the side-by-side test was started.

ACCLIMATION
- Type and amount of food: 1 g of trout chow starter food and 30 mL of a concentrated brine shrimp nauplii.
- Feeding frequency: The 1- and 7-d fish were fed 1 g of trout chow starter food two times a day and 30 mL of a concentrated brine shrimp nauplii once a day. The 4- and 7-d larvae were not fed in the culture unit on the day the side-by-side test was started.

No additional data

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

7 d

Post exposure observation period:

None stated

Hardness:

86 to 94 mg/L (as CaCO3)

Test temperature:

25±1℃

pH:

The initial measured pH had a mean value of 8.2 and ranged from 8.1 to 8.4. The mean of the final pH measurements was 7.5 (range 7.24–7.81).

Dissolved oxygen:

ca. 100% of saturation

Salinity:

None stated

Nominal and measured concentrations:

Nominal concentrations
First test: 14.3, 7.2, 3.6, 1.8, and 0.9 mg/L
Second test: 7.2, 3.6, 1.8, 0.9, 0.45, 0.22, and 0.11 mg/L

Measured concentrations
First test:
day 1 : 16.9, 8.5, 4.2, 2.1, 1.1 mg/L (118% of nominal)
day 7 : 0.20, 0.13, 0.02, ND, ND mg/L
mean (calculated by reviewer): 8.6, 4.3, 2.1, 1.1, 0.5 mg/L
Second test:
day 1 : 7.9, 4.0, 2.0, 1.0, 0.5, 0.24, 0.12 mg/L (110% of nominal)
day 7 : 0.07, 0.01, ND, ND, ND, ND, ND mg/L
mean (calculated by reviewer): 4.0, 2.0, 1.0, 0.5, 0.25, 0.12, 0.06 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 600 mL borosilicate glass beakers
- Material, size, headspace, fill volume: borosilicate glass, 600 mL, 350 mL, 250 mL
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- No. of vessels per vehicle control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Alkalinity: 56 to 64 mg/L

No additional data

Reference substance (positive control):

not specified

Duration:

7 d

Dose descriptor:

LOEC

Effect conc.:

0.9 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: For 1-d larvae

Duration:

7 d

Dose descriptor:

LOEC

Effect conc.:

0.5 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality

Remarks on result:

other: For 1-d larvae

Duration:

7 d

Dose descriptor:

NOEC

Effect conc.:

0.22 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: growth rate + survival

Remarks on result:

other: For 1-d larvae

Duration:

7 d

Dose descriptor:

NOEC

Effect conc.:

0.12 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

other: growth rate + mortality

Remarks on result:

other: For 1-d larvae

Duration:

7 d

Dose descriptor:

NOEC

Effect conc.:

1.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: For 7-d larvae

Duration:

7 d

Dose descriptor:

LOEC

Effect conc.:

3.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: For 7-d larvae

Details on results:

The 1-d larvae were more sensitive to this membrane irritant than the older larvae, and the 1-d larvae were more sensitive to the effect on survival while the older larvae were more sensitive to the effect on growth. In the first set the concentration of 0.90 mg/L was lethal to 87.5%, 12.5%, and 2.5% of the 1-, 4-, and 7-d larvae, respectively. The LOEC for the 1- and 4-d larvae was lower than the low test concentration of 0.90 mg/L. In the second setthe NOEC for 1 day larvae was established to be 0.22 mg/L (nominal)

Results with reference substance (positive control):

No information provided

Reported statistics and error estimates:

No information provided

Validity criteria fulfilled:

yes

Conclusions:

The subchronic toxicity of the test substance to the 7-d minnow larvae was 7 day NOEC = 1.8 mg/L (nominal).
The subchronic toxicity of the test substance to the 1-d minnow larvae was 7 day NOEC = 0.22 mg/L (nominal).

Executive summary:

The fathead minnow (Pimephales promelas) larval survival and growth test was used to evaluate the relative sensitivity of 1-, 4-, and 7-d-old larvae to the test substance.

The subchronic toxicity of the test substance to the 7-d minnow larvae was 7 day NOEC = 1.8 mg/L (nominal).

The subchronic toxicity of the test substance to the 1-d minnow larvae was 7 day NOEC = 0.22 mg/L (nominal).

Based on a calculation performed by the reviewer, the measured concentrations were 0.9 mg/L and 0.11 mg/L respectively.

Description of key information

In a larval survival and growth test with Pimephales promelas, 1-, 4-, and 7-d-old larvae were exposed to benzaldehyde for 7 days. A NOEC of 0.22 mg/L (nominal) (equivalent to 0.12 mg/L, as a measured geometric mean) was reported.

A supporting 14-day toxicity study in juvenile guppies reported an LD50 of 3.9 mg/L (measured).

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

0.12 mg/L

Additional information

Both studies show some defiencies. The study by Deneer was a semi-static study with renewal of the test substance on daily basis that included analytics of the test substance (only immediately after renewal). The study did not provide a value for a NOEC, but only an LC50 value (used to validate a QSAR).The analytics in the flow-through study by Pickering were poorly reported and no final conclusion on the measured concentrations was drawn by the authors. In a worst case approach the NOEC from this study based on measured values (calculation by reviewer) is used as starting point for the risk assessment.