3-(p-cumenyl)-2-methylpropionaldehyde

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:

2017-07-09 to 2017-08-18

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Name (as stated in the report): Silvial
Batch No.: SC00017272
Expiration date: 2017-10-13
Chemical Name: 2-METHYL-3-(4-(2-METHYLPROPYL)PHENYL)PROPANAL
Purity: 99.0%

Analytical monitoring:

yes

Details on sampling:

Each test concentration and the control were analytically verified via HPLC-DAD from freshly prepared media after 0 and 72 hours and from corresponding aged test media after 24 and 96 hours.
The samples were stabilized with acetonitrile containing 0.2% H3PO4 with a dilution factor of 2 directly after sampling. Excluding the highest test concentration which was diluted with acetonitrile : HPLC water (50 : 50) containing 0.1% H3P04, the samples were analyzed without further dilution. All samples were stored at 6 ± 2 °C until the start of the analysis,if necessary. Prepared samples were stored in the autosampler at room temperature until analysis.

Vehicle:

no

Details on test solutions:

Media preparation trials performed as part of an algal inhibition test (KLIX, 2017a) indicated that the saturated solution method was the most suitable method of preparation for the test item.
A saturated solution with a nominal loading of 100 mg/L test item was prepared with dilution water 24 ± 1 hour prior to the start of the exposure. The test item was placed onto the surface of the dilution water with a pipette. A slow stirring procedure was applied. Gentle stirring (to avoid formation of an emulsion) was carried out with a magnetic stirrer at room temperature for 24 ± 1 hour. After a separation phase of at least 1 hour at room temperature the saturated solution was taken from the homogeneous phase in the middle of the flask and diluted to 3.13 - 6.25 - 12.5 - 25 - 50 % with dilution water. The prepared dilution levels were used for testing. The saturated solution was checked after stirring via laser beam (Tyndall effect) for undissolved test item (formation of an emulsion) at the start of the first exposure interval. No Tyndall effect was observed. The test media was clearly dissolved throughout exposure. The test vessels were covered with a floating lid. This procedure was repeated for every water renewal.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

All fish used in the test was gained at Noack Laboratorien GmbH from a single brood stock (supplier: Umweltbundesamt, Schichauweg 58, D-12307 Berlin)
Holding was performed at the test facility at 23 ± 2 °C and diffuse light (7 - 750 Lux, natural photoperiod). The water was changed at least once per week. The dissolved oxygen concentration was more than 80 % of the air saturation value. Zebrafish with at least 12 days of acclimatisation and mortality < 5 % within these days prior to the start of the exposure were used in the test. No mortality was observed during this time. No disease treatments were administered throughout holding and testing.
Food was provided 3 times per week. The amount of food was 4 % of the fish body weight per feeding day. The test fish were not be fed 24 h before test start.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

87 mg/L as CaC03

Test temperature:

23 + 2 °C, controlled at ± 1 °C

pH:

6.86 - 7.52

Dissolved oxygen:

Not less than 60 % of air saturation value.

Nominal and measured concentrations:

The saturated solution was diluted to 3.13 - 6.25 - 12.5 - 25 - 50 % (factor 2) of the saturated solution, corresponding to geometric mean measured concentrations of 1.83 - 3.71 - 7.92 - 16.2 - 39.7 mg/L (Sum of the Analytes : Parent and Metabolite)

Details on test conditions:

A semi-static test with daily renewal of the test media was performed. With regard to the properties of the test item, the test aquaria were covered with a floating lid (i.e. with aluminium foil) to reduce the loss of the test item via the surface.
Seven zebrafish were used for each test concentration and the control. Fish density in the test vessels was 0.17 g fish per litre test solution. Average body length at the test start: 2.63 cm Average body weight at the test start: 0.19 g. Fish were introduced randomly to individual replicate and not fed during the test.
No aeration was provided.
Water quality parameters (temperature, pH-value and oxygen-saturation) measured at 0, 24, 48, 72 and 96 hours were determined to be within the acceptable limits.

Reference substance (positive control):

no

Remarks:

No reference item is recommended for this test according to the guidelines.

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

11.3 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Validity criteria fulfilled:

yes

Remarks:

All validity criteria of the test guideline were met.

Conclusions:

In this study Silvial was found to cause lethal effects to zebrafish after 96 hours at a geometric mean measured test item concentration of 16.2 mg/L and higher. The LC50 after 96 hours was 11.3 mg test item/L. The LC0 and LC100 after 96 hours was 7.92 and 16.2 mg test item/L (geometric mean measured test item concentration).

Executive summary:

The acute toxicity of the test item Silvial (batch no. SC00017272) to fish (zebrafish) was determined according to the principles of the OECD-Guideline for Testing of Chemicals No. 203 (1992) and EU Council Regulation (EC) No. 440/2008/ Method C.1 (2008) from 2017-07-09 to 2017-08-18 with a definitive exposure phase from 2017-08-14 to 2017-08-18 at the test facility.

An acute toxicity test under semi-static conditions with daily renewal of the test media was conducted. A saturated solution of nominal 100 mg/L was prepared. This method of preparation for the test item was considered to be the most appropriate following media preparation trials performed as part of an algal inhibition study (KLIX, 2017a). The saturated solution was diluted to 3.13 - 6.25 - 12.5 - 25 - 50 % (factor 2) of the saturated solution, corresponding to geometric mean measured concentrations of 1.83 - 3.71 - 7.92 - 16.2 - 39.7 mg/L. Duration of the test was 96 hours. Seven test organisms were exposed to each test concentration and the control. Water quality parameters (temperature, pH-value and oxygen-saturation) measured at 0, 24, 48, 72 and 96 hours were determined to be within the acceptable limits.

Based on information provided by the sponsor, the test item was known to be rapidly degraded, even during preparation of the saturated solution. One metabolite is formed, which has been confirmed to be 3-(4-isobutylphenyl)-2-methylpropanoic acid.

The concentrations of the test item (parent and metabolite) were analytically verified via HPLC- DAD from freshly prepared media after 0 and 72 h and from corresponding 24 h aged test media after 24 and 96 h. The measured concentrations of the test item and metabolite at the start of all exposure intervals after 0 and 72 hours were between 68 and 100% of the expected values based on the analysis of the highest concentrated sample. At the end of all exposure intervals after 24 and 96 hours the measured concentrations of the test item incl. metabolite were between 83 to 103% of the initial measured concentrations.

Since the biological effects observed are produced by the mixture of parent substance and metabolite, it is considered justifiable to base all effect values on the geometric mean measured test item concentrations of Silvial (parent substance and the calculated concentration of parent based on the measured concentration of the metabolite), which were calculated to be: 1.83 - 3.71 - 7.92 - 16.2 - 39.7 mg/L.

In this study Silvial was found to cause lethal effects to zebrafish after 96 hours at a geometric mean measured test item concentration of 16.2 mg/L and higher. The LC50 after 96 hours was 11.3 mg test item/L. The LC0 and LC100 after 96 hours was 7.92 and 16.2 mg test item/L (geometric mean measured test item concentration).

Description of key information

The acute toxicity of the test item Silvial (batch no. SC00017272) to fish (zebrafish) was determined according to the principles of the OECD-Guideline for Testing of Chemicals No. 203 (1992) and EU Council Regulation (EC) No. 440/2008/ Method C.1 (2008) from 2017-07-09 to 2017-08-18 with a definitive exposure phase from 2017-08-14 to 2017-08-18 at the test facility.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

11.3 mg/L

Additional information

The study was conducted under semi-static conditions with daily renewal of the test media. A saturated solution of nominal 100 mg/L was prepared. This method of preparation for the test item was considered to be the most appropriate following media preparation trials performed as part of an algal inhibition study (KLIX, 2017). The saturated solution was diluted to 3.13 - 6.25 - 12.5 - 25 - 50 % (factor 2) of the saturated solution, corresponding to geometric mean measured concentrations of 1.83 - 3.71 - 7.92 - 16.2 - 39.7 mg/L. Duration of the test was 96 hours. Seven test organisms were exposed to each test concentration and the control. Water quality parameters (temperature, pH-value and oxygen-saturation) measured at 0, 24, 48, 72 and 96 hours were determined to be within the acceptable limits.

The test item was known to be rapidly degraded, even during preparation of the saturated solution. One metabolite is formed, which has been confirmed to be 3-(4-isobutylphenyl)-2-methylpropanoic acid. The concentrations of the test item (parent and metabolite) were analytically verified via HPLC- DAD from freshly prepared media after 0 and 72 h and from corresponding 24 h aged test media after 24 and 96 h. The measured concentrations of the test item and metabolite at the start of all exposure intervals after 0 and 72 hours were between 68 and 100% of the expected values based on the analysis of the highest concentrated sample. At the end of all exposure intervals after 24 and 96 hours the measured concentrations of the test item incl. metabolite were between 83 to 103% of the initial measured concentrations.

Since the biological effects observed are produced by the mixture of parent substance and metabolite, it is considered justifiable to base all effect values on the geometric mean measured test item concentrations of Silvial (parent substance and the calculated concentration of parent based on the measured concentration of the metabolite), which were calculated to be: 1.83 - 3.71 - 7.92 - 16.2 - 39.7 mg/L.

In this study Silvial was found to cause lethal effects to zebrafish after 96 hours at a geometric mean measured test item concentration of 16.2 mg/L and higher. The LC50 after 96 hours was 11.3 mg test item/L. The LC0 and LC100 after 96 hours was 7.92 and 16.2 mg test item/L (geometric mean measured test item concentration).