Pent-1-ene

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

From 2017-07-13 to 2017-07-17

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

QSAR predictions

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

not applicable

Remarks:

(QSAR model)

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

not applicable

Remarks:

(QSAR model)

Principles of method if other than guideline:

The purpose of this QSAR model is to accurately predict the acute toxicity to fish as would be expected in a laboratory experiment following the OECD Guideline 203 (1) and EC method C.1 (2) for specific, named modes of action to provide a value that can effectively replace a 96-hour LC50 value from an experimental study. The regression based method used to achieve this has been fully validated following the OECD (2004) (3) recommendations (refer to the QMRF with JRC/KREATiS QMRF identifier: Q19-46-51-448 for further details).

GLP compliance:

no

Specific details on test material used for the study:

Not applicable

Analytical monitoring:

no

Remarks:

all tests used in the training set were based on measured data or on convincing evidence theat the test concentration was stable in the study; The results of the QSAR are therefore equivalent to measured concentrations

Details on sampling:

Not applicable

Vehicle:

no

Details on test solutions:

Not applicable

Test organisms (species):

other: Danio rerio, Oncorhynchus mykiss, Lepomis macrochirus, Pimephales promelas, Oryzias latipes, Leuciscus idus

Details on test organisms:

Results from the following species were used in the regression: Danio rerio, Oncorhynchus mykiss, Lepomis macrochirus, Pimephales promelas, Oryzias latipes, Leuciscus idus.
Following the principles of Phase Equilibrium Thermodynamics, for narcotic substances, no difference in relationship between solubility and ecotoxicity between fish freshwater species is expected. Any observed differences may be attributed to lifestyle related parameters (e.g. relative differences in storage lipid content between species) and relative duration of study versus bodysize rather than to a specific toxic mechanism causing species differences. In this case, for non-polar narcotic compounds, no differences were observed in activity based toxicity for the species used.

Test type:

other: QSAR

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Remarks on exposure duration:

none

Post exposure observation period:

None

Hardness:

The QSAR is based on data from studies performed at acceptable hardness to ensure control survival.

Test temperature:

The temperatures varied from approximately 14 to 25 °C depending on the fish species used to construct the algorithm. While it is recognized that this may contribute to some extent to the variability of the LC50 values found in experimental data, KREATiS has not observed a clear trend suggesting that normalization to temperature would necessarily improve the algorithm (say for trout as opposed to warm water species) for mono-constituents. Nevertheless, this is a recognized area for further research by KREATiS.

pH:

The QSAR is based on data from studies performed with measured pHs between 6.0 - 8.5.

Dissolved oxygen:

The QSAR is based on data from studies performed at acceptable oxygen concentrations (generally >60%).

Salinity:

Not applicable

Nominal and measured concentrations:

The QSAR is based on data from studies performed using measured concentrations or with acceptable stability.

Details on test conditions:

A variety of test designs were accepted: Preferentially results from a semi-static with daily renewal of test solutions and the control or from a flow-through test were used. However, for stable, low volatility substances a static design was accepted (preferably accompanied by analytical measurements over the study period). For suspected volatile substances only tests performed in closed vessels were accepted unless accompanying analytical monitoring proved such a design was not necessary.

Reference substance (positive control):

no

Remarks:

(QSAR model)

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

5.9 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CL: 5.4-6.5 mg/L

Details on results:

The predicated value is reliable since the test substance falls within the applicability domain of the model. The water solubility value of the test substance is within descriptor domain of the model between log water solubility (in log (mol/L)) of -4.63 to 0.87. Moreover the test substance is attributed to the class of non-polar narcotic compounds.

Results with reference substance (positive control):

Not applicable

Reported statistics and error estimates:

95% CL: 5.4-6.5 mg/L
QSAR statistical parameters are given in the QMRF and the QPRF

Sublethal observations / clinical signs:

No additional information

Validity criteria fulfilled:

yes

Remarks:

The substance falls into the applicability domains of the QSAR model.

Conclusions:

The 96-h LC50 based on mortality and measured concentrations was determined to be 5.9 mg/L with 95%-Confidence Limit between 5.4 and 6.5 mg/L.

Executive summary:

A High Accuracy Quantitative Structure Activity Relationship (HA-QSAR) model was used to calculate the acute toxicity to fish exposed to the test item pent-1-ene. This QSAR model has been validated to be compliant with the OECD recommendations for QSAR modeling (OECD, 2004) and predicts the endpoint value which would be expected when testing the substance under experimental conditions in a laboratory following the Guideline for Testing of Chemicals No. 203, "Fish Acute Toxicity Test" (1), referenced as Method C.1 of Commission Regulation No. 440/2008 (2). The criterion predicted was the LC50 (Median Lethal Concentration), a statistically derived concentration which is expected to cause mortality in 50% of test animals within a period of 96 hours.

The acute toxicity to fish was determined using a validated QSAR for the Mode of Action (MOA) in question, i.e. non-polar narcosis (MOA1). The QSAR is based on validated data for a training set of 67 chemicals derived from 96-hour test on fish, for which the concentrations of the test item had been determined by chemical analyses over the test period.

The 96-h LC50 based on mortality and measured concentrations was determined to be 5.9 mg/L with 95%-Confidence Limit between 5.4 and 6.5 mg/L.

Description of key information

QSAR model, iSafeRat holistic approach v1.7, key study, validity 1:

96h-LC50 = 5.9 mg/L (95% CL: 5.4 - 6.5 mg/L).

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

5.9 mg/L

Additional information

To assess the toxicity of the registerd substance to fish, one data point is available.

A High Accuracy Quantitative Structure Activity Relationship (HA-QSAR) model was used to calculate the acute toxicity to fish exposed to the test item pent-1-ene. This QSAR model has been validated to be compliant with the OECD recommendations for QSAR modeling (OECD, 2004) and predicts the endpoint value which would be expected when testing the substance under experimental conditions in a laboratory following the Guideline for Testing of Chemicals No. 203, "Fish Acute Toxicity Test" (1), referenced as Method C.1 of Commission Regulation No. 440/2008 (2). The criterion predicted was the LC50 (Median Lethal Concentration), a statistically derived concentration which is expected to cause mortality in 50% of test animals within a period of 96 hours.

The acute toxicity to fish was determined using a validated QSAR for the Mode of Action (MOA) in question, i.e. non-polar narcosis (MOA1). The QSAR is based on validated data for a training set of 67 chemicals derived from 96-hour test on fish, for which the concentrations of the test item had been determined by chemical analyses over the test period.

The 96-h LC50 based on mortality and measured concentrations was determined to be 5.9 mg/L with 95%-Confidence Limit between 5.4 and 6.5 mg/L.