α-methyl-1,3-benzodioxole-5-propionaldehyde

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

long-term toxicity to aquatic invertebrates

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Reference 2

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Study period:

2022

Reliability:

2 (reliable with restrictions)

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:

For detailed description of the model and its applicability domain, see attached QMRF and QPRF document.

Qualifier:

according to guideline

Guideline:

other: REACH guidance on QSAR R.6

Principles of method if other than guideline:

Calculation of Long-Term toxicity in daphnids. Software used: ECOSAR 2.0 for chemical class "Aldehydes (Mono)"

GLP compliance:

no

Specific details on test material used for the study:

SMILES: CC(Cc1ccc2OCOc2c1)C=O

Analytical monitoring:

not required

Test organisms (species):

other: daphnia

Water media type:

freshwater

Total exposure duration:

21 d

Remarks on exposure duration:

chronic exposure

Key result

Duration:

21 d

Effect conc.:

0.08 mg/L

Remarks on result:

other: ChV (chronic value, QSAR); The substance is within the applicability domain of the model.

Organism	Duration	Endpoint	Concentration (mg/L)	Max Log Kow	Flags
Fish	96h	LC50	7.54	5
Daphnid	48h	LC50	6.61	5
Green Algae	96h	EC50	4.07	6.4
Fish		ChV	0.87	8
Daphnid		ChV	0.08	8
Green Algae		ChV	1.71	8

Validity criteria fulfilled:

yes

Conclusions:

Using ECOSAR v2.0 the long-term toxicity ChV value for daphnids was calculated to be 0.08 mg/L. The substance is within the applicability domain of the model.

Executive summary:

The long-term toxicity in fish was calculated using ECOSAR v2.0 from US Environmental Protection Agency.

 

The adequacy of a prediction depends on the following conditions:

a) the (Q)SAR model is scientifically valid: the scientific validity is established according to the OECD principles for (Q)SAR validation;

b) the (Q)SAR model is applicable to the query chemical: a (Q)SAR is applicable if the query chemical falls within the defined applicability domain of the model;

c) the (Q)SAR result is reliable: a valid (Q)SAR that is applied to a chemical falling within its applicability domain provides a reliable result;

d) the (Q)SAR model is relevant for the regulatory purpose.

 

For assessment and justification of these 4 requirements the QMRF and QPRF files were developed and attached to this study record.

 

Description of the prediction Model

The prediction model was descriped using the harmonised template for summarising and reporting key information on (Q)SAR models. For more details please refer to the attached QSAR Model Reporting Format (QMRF) file. 

 

Assessment of estimation domain

The assessment of the estimation domain was documented in the QSAR Prediction Reporting Format file (QPRF). Please refer to the attached document for the details of the prediction and the assessment of the estimation domain.

Description of key information

According to Annex XI, paragraph 1.3 results obtained from valid QSAR models may be used instead of testing. A QSAR calculation is available for this endpoint showing that the substance is not chronic toxic to daphnids.

Based on the results of the QSAR calculation for the long-term toxicity to daphnids, the information from the short-term aquatic toxicity tests with fish, daphnia and algae and the information from the chronic algae and daphnia tests - it can be shown that the substance is not aquatic toxic. Thus, to avoid unnecessary testing on vertebrate animals no additional test on long-term toxicity to daphnids is needed to be able to conclude on the non-toxicity of the substance for aquatic organisms.

Furthermore, this is supported by the good solubility in water (934000 mg/L) and the low bioaccumulation potential (log Kow = 2.4).

For further justification, please refer to 'Additional information'.

Additional information

Long-term toxicity testing on aquatic invertebrates (Annex IX, Section 9.1.5.; test method: EU C.20./OECD TG 211)

The Registrant adapts the information requirements under Annex IX of REACH with regard to long-term toxicity testing on aquatic invertebrates in accordance with Annex XI, Section 1.3 by providing the requested information using an appropriate QSAR method. Additionally, an Expert Judgement was performed in order to support the evidence that the substance is not expected to be chronically harmful to aquatic invertebrates. A robust study summary of the QSAR estimation and the Expert Judgement is provided below.

 

QSAR data on long-term toxicity to aquatic invertebrates

The long-term toxicity on aquatic invertebrates has been assessed using ECOSAR v2.0 (US Environmental Protection Agency). The long-term toxicity (21 d) value for daphnids was calculated to be 0.08 mg/L, showing that the substance is not chronic toxic to daphnia. The substance is within the applicability domain of the model.

 

Expert Judgement

The structure as well as the physico-chemical properties of the Substance are clearly identified. The substance was shown to be not rapidly, but inherently biodegradable (Rudio, 1998; Desmares-Koopmans, 2002). However, it is regarded as being potentially persistent (P) or very persistent (vP) according to the ECHA Guidance on PBT/vPvB assessment (2017). Based on the log Know value of 2.4 the substance has no potential for bioaccumulation. Even though none of the endpoints for aquatic ecotoxicity (NOEC, EC50, LC50 and EC10) are < 0.1 mg/L (the trigger value for toxicity (T)), α-methyl-1,3-benzodioxole-5-propionaldehyde (HLF) does fulfil the toxicity (T) criteria as it is classified as toxic for reproduction (category 2, H361). It is classified for chronic aquatic toxicity into Category 2 (H411) according to  Regulation (EC) No 1272/2008. This classification is triggered by the absence of chronic toxicity data in combination with the substance being not readily biodegradable.

Reliable QSAR predictions for long-term toxicity to aquatic invertebrates and fish are available for the substance. The long-term toxicity in fish was calculated using ECOSAR v2.0 from US Environmental Protection Agency. The long-term toxicity value for fish was calculated to be 0.87 mg/L.

The long-term NOEC of 0.08 mg/L for aquatic invertebrates and the long-term NOEC of 0.87 mg/L for fish indicate that long-term effects on aquatic invertebrates and fish are not to be expected. Moreover, the Substance was studied in short-term aquatic tests (algae, daphnia and fish). In the acute toxicity study with fish (Oncorhynchus mykiss, Parr, 2015), a 96 h LC50 value of 5.3 mg/L was observed. The Lowest Observed Effect Concentration and No Observed Effect Concentration based on mean-measured test concentrations were considered to be 4.5 and 2.4 mg/L, respectively. The short-term toxicity test to aquatic invertebrates (Daphnia magna, Lenertz, 2001) revealed an 48 h EC50 of 8.3 mg/L. The 72 h ErC50 for algae (Pseudokirchneriella subcapitata, Vryenhoef, 2013) was determined to be 28 mg/L, the NOEC and LOEC values based on the growth rate were determined to be 6.25 and 12.5 mg/L, respectively. The 72 h EyC50 was determined to be 14 mg/L (95 % CL 13 to 16 mg/L); the NOEC and LOEC values based on the yield were determined to be 6.25 and 12.5 mg/L, respectively.

The available short-term toxicity data for the three trophic levels (fish, aquatic invertebrates and algae, please see table below) do not indicate a concern for a high sensitivity of aquatic invertebrates.

_{Table 1. Key results from short-term toxicity aquatic tests}

Test organism	Key result [mg/L]	Test Guidance	Reference
Fish (Oncorhynchus mykiss)	96 h LC50 = 5.3	OECD 203	Parr, 2015
Aquatic invertebrates (Daphnia magna)	EC50 = 8.3	OECD 202	Lenertz, 2001
Algae (Pseudokirchneriella subcapitata)	EC50 = 28 NOEC = 6.25	OECD 201	Vryenhoef, 2013

Taken together, the intrinsic properties of the Substance indicate that significant and relevant long-term effects on aquatic invertebrates are not expected to occur. The substance has no specific mode of action and does not produce structural alerts for relevant effects.

The Substance has no specific mode of action and does not produce structural alerts for relevant effect. Overall, it can be concluded, that the available data on the Substance’s toxicity and properties lead to the conclusion that the substance has not a particular dangerous or harmful property in terms of the long-term toxicity to daphnia. Therefore, further testing does not seem justified and long-term toxicity testing on aquatic invertebrates will not be performed.

 

References:

ECHA (2017). Guidance on Information Requirements and Chemical Safety Assessment Chapter R.11: PBT/vPvB assessment. Version 3.0, June 2017. ECHA-17-G-12-EN.