3,4-dimethoxyphenethylamine

Bioaccumulation: aquatic / sediment

Description of key information

Significant accumulation in organisms of 3,4-Dimethoxyphenethylamine (CAS 120-20-7) is not to be expected.

Additional information

QSAR Disclaimer:

In Article 13 of Regulation (EC) No 1907/2006, it is laid down that information on intrinsic properties of substances may be generated by means other than tests, provided that the conditions set out in Annex XI (of the same Regulation) are met. Furthermore, according to Article 25 of the same Regulation testing on vertebrate animals shall be undertaken only as a last resort.

 

According to Annex XI of Regulation (EC) No 1907/2006 (Q)SAR results can be used if (1) the scientific validity of the (Q)SAR model has been established, (2) the substance falls within the applicability domain of the (Q)SAR model, (3) the results are adequate for the purpose of classification and labeling and/or risk assessment and (4) adequate and reliable documentation of the applied method is provided.

 

For the assessment of 3,4-Dimethoxyphenethylamine (CAS 120-20-7) (Q)SAR results were used for aquatic bioaccumulation. The criteria listed in Annex XI of Regulation (EC) No 1907/2006 are considered to be adequately fulfilled and therefore the endpoint(s) sufficiently covered and suitable for risk assessment.

 

Therefore, and for reasons of animal welfare, further experimental studies on aquatic bioaccumulation are not provided.

 

Assessment:

In accordance with column 2 of REACH Annex IX the study does not need to be conducted since the substance has a log Kow less or equal than 3. The substance (CAS 120-20-7) has a log Kow of -1.15 (measured at pH 7, 25 °C; BASF AG, 1991, report no. 91P04664).

No experimental data on the bioaccumulation potential of 3,4-Dimethoxyphenethylamine are available. In order to assess the bioaccumulation potential of the test substance, the BCF was calculated with several estimation models. The table below lists the applied (Q)SAR models, the estimated BCF values and basic information on the applicability domain (AD) for the compound. Detailed information on the model’s results and the AD are given in the endpoint study records of IUCLID Chapter 5.3.1. The selected models comply with the OECD principles for (Q)SAR models.

 

Summary of relevant information on aquatic bioaccumulation: Predicted BCF values for applied QSAR models sorted by BCF:

(AD = Applicability Domain)

Model	BCF [L/kg]	In AD	Restraints
BCFBAF v3.01 (EPI Suite v4.11):Arnot-GobasBCF, upper trophic, incl. biotransformation	0.89	No	The substance appreciably ionizes at physiologically relevant pH
BCFBAF v3.01 (EPI Suite v4.11):Arnot-GobasBCF, upper trophic, incl. biotransformation of zero	0.9	No	The substance appreciably ionizes at physiologically relevant pH
CAESAR v2.1.14 (VEGA v1.1.3)	2	No	The following relevant fragment have been found: NH2 group (PG 07). This group increases the hydrophilicity of a compound which is related to lower values of BCF. - only moderately similar compounds with known experimental value in the training set have been found - accuracy of prediction for similar molecules found in the training set is not adequate - the maximum error in prediction of similar molecules found in the training set has a high value, considering the experimental variability
Meylan v1.0.3 (VEGA v1.1.3)	3	No	- only moderately similar compounds with known experimental value in the training set have been found - the maximum error in prediction of similar molecules found in the training set has a moderate value, considering the experimental variability
BCFBAF v3.01 (EPI Suite v4.11):Meylanet al. (1997/1999)	3.2	Yes	-
BCF KNN/Read-Across v1.1.0 (VEGA v1.1.3)	3.6	No	- the maximum error in prediction of similar molecules found in the training set has a moderate value, considering the experimental variability
BCF baseline model v.02.09 (OASIS Catalogic v5.11.19): incl. mitigating factors	3.6	No	With regard to the parametric, structural and mechanistic domain, the test substance is not within the structural applicability domain of the model.
BCF baseline model v.02.09 (OASIS Catalogic v5.11.19): not considering mitigating factors	12.5	No	With regard to the parametric, structural and mechanistic domain, the test substance is not within the structural applicability domain of the model.
US EPA T.E.S.T. v4.2.1: Bioaccumulation: Consensus method	21.6	Yes	Based on the mean absolute errors of the models compared to the training set data, the confidence in the predicted results is high. For the comparison with the external test set no statement can be made, as no chemical exceeded a minimum similarity coefficient of 0.05.

 

Considering all models applied for 3,4-Dimethoxyphenethylamine (CAS 120-20-7), the estimated BCF values range from 0.89 to 21.6 L/kg. Based on the available information on the logKow (log Kow = -1.15; measured @ pH 7, 25°C; BASF AG, 1991 Rep. no.: 91P04664) can be concluded that accumulation of 3,4-Dimethoxyphenethylamine (120-20-7) in organisms is not to be expected.