reaction mass of N1,N3-bis(3-aminopropyl)-2-methyl-cyclohexane-1,3-diamine and N1,N3-bis(3-aminopropyl)-4-methyl-cyclohexane-1,3-diamine

Bioaccumulation: aquatic / sediment

Description of key information

Significant accumulation of DAP-MCDA in organisms 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 reaction mass of N1,N3-bis(3aminopropyl)-2-methyl-cyclohexane-1,3-diamine and N1,N3-bis(3aminopropyl)-4-methyl-cyclohexane-1,3-diamine (DAP-MCDA) (Q)SAR results were used for the estimation of the bioaccumulation factor. 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

No studies are available for the bioaccumulation assessment of the substance. According to Regulation (EC) 1907 (2006) Annex IX, Section 9.3.2, Column 2, a study on bioaccumulation does not need to be conducted as the substance has a low potential for bioaccumulation. The substance has an estimated log Kow of 0.46 (calculated for the representative constituents N1,N3-bis(3-aminopropyl)-4-methyl-cyclohexane-1,3-diamine (BI 858010) and N1,N3-bis(3-aminopropyl)-2-methyl-cyclohexane-1,3-diamine (BI 858015), see IUCLID chapter 4.7). Regarding these values, accumulation of the test substance in organisms is not to be expected. Therefore, and for reasons of animal welfare, a study on bioaccumulation is not provided. In addition, this is not an informatin requirement for the tonnage band of the substance to be registered in: 1 -10 t per year non-intermediate.

In order to assess the bioaccumulation potential of the substance, the BCF was additionally calculated with several estimation models for the two representative constituents (Table 1).

 Table 1. Estimated BCF values for the two representative constituents of DAP-MCDA

Model	BCF [L/kg]	In AD	Restraints
BI 858010
BCFBAF v3.01 (EPI Suite v4.11): Arnot-Gobas BCF, upper trophic, incl. biotransformation	1.2	no	The calculation methods may be less accurate, due to the substance's property to appreciably ionize at physiological pH.
BCFBAF v3.01 (EPI Suite v4.11): Arnot-Gobas BCF, upper trophic, excl. biotransformation	1.2	no	The calculation methods may be less accurate, due to the substance's property to appreciably ionize at physiological pH.
BCF base-line model v3.10 (OASIS Catalogic v5.13.1): Considering all mitigating factors	2.0	no	With regard to the structural domain, the substance is not within the applicability domain of the model. Therefore, the estimation is not reliable.
BCFBAF v3.01 (EPI Suite v4.11): Meylan et al. (1997/1999)	3.2	yes	-
US EPA T.E.S.T. v4.2.1: Consensus method	5.1	yes	-
BCF base-line model v3.10 (OASIS Catalogic v5.13.1): Without considering any mitigating factors	11.4	no	With regard to the structural domain, the substance is not within the applicability domain of the model. Therefore, the estimation is not reliable.
BI 858015
BCFBAF v3.01 (EPI Suite v4.11): Arnot-Gobas BCF, upper trophic, incl. biotransformation	1.2	no	The calculation methods may be less accurate, due to the substance's property to appreciably ionize at physiological pH.
BCFBAF v3.01 (EPI Suite v4.11): Arnot-Gobas BCF, upper trophic, excl. biotransformation	1.2	no	The calculation methods may be less accurate, due to the substance's property to appreciably ionize at physiological pH.
BCF base-line model v3.10 (OASIS Catalogic v5.13.1): Considering all mitigating factors	2.0	no	With regard to the structural domain, the substance is not within the applicability domain of the model. Therefore, the estimation is not reliable.
BCFBAF v3.01 (EPI Suite v4.11): Meylan et al. (1997/1999)	3.2	yes	-
US EPA T.E.S.T. v4.2.1: Consensus method	3.3	yes	-
BCF base-line model v3.10 (OASIS Catalogic v5.13.1): Without considering any mitigating factors	11.4	no	With regard to the structural domain, the substance is not within the applicability domain of the model. Therefore, the estimation is not reliable.

 

The two constituents were within the applicabilit domain (AD) of the Meylan et al. submodel (BCFBAF v3.01, EPI Suite v4.11) and the consensus method (US EPA T.E.S.T. v4.2.1), but not in the AD of the other models. The results using Arnot &Gobas (2003) method may be less accurate due to the substances ability to appreciably ionize at physiological pH.

Since there are no experimental data on the bioaccumulation of DAP-MCDA, the data from its representative constituents were used to estimate the bioaccumulation potential of the substance. The estimated BCF values ranged from 1.2 to 11.4 L/kg (Table 1). Therefore, based on a weight-of-evidence approach, significant accumulation in organisms is not to be expected.