4-(1-methyl-1-phenylethyl)-N-[4-(1-methyl-1-phenylethyl)phenyl]aniline

Bioaccumulation: aquatic / sediment

Description of key information

Discussions on bioaccumulation potential

Key value for chemical safety assessment

BCF (aquatic species):

1 245 L/kg ww

Additional information

The substance has been demonstrated to have a very high partition coefficient value which demonstrates that the potential for this substance to accumulate biologically is limited, given that it is a high value of log P = 7.90 ± 1.22 (25°C, pH = 6.9). The high log Pow is considered to be more a consequence of poor water solubility issues than a lipophilic tendency and is considered to be not indicative of the tendency to bioaccumulate in lipid tissues of aquatic organisms. This is based on literature data which demonstrates a tendency for the Bioconcentration Factor (BCF) to decrease as Log Pow increases above 6. At a high value of 7.9, the substance is proposed not to bioaccumulate.  This is further confirmed via the use of the following QSAR tools:

 

·       CAESAR BCF Read-Across (version 1.0.0)

·       US EPA On-Line EPI Suite™v3.01 model BCFBAF

 

Which indicates that the substance is unlikely to bioaccumulate, with calculated values as follows:

 

	BCF value (L/kg wet-wt)	Log BCF value
BCF Read-Across (version 1.0.0)	888	2.95
US EPA On-Line EPI Suite™v3-01 model BCFBAF	1245	3.095

 

This QSAR prediction is supported by a radiolabelled toxicokinetic study on the substance. Within this study,¹⁴C radiolabelled test material was not extensively distributed into tissues of rats after an oral dose. The substance did not demonstrate high absorption from the gastrointestinal tract. And after 72h, the concentrations in the majority of tissues had decreased significantly. The above factors indicate that bioaccumulation within body tissues is unlikely.