Benzene, 1,1'-oxybis-, tetrapropylene derivs., sulfonated, sodium salts

Bioaccumulation: aquatic / sediment

Description of key information

Waived:  log Pow = -2.68

Additional information

In accordance with Column 2 of REACh Annex IX, the study need not be conducted if the substance has a low potential for bioaccumulation (log Pow < 3) and/or low potential to cross biological membranes. The estimated log Pow of the substance is -2.68, based on ratio of solubilities in 1 -octanol and water.

Measured bioconcentration of the structurally-analogous C12 -C14 linear alkylbenzene sulfonate (LAS) surfactants in fathead minnow and Daphnia magna ranged from 269 - 1,223 and 500 - 4,000 L/Kg (dry wt.), respectively. The bioconcentration factors reported here can be regarded as highly conservative, as they are based on measurements of total radioactivity in fish tissues and in water, and do not account for potential/expected metabolism and expression of radioactivity as metabolites in tissues. Furthermore, the BCF values are based on dry wt. of tissue, whereas BCF is typically expressed on a wet wt., whole-tissue basis. The fish BCF values are therefore aprroximately 4-fold higher than as would be if reported on wet wt. (whole tissue) basis. Therefore, DOWFAX 2A1 does not likely exceed the criteria for high or very high bioaccumulation in aquatic organisms (i.e., BCF > 2,000 and 5,000; respectively). Both LAS and DOWFAX 2A1 posses the common structural features of sulfonated aromatic ring and C12 alkyl substituents; therefore, their modes and potential for metabolism in fish should be equivalent. Both substanes are reported to be miscible in water. The DOWFAX 2A1 components have slightly higher lipophilicity, with calculated log Pow (US EPA KOWWIN v.167) ranging from 4.98 to 11.8; while that for components of LAS range from 4.71 to 5.69.