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Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Stability

In general according to column 2 of REACH Annex VIII, a study for hydrolysis does not need to be conducted as bis(2-ethylhexyl) hydrogen phosphate is readily biodegradable.

Nevertheless in a read across approach with dibutyl hydrogen phosphate (CAS No. 107-66-4), the behaviour of bis(2-ethylhexyl) hydrogen phosphate against hydrolysis is assessed (OECD Guideline 111). Dibutyl hydrogen phosphate is shown to be stable at pH 4, 7 and 9 at 50°C. Therefore it can be assumed that also bis(2-ethylhexyl) hydrogen phosphate is stable against hydrolysis.

Biodegradation

With 75 % degradation within 28 days in a ready biodegradation study bis(2-ethylhexyl) hydrogen phosphate is considered as readily biodegradable. Therefore, bis(2-ethylhexyl) hydrogen phosphate will not persist in any environmental compartment. The OECD Guideline 301F was applied.

Biodegradation (water/sediment, soil)

Bis(2-ethylhexyl) hydrogen phosphate is considered as readily biodegradable. Therefore, performance of a study in water/sediment and soil does not appear scientifically necessary.

Bioaccumulation

According to OECD Guideline 305C with Cyprinus carpio as test organism BCF values lay in the range of 1.1 - 6.0. Determinations were conducted at concentrations of 0.1 and 1 mg/L. The received BCF values indicate that bis(2-ethylhexyl) hydrogen phosphate is not bioaccumulative.

Adsorption / desorption

Following the OECD Guideline 121 (HPLC method) a logKoc value of 2.4 was received. This value indicates that bis(2-ethylhexyl) hydrogen phosphate has a low sorption potential to soil and sediment.

Henry's Law Constant

The QSAR determination of the Henry's Law Constant for bis(2-ethylhexyl) hydrogen phosphate using the Estimation Program Interface (EPI) Suite v4.11 revealed a value of 0.00417 Pa*m³/mol at 25°C. This value indicates that bis(2-ethylhexyl) hydrogen phosphate is essentially non-volatile from water, and a long-range transport via the atmosphere is not expected.