Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Stability

The stability of the substance was determined according to the OECD guideline 111 and the EU method, C. 7 (Currenta, 2009). Based on kinetic parameters, the following dissipation half-lives for a temperature of 25 °C were extrapolated based on the Arrhenius equation:

pH 4 (25 °C): > 1 year

pH 7 (25 °C): 573 days

pH 9 (25 °C): 15 days.

The calculated half-life of the substance in air due to indirect photo degradation is 0.4 days, considering an OH-concentration of 500,000 radicals/cm³ as a 24-h average (Currenta, 2010). As representative 2-[2-(2-hydroxyethoxy)ethoxy]ethyl 2-hydroxyethyl phthalate was used for calculation of the photo transformation in air, as the substance is a UVCB-substance.

Biodegradation

A test on ready biodegradability showed that 50 % of the substance is degraded within 28 days. These results show that the substance is not readily biodegradable, but additionally provided evidence from an inherent test show that the substance can be degraded in sewage treatment plants. The substance is not readily biodegradable, but inherent biodegradable (Bayer AG, 1994; Currenta, 2009).

Bioaccumulation

From the octanol-water partition coefficient a bioconcentration factor of 2.9 is calculated with the BCFBAF-Program using 2-[2-(2-hydroxyethoxy)ethoxy]ethyl 2-hydroxyethyl phthalate as the representative of this UVCB-substance. Taking the measured logKow of 1.6 into account a BCF of 2.9 is estimated by the program. This value is supported by the logKow, indicating that the substance has no potential for bioaccumulation.

Adsorption / desorption

The measured Koc-value of the substance is 100 at pH 6.3 estimated by OECD Guideline 121 (Estimation of the Adsorption Coefficient (Koc) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC) (Currenta, 2009).This indicates only a low potential for adsorption.

Henry's Law constant

The Henry's Law Constant of 0.00054 Pa m³/mol at 25 °C of the substance is directly calculated as a ratio of the vapour pressure to the water solubility (Currenta, 2010). According to the classification scheme of Thomas (1990), the substance is low volatile from surface waters. As the substance is a UVCB-substance, 2-[2-(2-hydroxyethoxy)ethoxy]ethyl 2-hydroxyethyl phthalate was used as the representative of this UVCB-substance for calculation.