Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Stability

Based on the structure of the test substance it can be concluded that it is generally resistant to hydrolysis because it does not contain any labile functional groups. This conclusion based on the structure is supported by a hydrolysis study (CIBA-GEIGY, 1985). Based on the results of the study it can be concluded, that the test item has a half-life time longer than one year at 25°C at pH 4.0 , 7.0 and 9.0.

Biodegradation

In the key study (Ciba-Geigy, 1985), the ready biodegradability of the test item was assessed over a 28 day period by the modified Sturm test (OECD 301B). The nominal test concentrations were 10 and 20 mg a.s./L. The test material attained up to 42 and 46 % biodegradation after 28 days. These results indicate that the test item cannot be classified readily biodegradable under conditions of the test, but it is moderately/partly biodegradable.

The Chemical Oxygen Demand of the test item was determined to be 1.86 g COD/g.

Bioaccumulation

Due to the results of a weight of evidence including a logPow below 3 and four different QSAR calculations, it can be concluded that the test substance does not significantly accumulate in organism

Transport and distribution

The pKa for the test substance was calculated to be 3.79 using SPARC (v4.6). This value indicates that the test substance will exist primarily as an anion in the environment (pH 4 to 9). Regarding the charged molecule at pH 7 the log Koc was estimated to be 2.29 (Koc = 193) following the method of Franco & Trapp (2008) and using the pKa of 3.79 (from SPARC v4.6 calculation).

Therefore, adsorption to solid soil phase is not expected.