Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

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Additional information

Polysulfides, di-tert-dodecyl is not readily biodegradable according to OECD guideline criteria and is expected to strongly sorb on sediment particles based on experimental Koc value.

Polysulfides, di-tert-dodecyl is therefore not expected to remain in the water column and on this basis notifier proposed to improve biodegradation knowledge by carrying out simulation test on sediment only.

Determination of the hydrolysis rate for polysulfides, di-tert-dodecyl is not achievable based on its determined extremely low water solubility and its lack of hydrolysable groups in its structure.

The Henry's Law constant for polysulfides, di-tert-dodecyl is 1.177 Pa/m3-mol, which indicates that it is expected to volatilize significantly from the aquatic environment.

The distribution of polysulfides, di-tert-dodecyl in the environment through an emission to water letting to expect a partitioning to sediment from the water column an OECD 308 compliant study aiming to estimate the biodegradation in water/sediment systems has been done further to a testing proposal agreed by ECHA. The results of this study show a degradation of the substance with a half-life of about 169 days. During the course of the study it was investigated if tert-dodecyl mercaptan (TDM), raw material used for synthesis of polysulfides, di-tert-dodecyl could be produced as a metabolite, for which experimental information is available concerning bioaccumulation and toxicity to sediment organisms. As this was not the case, it has been proposed to investigate these two properties through a further testing proposal. Both studies have now been done. It is shown that no bioaccumulation to fish occurs and the sediment toxicity test has permitted a refinement of the PNECsediment.