Registration Dossier

Administrative data

Link to relevant study record(s)

Description of key information

No specific study was performed on absorption, distribution, metabolism and/or excretion (ADME) of WS400505. Its systemic availability after topical or oral administration is expected to be very limited based on its relatively high molecular weight, low water solubility and high lipohilicity restricting the bioavailability of the substance. Availability of WS400505 under a vapour state is unlikely, because of its low vapour pressure. 
Based on the available data the bioacumulation potential cannot be judged. However, based on the very low dermal, oral and inhalative bioavailability of the substance and absence of adverse effects in all toxicological tests performed a low bioaccumulation potential (if any) is expected.

Key value for chemical safety assessment

Additional information

No specific study was performed on absorption, distribution, metabolism and/or excretion (ADME) of WS400505. Predictions on the toxicokinetic behaviour were made based on physical-chemical properties and information from toxicological studies.

WS400505 is a mono-constituent substance with a purity of > 99% (w/w). The substance is a saturated C41compound with the molecular formula C41H84N4O2. The substance contains two urea bonds the rest being two saturated C18n-alkyl chains and a propyl chain between the two urea groups. The following data on physical chemical properties of WS400505 are the basis for this toxicokinetics assessment.

- Molecular weight: 665 Da
- Water solubility: < 1 mg/l (determined); 3 x 10-12mg/l (calculated by US EPA WSKOWWIN)
- Melting point: 137°-168°C; substance decomposes before boiling
- Octanol/water partition coefficient: log Pow> 6 (determined); log Pow= 16 (calculated by US EPA KOWWIN)
- Vapour pressure: 2 x 10-4Pa (determined)

In all toxicological tests performed with WS400505 according to Annexes VII and VIII of the REACH Regulation no adverse effects were observed up to the highest doses required to be tested according to the relevant guidelines.

The ECHA “Guidance on information requirements and chemical safety assessment Chapter R.7c: Endpoint specific guidance, 2014” document provides guidance, which physico-chemical properties commonly determine dermal, oral, and inhalatory absorption of substances.

Bioavailability of WS400505 in general is expected to be very limited, because of the relatively high molecular weight, very low water solubility and high lipohilicity of the substance.

Accordingly, systemic availability of WS400505 after topical administration is expected to be very limited.

Also systemic availability of WS400505 after oral administration is expected to be very limited. In toxicity studies with single or repeated oral exposure no adverse effects were observed.

Availability of WS400505 under a vapour state is unlikely, because of its low vapour pressure.

Based on the available data on WS400505 the bioacumulation potential cannot be judged. However, based on the physical-chemical properties systemic availability of WS400505 via dermal, oral and inhalation exposure is expected to be very low. Also the bioaccumulation potential is expected to be very low based on the relatively high molecular weight and the very high octanol/water partition coefficient of the substance.

 

 Conclusion

While toxicokinetic data is not available on WS400505, based on the properties of the substance and based on the favourable toxicological testing results WS400505 is expected to be hardly bioavailable. Bioaccumulation is not expected. Further information on distribution, metabolism or excretion is not available.