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Description of key information

Key value for chemical safety assessment

Additional information

The following remarks on the toxicokinetics of DBTU are based on the available studies. Experimental toxicokinetic studies were not available. However, as per REACH guidance document R7.C (2014), information on absorption, distribution, metabolism and excretion may be deduced from the physical-chemical properties, including:

-Molecular weight: 188 g/mol

-Water solubility: 0.212 g/L (20°C)

-Partition coefficient Log Kow: 2.75 

 

ABSORPTION

The physical-chemical characteristics of DBTU (log Kow 2.75) and the molecular mass (188 g/mol) are in the range suggestive of absorption from the gastro-intestinal tract subsequent to oral ingestion (with a molecular weight below 500, and a log Kow between -1 and 4). This assumption of an oral absorption is confirmed by the acute oral toxicity study in which mortalities were observed at the dose of 2000 mg/kg bw.

Molecular weight (near to 200 g/mol) is in ranges which favour dermal absorption. This assumption of a dermal absorption is confirmed by the skin sensitisation data as DBTU is a skin sensitizer.

 

DISTRIBUTION and METABOLISM

As a small molecule a wide distribution of DBTU is expected.

No specific information was found on metabolism of DBTU.

 

EXCRETION

DBTU is probably excreted in the urine, because it is a water-soluble substance with a low molecular weight (below 300); and generally, they are conjugated metabolites from Phase II biotransformation.