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Description of key information

Experimental toxicokinetic studies were not available. However, as per REACH guidance document R7.C (May 2008), information on absorption, distribution, metabolism and excretion may be deduced from the physicochemical properties. Indeed, DETU seems to be well absorbed by oral and dermal route, then well distributes in the body and probably excreted in urines.

Key value for chemical safety assessment

Additional information

The following remarks on the toxicokinetics of DETU are based on the available studies. Experimental toxicokinetic studies were not available. However, as per REACH guidance document R7.C (May 2008), information on absorption, distribution, metabolism and excretion may be deduced from the physicochemical properties, including:

-Molecular weight: 132.23 g/mol

-Water solubility: 42 g/L (20°C), DETU is highly soluble in water.

-Partition coefficient Log Kow: 0.57

-Vapour pressure: 0.00065 Pa (25°C)

 

 

ABSORPTION

The physicochemical characteristics of DETU (log Kow 0.57) and the molecular mass (132.23 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 data acute oral toxicity (LD50 = 930 mg/kg bw in mice).

Molecular weight (near to 100 g/mol) is in ranges which favour dermal absorption. This assumption of a dermal absorption is confirmed by the skin sensitisation data as DETU is a skin sensitizer.

 

DISTRIBUTION and METABOLISM

As a small molecule a wide distribution of DETU is expected. This assumption is confirmed by the changes shown in the repeated dose toxicity studies following oral application: effects on thyroid were specific to the oral administration of DETU in rats.

No specific information was found on metabolism of DETU.

 

EXCRETION

DETU 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.