Potassium sodium tartrate

Endpoint summary

Description of key information

Short description of key information on bioaccumulation potential result:

1. the absorption and excretion of L(+)-tartaric acid is rapid.

2. the mainly distribution of tartaric acid after oral dosing is in the gastrointestinal tract, liver, kidneys and bone in rats.

3. part of the substance is metabolised by gut flora, part is metabolised by tissue enzyme, and major is excretion unchanged by urine.

4.  the absorption rates for DL-tartrate through oral administration in rat and human are 81 % and 18 %, respectively.

Key value for chemical safety assessment

Bioaccumulation potential:

no bioaccumulation potential

Additional information

First, in study Chasseaud LF et all (1977), it indicated that, in rat, oral dosing of L(+) tartrate was extensively absorbed and excreted very rapidly (excretion of radioactivity in the urine was almost completed within 12 h and in the expired air within 24 h). This result is also confirmed by studies Down WH et all (1977), Chadwick VS (1978) and Gry J & Larsen JG (1978). So we can conclude that the absorption and excretion of L(+)-tartaric acid is rapid.

Second, in study Down WH et all (1977), it is revealed that at 3 h after the last dose of L(+)-tartrate, the radioactivity was mainly present in the gastrointestinal tract, liver, kidneys and bone, which means that tartrate or its metabolites distribute in those organs & tissues.

 

Third, from studies Chasseaud LF et all (1977) and Chadwick VS (1978), we can find that tartaric acid can be metabolised by the gut flora, but also can be absorbed extensively and partly metabolised into CO2 by tissue enzymes. All the studies here indicated that absorbed tartaric acid is mainly excreted unchanged by urine, and this may be the reason of subsequent nephrotoxicity.

 

Forth, from study Gry J & Larsen JG (1978), we can find that the toxicokinetics profiles vary in different species. So the toxicokinetics profiles in human might not be similar to that in rat or other species. In study Chadwick VS (1978), the different toxicokinetics profiles in human and rat were compared. It is indicated that the excretion of tartrate in feces is very limited both in rat and human, which means most of the dosed tartaric acid are absorbed or metabolised in gastrointestinal systems. The absorption rate for DL-tartrate in human is estimated around18 %, while that value is 81 % in rats. Such values will be used in the calculation of relevant DNELs.

 

It needs to be emphasised here that the test material information, such as the purity, was not clearly described in those published literatures. But as mechanism studied researches, it is reasonably considered that such test material is relatively pure substances.

 

Furthermore, in studies Chasseaud LF et all (1977), Down WH et all (1977), Chadwick VS (1978), the test materials used were sodium salts of tartaric acid. Those studies here can be served as read across studies, because the basic chemical structures of these chemicals are the same.