Phosphorodithioic acid, mixed O,O-bis(2-ethylhexyl and iso-Bu and pentyl) esters, zinc salts

Endpoint summary

Description of key information

Short description of key information on bioaccumulation potential result: 
.  The physicochemical properties, toxicity studies in animals, and QSAR predictions provide sufficient support in determining the ADME profile for the registered substance, and therefore may substitute for animal tests. 

Key value for chemical safety assessment

Bioaccumulation potential:

no bioaccumulation potential

Additional information

Physical-chemical properties of this substance were integrated with data from acute and repeated-dose toxicity studies and QSAR predictions to evaluate its toxicokinetic behavior. Absorption from the inhalation route was not evaluated due to the low vapor pressure of the substance. Absorption from the oral route was predicted to be possible, but slow and inefficient. Absorption from the dermal route, which is the route of primary interest for occupational exposures, is expected to be < 10% of the applied dose. Distribution is possible through the circulatory system, but the substance’s high molecular weight and lack of predicted protein binding indicate that distribution may be limited. Once distributed, the substance could potentially traverse cellular barriers and distribute to fatty tissue or distant organs other than site of exposures. However, there was no evidence of cumulative toxicity as would be manifested by an accumulation of this type of substances in tissues, and a similar substance has a low bioaccumulation factor. Metabolism of the systemically absorbed substance is expected to occur primarily in the liver,making the substance more soluble by oxidation and conjugation for eventual release into the urine or bile and into the gastrointestinal tract for elimination. Metabolism is also possible in the skin, by similar mechanisms. Acute and repeated-dose toxicity testing on the registered substance or analog substances did not indicate that the substances were transformed to toxic metabolites. If the metabolites are not assimilated into normal cellular metabolic pathways, they are expected to readily undergo routine renal and/or biliary excretion based the predicted structures. The physicochemical properties, toxicity studies in animals, and QSAR predictions provide sufficient support in determining the ADME profile for the registered substance, and therefore may substitute for animal tests.