Zinc bis(2-ethylhexanoate)

Endpoint summary

Description of key information

No repeated dose toxicity study with zinc bis(2-ethylhexanoate) is available. In the assessment of toxicity of zinc bis(2-ethylhexanoate), read-across to the assessment entities zinc and 2-ethylhexanoic acid is applied since the ions of zinc bis(2-ethylhexanoate) determine its toxicity in biological compartments.

In relevant and reliable repeated dose toxicity studies for both moieties of zinc bis(2-ethylhexanoate), there were no toxicological findings reported that would justify a classification for specific target organ toxicity with repeated exposure.

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Repeated dose toxicity: inhalation - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Repeated dose toxicity

Existing data on the repeated dose toxicity of the two moieties of zinc bis(2-ethylhexanoate) are detailed below.

Table: Summary of repeated dose toxicity data of the zinc bis(2-ethylhexanoate) and the assessment entities.

	(slightly soluble) zinc substances	2-ethylhexanoic acid (CAS# 149-57-5)	Zinc bis(2-ethylhexanoate) (CAS# 136-53-8)
Repeated dose oral toxicity	NOAEL(human data)= 0.83 mg Zn/kg bw/day*	NOAEL(rat;90d)= 300 mg/kg bw/day   NOAEL(mice;90d)= 200 mg/kg bw/day	no data

* Identified as most sensitive endpoint in the registration dossier for zinc, thus has been used for the DNEL derivation of this substance.

 

Zinc

From studies in which humans were supplemented with zinc (as zinc gluconate)it was concludedthat women are more sensitive to the effects of high zinc intake and that a dose of 50 mg Zn/day is the human NOAEL. This corresponds to a daily exposure of 0.83 mg Zn/kg bw. At the LOAEL of 150 mg Zn/day, clinical signs and indications for disturbance of copper homeostasis have been observed. Studies conducted on animals are not discussed here, since information on human experience are considered of higher relevance for risk assessment purposes and should take precedence over animal studies.For further information on the toxicity of zinc, please refer to the relevant assessment entity sections in the IUCLID and CSR.

 

2-Ethylhexanoic acid

In a 90-day repeated dose toxicity study in rats and mice with 2-ethylhexanoic acid, adiet containing 0.5% 2-ethylhexanoic acid caused no adverse effect in rats in a 13 week feeding study (dose levels were 0, 0.1, 0.5, or 1.5%, calculated NOAEL ca. 300 mg/kg bw/day). No adverse effect was observed in mice receiving a diet containing 0.5 % 2-ethylhexanoic acid in a 13 week feeding study (dose levels were 0, 0.1, 0.5, or 1.5%). The NOAEL was calculated to be 200 mg/kg bw/day. Both NOAELs were based on reduced food consumption and a decreased rate of body weight gain in the high dose groups. For further information on the toxicity of 2-ethylhexanoic acid, please refer to the relevant assessment entity sections in the IUCLID and CSR.

 

Zinc bis(2-ethylhexanoate)

Since no repeated dose toxicity study is available specifically for zinc bis(2-ethylhexanoate), information on the assessment entities zinc and 2-ethylhexanoic acid will be used for the hazard assessment and when applicable for the risk characterisation of zinc bis(2-ethylhexanoate). For the purpose of hazard assessment of zinc bis(2-ethylhexanoate), the point of departure for the most sensitive endpoint of each assessment entities will be used for the DNEL derivation. Zinc has been identified as the moiety with the lowest NOAEL and the NOAEL of 0.83 mg Zn/kg bw/day obtained from human data (repeated dose) will be used.

Justification for classification or non-classification

In relevant and reliable repeated dose toxicity studies for both moieties of zinc bis(2-ethylhexanoate), there were no toxicological findings reported that would justify a classification for specific target organ toxicity with repeated exposure. Hence, no classification for zinc bis(2-ethylhexanoate) as STOT, RE via the oral route is required.