Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Toxicological information

Endpoint summary

Currently viewing:

Administrative data

Key value for chemical safety assessment

Additional information

Introduction to read-across matrix

A comprehensive data gap analysis was conducted for the entire substance portfolio of the Metal carboxylates REACH Consortium (MCRC), covering 10 metal carboxylates in total. This literature screening effort included:

 

  • all available proprietary studies from the Metal carboxylates REACH Consortium (MCRC)
  • detailed literature searches in online databases
  • screening of human health review articles
  • rigorous quality and reliability screening according to Klimisch criteria, where those criteria apply

 

During the literature search and data gap analysis it became obvious that the overall database on substance-specific human health hazard data for the metal carboxylates is too scant to cover all REACH endpoints. Therefore, the remaining data gaps had to be covered by either experimental testing or read-across from similar substances.

 

Selected endpoints for the human health hazard assessment are addressed by read-across, using a combination of data on the organic acid counterion and the metal (or one of its readily soluble salts). This way forward is acceptable, since metal carboxylates dissociate to the organic anion and the metal cation upon dissolution in aqueous media. No indications of complexation or masking of the metal ion through the organic acid were apparent during the water solubility tests (please refer to the water solubility data in section of the IUCLID and chapter of the CSR). Once the individual constituents of the metal carboxylate become bioavailable (i.e. in the acidic environment in the gastric passage or after phagocytosis by pulmonary macrophages), the “overall” toxicity of the dissociated metal carboxylate can be described by the toxicity of the “individual” constituents. Since synergistic effects are not expected for this group of metal carboxylates, the human health hazard assessment consists of an individual assessment of the metal cation and the organic anion.

 

The hazard information of the individual constituents was obtained from existing REACH registration dossiers via a license-to-use obtained by the lead registrant. These registration dossiers were submitted to ECHA in 2010 as full registration dossiers, and are thus considered to contain relevant and reliable information for all human health endpoints. All lead-registrant dossiers were checked for completeness and accepted by ECHA, i.e. a registration number was assigned.

 

Hexanoic acid, 2-ethyl-, zinc salt, basic is the zinc metal salt of 2-ethylhexanoic acid, which readily dissociates to the corresponding divalent zinc cation and 2-ethylhexanoic acid anions. The zinc cation and the 2-ethylhexanoic acid anion are considered to represent the overall toxicity of the hexanoic acid, 2-ethyl-, zinc salt, basic in a manner proportionate to the free acid and the metal (represented by one of its readily soluble salts). Based on the above information, unrestricted read-across is considered feasible and justified.

Although the term „constituent“ within the REACH context is defined as substance (also being part of a mixture), the term constituent within this hazard assessment is meant to describe either part of the metal carboxylate salt, i.e. anion or cation.

Genetic toxicity

Merely one genetic toxicity study with hexanoic acid, 2 -ethyl-, zinc salt, basic is available, thus the genetic toxicity will be addressed with existing data on the dissociation products as detailed in the table below.

 

Table: Summary of genetic toxicity data of the hexanoic acid, 2-ethyl-, zinc salt, basic and the individual constituents.

 

(slightly soluble) zinc substances

2-ethylhexanoic acid

(CAS# 149-57-5)

Hexanoic acid, 2-ethyl-, zinc salt, basic

(CAS# 85203-81-2)

In vitro gene mutation in bacteria

negative

(weight of evidence)

negative

negative

In vitro cytogenicity in mammalian cells or in vitro micronucleus test

negative

negative
(read-across)

In vitro gene mutation study in mammalian cells

negative

negative
(read-across)

 

Hexanoic acid, 2-ethyl-, zinc salt, basic is not expected to be genotoxic, since (i) a bacterial reverse mutation test has shown no mutagenic effect for this substance and (ii) the two constituents zinc and 2-ethylhexanoic acid have not shown gene mutation potential in bacteria and mammalian cells as well as in vitro clastogenicity in vitro. Thus, hexanoic acid, 2-ethyl-, zinc salt, basic is not to be classified according to regulation (EC) 1272/2008 as genetic toxicant. Further testing is not required. For further information on the toxicity of the individual constituents, please refer to the relevant sections in the IUCLID and CSR.

Justification for selection of genetic toxicity endpoint

Read-across information.

Short description of key information:

Hexanoic acid, 2-ethyl-, zinc salt, basic is not expected to be genotoxic.

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Hexanoic acid, 2-ethyl-, zinc salt, basic is not expected to be genotoxic, since (i) a bacterial reverse mutation test has shown no mutagenic effect for this substance and (ii) the two constituents zinc and 2-ethylhexanoic acid have not shown gene mutation potential in bacteria and mammalian cells as well as in vitro clastogenicity in vitro. Thus, hexanoic acid, 2-ethyl-, zinc salt, basic is not to be classified according to regulation (EC) 1272/2008 as genetic toxicant.

Furthermore, hexanoic acid, 2-ethyl-, zinc salt, basic is not to be classified according to Directive 67/548 EC as genetic toxicant.