Reference substance information is stored in the Reference substance inventory. This inventory is the place where Reference substances can be created, updated, exported or deleted. For the import of Reference substances see chapter D.11.9 Importing a Reference substance. The Reference substance inventory is directly maintained by the user, in his local IUCLID installation.
A Substance dataset needs to be associated to at least one Reference substance, since it is the only way to unequivocally identify the substance to which the dataset relates. To associate a Reference substance to a Substance or Mixture dataset, a link has to be created within the dataset itself. When this relationship is established, the Reference substance information is virtually part of the dataset, but it is always physically stored in the local Reference substance inventory.
When datasets are exchanged by using the import/export functionality (see chapter D.14 Import (Import data from other IUCLID 5 systems)), the associated Reference substance(s) are included in the import/export file. In case of import, the receiver of the Substance or Mixture dataset has the choice to "update" (overwrite) his own Reference substance inventory with the "new" Reference substance information contained in the import file.
The Import procedure issues a warning if an imported element already exists in the target database (indicating: Identical, Older or Newer than existing). If a Reference substance is not already present, it will be added to the local Reference substance inventory.
Each Reference substance can be linked to an unlimited number of Substance or Mixture datasets. For updating the information in a Reference substance, the user can open the Reference substance inventory, search for the Reference substance and update it. The modifications will impact every single dataset linked to that Reference substance.
The Reference substance itself is not physically part of the substance dataset but belongs to the local Reference substance inventory.
In summary, the Reference substance inventory gives the possibility:
To use the same information for the chemical identity, anytime needed, avoiding to re-type it.
To keep information used for the substance identification always updated in all associated datasets.
The European Commission has prepared ca. 70,000 pre-filled Reference substances. The data used to fill in this information originates from own information completed with generated substance identification data. Generating and providing these pre-filled Reference substances was done to improve data quality, minimise data entry and enhance data exchange possibilities. Because data are generated, errors might occur although quality checks have been done e.g. by cross-linking the information with other inventories than EINECS. Nevertheless, the content of the Reference substance used in a Substance or Mixture dataset remains under the responsibility of the owner's local IUCLID 5 installation.
The pre-defined Reference substances can be downloaded from the IUCLID web site. It is possible to download all of part of them and save the download files in your computer (as IUCLID 5 import file *.i5z). With the standard procedure (see chapter D.14 Import (Import data from other IUCLID 5 systems)), the downloaded Reference substance(s) then can be imported into your IUCLID installation. The imported Reference substances can be edited if deemed necessary.
A pre-filled Reference substance provided by the European Commission can be downloaded from the IUCLID web site and imported following the installation wizard (see chapter C.2 Starting IUCLID 5: First steps wizard). In the case of more than one Reference substances the bulk import function can be used (see chapter D.14.10 Bulk import feature).