October 15, 2010 by wca Staff


At wca we have used QSARs and read-across extensively under REACH, so we were naturally interested when on 23rd – 24th of September the European Chemicals Agency (ECHA) hosted a workshop entitled “Dealing with Uncertainty of Non-Test Methods under REACH”. Representatives from several organisations involved in REACH, including national regulatory agencies and industry, shared their experiences and expectations when using non-testing methods within the REACH framework.

The presentations addressed Quantitative Structure Activity Relationships (QSARs), read-across (inferring a property of one chemical from that of a similar chemical) and categorisation (the collation of groups of chemicals expected to have similar properties).

The Danish EPA, who are European leaders in QSAR implementation emphasised the need to check that QSARs are of good quality (with good documentation) prior to use. Other national agencies made similar comments, with a concern that QSARs are being produced and used with only low and inadequate levels of supporting documentation.

Industry representatives described how they had used non-testing methods – mostly for less complex endpoints where confidence in results can be high. At least one presenter noted that the predictive ability of well-applied non-testing methods can be close to that of experimental methods.

ECHA’s presentation noted concerns about insufficient documentation for some QSARs, and that some read-across is based solely on “wishful thinking” rather than robust scientific justification. However the overall tone of the presentations was generally positive about advancing the use of non-testing methods under REACH.

The presentations from the meeting can be found on the ECHA website.

If you are interested in the use of non-testing information the following resources may be useful to you:

  • ECHA’s new information toolkit which gives “practical information and tools in relation to help in using of existing information and non-test methods (i.e. predictions) as a first step to meeting REACH information requirements”
  • wca’s spreadsheet tool for advice on QSAR use (to be published online next week).