Article

OECD Revises QSAR toolbox User Manual for Grouping of Chemicals for Aquatic Toxicity Assessment

Posted on: December 7, 2013

By Martina Schneider

The Quantitative Structure Activity Relationship (QSAR) Toolbox is a free software application provided by the Organization for Economic Co-operation and Development (OECD) for assessing the hazards of chemicals.  The Toolbox includes data and software tools from various sources and is able to group chemicals into categories and allows the filling of data gaps by mechanistic comparisons.

In addition, the OECD recently updated parts of its training material to correlate with the current version 3.1of the Toolbox.  This includes the user manual “Strategies for grouping chemicals to fill data gaps to assess acute aquatic toxicity endpoints.”

The document contains an introduction about the tools and database available for aquatic toxicity assessments and provides guidance on its use.  Acute aquatic toxicity endpoints are the biggest group of data included in the toolbox, and integrated databases are from multiple sources including, but not limited to, the ECETOC Aquatic Toxicity database, Aquatic US-EPA ECOTOX and Aquatic Japan MoE.

In addition to the data, there are five primary profilers containing structural alerts associated with toxicity based on an analysis of aquatic toxicological data.  The profilers define the potential mechanismmode of action of the target chemical.  The manual introduces the different profilers and explain the best use of the results with the help of a working example.

Finally, the manual describes the data gap filling via trend analysis and read across; it also presents a general strategy to fill data gaps.  Several screenshots from the program facilitate the understanding.

The software is intended for use by government agencies and stakeholders to address tox and ecotox data gaps for hazard and risk assessment of chemicals.  The manual will be more helpful for users who already have some experience with the workflow of the Toolbox.  It is not recommended for beginners.

The updated version of the manual is available from the OECD website: http://www.oecd.org/env/ehs/risk-assessment/Acute%20aquatic%20toxicity.pdf