Research
A decision tree for assessing effects from exposures to multiple substances
1 The Dow Chemical Company, Toxicology and Environmental Research and Consulting, 1803 Building, Midland MI 48674, USA
2 Bayer Aktiengesellschaft, Corporate Centre, BAG-E&S-SER, Leverkusen, K 9, Germany
3 Syngenta, Jealott’s Hill International Research Centre, Bracknell, Berkshire, RG42 6EY, United Kingdom
4 Shell International BV, PO Box 162, 2501 AN, The Hague, The Netherlands
5 Ecototox Centre, Oekotoxzentrum Eawag/-EPFL, Swiss Centre for Applied Ecotoxicology, Überlandstrasse 133, Postfach 611 CH-8600, Dübendorf, Switzerland
6 BASF, SE, Speyerer Str. 2, 67117, Limburgerhof, Germany
7 Procter and Gamble, Temselaan 100, 1853, Strombeek-Bever, Belgium
Environmental Sciences Europe 2012, 24:26 doi:10.1186/2190-4715-24-26
Published: 4 October 2012Abstract
Background
The Cefic Mixtures Industry Ad-hoc Team (MIAT) has investigated how risks from combined exposures can be effectively identified and managed using concepts proposed in recent regulatory guidance, new advances in risk assessment, and lessons learned from a Cefic-sponsored case study of mixture exposures.
Results
A series of tools were created that include: a decision tree, a system for grouping exposures, and a graphical tool (the MCR-HI plot). The decision tree allows the division of combined exposures into different groups, exposures where one or more individual components are a concern, exposures that are of low concern, and exposures that are a concern for combined effects but not for the effects of individual chemicals. These tools efficiently use available data, identify critical data gaps for combined assessments, and prioritize which chemicals require detailed toxicity information. The tools can be used to address multiple human health endpoints and ecological effects.
Conclusion
The tools provide a useful approach for assessing risks associated with combined exposures to multiple chemicals.



