Completed Task Force

Low-dose interactions

Health Sciences Manager Christa Hennes

Administrative Assistant Christine Yannakas

The task force published its findings in July 2012 as Technical Report No. 115; "Effects of Chemical Co-exposures at Doses Relevant for Human Safety Assessments"

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Much attention is being given to the so called “cocktail effect‘ which is hypothesised to occur due to simultaneous exposure to low levels of environmental chemicals. According to this theory, unexpected effects can occur due to interaction in the body between these chemicals even though the levels could be below the threshold of toxicity for the individual chemicals or their breakdown products. It is claimed that these interactions at low-dose levels may be greater than additive.

Terms of reference

  1. Review the scientific literature on interactions between chemicals at low doses, i.e. particularly those occurring below a toxicological point of departure of the individual chemicals.
  2. Evaluate whether the evidence on interactions at low doses demonstrates toxicologically relevant effects and determine whether there are any associations with specific modes of action.
  3. Look at the evidence of chemical interactions and comment on the likelihood of those being important in the context of environmental exposures.
  4. Evaluate the adequacy of current human safety risk assessment practice in light of the conclusions of the above.

The task force will write a technical report and a publication for the peer-reviewed literature, if feasible. The draft report should be available by mid 2011. A workshop to discuss the outcome with a wider audience may be proposed.