The European Commission (EC) is seeking comments on a scientific paper regarding the toxicity and assessment of chemical mixtures prepared by European Union scientific committees that focus on consumer safety, health, environmental risks, and emerging and newly identified health risks.

Among the paper’s conclusions are (i) “Chemicals with common modes of action may act jointly to produce combination effects that are larger than the effects of each mixture component applied singly”; (ii) “For chemicals with different modes of action (independently acting), no robust evidence is available that exposure to a mixture of such substances is of health concern if the individual chemicals are present at or below their zero effect levels”; and (iii) For chemicals that interact, “interactions … usually occur at medium or high-dose levels …” Some chemical mixtures are addressed by EC Regulation No. 1907/2006 on the registration, evaluation and authorization of chemicals (REACH). The EC requests comments on the paper by September 9, 2011.