The German Ministry of the Environment (UBA) published a review of existing knowledge on the carcinogenic and mutagenic potential of nanoparticles. The report, which is intended to inform future regulatory measures, reviewed over 100 long term studies on different nanomaterials. Substances assessed include silicon dioxide, metals and carbon nanotubes. Silicon dioxide is used as an anti-slip agent in food contact printing inks, paper and board, rubbers and silicones, and authorized for use in plastic food contact articles under regulation EC 10/2011. Carbon black is also authorized under regulation EC 10/2011 and is additionally used in rubbers, silicones and printing inks intended for food contact. While the report’s authors found significant differences in toxicity of different nanomaterials, they considered that all nanomaterials cause inflammation and exhibit consistently higher toxicity than non-nanomaterials. The authors suggest the grouping of nanomaterials according to their potential to generate inflammation. Inflammation is considered a possible early event in cancer development. The report further suggests a preliminary lower observed effect level (LOAL) of 0.1 mg/m3 (exposure 24 h/d, 7 d/wk) to distinguish inert nanomaterials, such as carbon black, from nanomaterials with specific toxicity. The authors further assert that nanotubes should be regulated separately.