Cosmetics containing nanoparticles — materials on a super-tiny scale — could be banned if there is a risk to human health, under legislation updated in the European Parliament.Any nanomaterials present have to be mentioned on the packaging. This means an insoluble or bio-resistant and intentionally manufactured material whose structure measures down to 1nm. At this scale, materials can show altered properties, for instance opaque becoming transparent or those which are normally stable provoking chemical changes at a nanoscale. The European Commission estimated in 2006 that about 5% of cosmetic products contained nanoparticles. The basic aim of the new regulation is to increase the safety of these products. The existing provisions with a phasing-out period for animal tests on cosmetic ingredients from now until 2013 are unaffected by the new regulation. The use of substances which are carcinogenic, mutagenic or toxic for reproduction is basically forbidden, but they can be used in exceptional cases under strict conditions.