The concentration (CNM) of TiO2 in sunscreen products is in the range of 2–10 % (Mueller and Nowack 2008; Boxall et al. 2007; Gottschalk et al. 2010), meaning that globally 14.3–143 Mg of nano-TiO2 was used in sunscreens in 2008 (Table 3). In the same year, the global production of nanoTiO2 was in the order of 5,000 Mg year-1 (Mueller and Nowack 2008), 0.3–3 % of which was thus used in sunscreens.