“…Under oxic conditions, crystallized or amorphous Fe(III) mineral phases are able to incorporate or scavenge toxic trace elements such as As, Cr, Cd or Pb (Bousserrhine et al, 1999;Morin et al, 1999Morin et al, , 2002Brown and Sturchio, 2002;Bonneville et al, 2004;Morin and Calas, 2006). Secondary Fe(II)-Fe(III)-containing minerals, such as green rusts and magnetite (Lovley et al, 1987;Ona-Nguema et al, 2002, 2004Zachara et al, 2002;Glasauer et al, Chemical Geology 406 (2015) [34][35][36][37][38][39][40][41][42][43][44] 2003; Zegeye et al, 2005), have been shown to scavenge trace elements (e.g., Cooper et al, 2000;Coker et al, 2006;Root et al, 2007;Wang et al, 2008;Ona-Nguema et al, 2009). Among the trace metals, arsenic (As) is strongly adsorbed onto Fe-oxides (Manning et al, 1998;Raven et al, 1998;Dixit and Hering, 2003), which are probably the largest carriers of As in aquifers and soils (Morin et al, 2002;Cancès et al, 2005Cancès et al, , 2008; Morin and Calas, 2006).…”