“…Important samples were arsenic [39,41], mercury [40], lead [38,43,52,56,67,68,70,[72][73][74][75][76], copper [31,32,64], nickel [64] vanadium [63,64], manganese [49,69,55], silver [48,50,51], cobalt [45], zinc [36,77] and cadmium [29,58,66,67,73]. Somewhat outside the mainstream was an analytical procedure for nanoparticulate ferric oxide suspensions that play an important role in the environment [47].…”