... .(3)Sulfate, as SO4: 0.005% max.(4)Iron, as Fe: 0.002% max.(5)Arsenic, as As: 0.005% max.(6)Heavy metal, as Pb: 0 ... .(3)Sulfate, as SO4: 0.005% max.(4)Iron, as Fe: 0.002% max.(5)Arsenic, as As: 0.0001% max.(6)Fluoride, as F: 0 ... .001% max.(7)Heavy metal, as Pb: 0.001% max ...