Lose keratin fibers have been used to create absorbents for metal ion removal. Untreated keratin fibers exhibit low levels of metal ion absorptions. For example, when untreated feather fiber (0.5 cm in length) was used as an absorbent, Pb2+ removal was very low, the maximum removal was in the range of 0.8 to 8.3 mg/g with contact time of 5 h62. untreated cleaned human hair (0.1–1.0 cm) absorbed low levels of Cu2+ (35µg/g), Zn2+(10 µg/g), Mn2+ (1.1 µg/g) and As3+ (0.1 µg/g) from aqueous solutions with initial metal ion concentration of 0.3 ppm63. In general, with increasing initial metal ion concentration, the amount of absorbed metal ion increased. For example, when 100 ppm Zn2+ solution was used, the maximum sorption capacity of the ion was found to be 1.5 mg/g of cleaned chicken feather64.