A simple method was developed to synthesize composites containing cellulose (CEL) chitosan (CS), keratin (KER) (from wool, hair and chicken feather) and metal nanoparticles including silver, gold and copper oxide nanoparticles (AgNPs, AuNPs and CuONPs). In this method, butylmethylimmidazolium chloride ([BMIm⁺Cl^-]), a simple ionic liquid, was used as the sole solvent and metal salts such as silver chloride, HAuCl₄ or Copper oxide was added to the [BMIm⁺Cl^-] solution during the dissolution process. The metal salts in the composites were completely converted to metallic nanoparticles (Ag⁰NPs, Au⁰NPS or CuONPs) by reducing it with NaBH_4. FTIR, XRD and SEM results confirm that CEL, CS and KER remain chemically intact and homogeneously distributed in the composites, and that the Ag⁰NPs, Au⁰NPs or CuONPs in the composites is homogeneously distributed throughout the composites. All composites were found to exhibit excellent adsorbent for pollutants (endocrine disruptors, heavy metal ions) and antibacterial activity against many bacteria and fungi including Escherichia coli, Staphylococus aureus, Pseudomonas aeruginosa, methicillin resistant Staphylococus aureus (MRSA), vancomycin resistant Enterococus faecalis (VRE) and Candida Albicans. The antibacterial activity of both composites increases with the content of the nanoparticles in the composites. All nanoparticles composites were found to be toxic to human fibroblasts at higher concentration (e.g., >0.72 mmol for Ag⁰NPs). As expected, by lowering concentration of the NPs, (e.g., Ag⁰NPs concentration to <0.48 mmol), all three nanoparticle composites can be made biocompatible while still retaining their pollutant adsorber and antimicrobial activity. These results together with our previous finding that [CEL+CS+KER] composites can be used for controlled delivery of drugs (e.g. Ciprofloxacin) clearly indicate that the silver, gold and copper oxide nanoparticle composites possess all required properties for successfully used as dressing to treat chronic ulcerous infected wounds and to purify drinking water.