Abstract: A face mask comprising a filter material being a fibrous substrate, especially non-woven polypropylene or polyester, having an acidic polymer, especially of the Carbopol or Gantrez type, deposited on the fibres. The mask has an anti-viral activity against inhaled or exhaled air. A filter material suitable for such a mask, and a process for making it are also described.

Abstract: Wastewater treatment systems, methods and apparatus for polishing a wastewater stream comprising a plurality of contaminants are provided. One system includes a vessel containing a plurality of natural media filtration agents selected to remove selected ones of the plurality of contaminants from the wastewater stream. In one embodiment, the vessel includes a bed of bauxite residue and at least one other natural media filtration agent. In another embodiment, the vessel includes a bed of compost and at least one other natural media filtration agent. The vessel includes a wastewater inlet that is in fluid communication with one or more of the natural media filtration agents. The vessel includes a wastewater outlet that is in fluid communication with one or more of the natural media filtration agents.