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Residues from footwear roughing and carding operations represent 5-15% (w/w) of the solid wastes generated by shoe-making companies. These wastes are mainly composed by chromium tanned leather and sole materials, and are mostly land filled. Sometimes leaching tests show these wastes as hazardous due to chromium in the leachate. This work aims at a more sustainable option for these wastes by recycling them in styrene butadiene rubber (SBR) and acrylonitrile butadiene rubber (NBR). Thus, they were charged with: (i) 1 mm leather waste fibers in the range of 10-25 parts per hundred parts of rubber (phr); and (ii) leather and soles industrial carding and roughing wastes in the range of 20-100 phr. The leather waste fibers-rubber composites tear strength is increased till 25 phr and both tension and elongation at break decrease within the acceptable range till 12.5 phr for SBR and 15 phr for NBR. In the case of leather and sole carding and roughing wastes, composites tear strength increases till 100 phr, and tension and elongation decrease within the acceptable range till 20 phr. The composite materi-

The production of natural and synthetic rubber / waste -EVA (Ethylene-Vinyl Acetate) composites was performed using natural rubber, styrene-butadiene rubber or acrylonitrile-butadiene rubber and 10 -20 parts per hundred rubber (phr) of waste.Several physical and mechanical properties of the composites were further determined according to the requirements of the footwear sector. Rheometry and aging tests were also performed. The effects observed on the crosslinking formation during vulcanization of each composite were negligible. The flexion, density, hardness and abrasion of all composites, produced at a laboratory (10 -20 phr) and industrial scale (20 phr), were not significantly affected by the addition of waste. The tear strength and the tensile strength were the most affected properties, namely for the Natural Rubber/Waste -EVA composites, where EVA acted as filler (tear strength> 13 N mm -1 , breaking load > 15MPa). The study confirms the possibility of a sustainable application of EVA-waste in the footwear industry through the production of eco-composites.