TECHNOLOGY FOCUS - ENVIRONMENT - Preferred Materials : The fibrous proteins are collagen, keratin, casein or gelatine or substitutes such as feathers, hair, leather or leather-containing articles such as shoes and the chemicals used to treat them are Cr(III) sulfate, K Al sulfate, tannin, esters of phenolic carboxylic acids with sugars and/or other polyhydric alcohols, as well as other tanning materials. When granulated or shredded scrap shoes or other tanned leather articles (particle size below 20 mm) are used as the protein component, there is no need for the chemical modification step. The microorganisms are Pseudomonas putida, Pseudomonas spec., Acinetobacter calcoaaceticus, Nocardia spec., Corynebacterium spec., Candida lipolytica, Candida tropicalis, Rhodopseudomonas palustris and Rhodococcus spec..Preferred Process : The chemicals are used in a concentration in the protein modification reaction of 5-40 volume % and the reaction is at 20-70 degrees C and pH 3.0-7.5. Following the modification reaction, the microorganisms are immobilized on the protein granulate surfaces by spraying them on as an aqueous suspension. Breakdown of the oil in the oil-loaded materials after use can be accelerated by mixing with a nutrient and aerating the mixture.    TECHNOLOGY FOCUS - BIOLOGY - Preferred Materials : The fibrous proteins are collagen, keratin, casein or gelatine or substitutes such as feathers, hair, leather or leather-containing articles such as shoes and the chemicals used to treat them are Cr(III) sulfate, K Al sulfate, tannin, esters of phenolic carboxylic acids with sugars and/or other polyhydric alcohols, as well as other tanning materials. When granulated or shredded scrap shoes or other tanned leather articles (particle size below 20 mm) are used as the protein component, there is no need for the chemical modification step. The microorganisms are Pseudomonas putida, Pseudomonas spec., Acinetobacter calcoaaceticus, Nocardia spec., Corynebacterium spec., Candida lipolytica, Candida tropicalis, Rhodopseudomonas palustris and Rhodococcus spec.. Preferred Process : The chemicals are used in a concentration in the protein modification reaction of 5-40 volume % and the reaction is at 20-70 degrees C and pH 3.0-7.5. Following the modification reaction, the microorganisms are immobilized on the protein granulate surfaces by spraying them on as an aqueous suspension. Breakdown of the oil in the oil-loaded materials after use can be accelerated by mixing with a nutrient and aerating the mixture. EXAMPLE - An asphalt path covered with 1l of petroleum could be completely cleaned by spreading 300 g of an oil binder on it for 30 minutes and then sweeping clear, the binder having been obtained by shredding 500 kg scrap leather, magnetically removing metal components, cutting to below 5 mm particles and then spraying with an aqueous suspension of oil-degrading bacteria.