The perspective of the BioNaD project will focus to demonstrate and promote the use of innovative dyes (or colorants) for the leather industry, with the goals of demonstrating new and environmentally friendly substances for a sustainable development. The goal of the project will be pursued specifically, by demonstrating the reliability and efficacy of an original, publicly known and already validated concept: the process of “naturalization”, that is the chemical transformation of water insoluble dyes into water-soluble species, capable of replacing the actual commercial dyes. Technically, the naturalization is achieved by linking chemically a synthetic dye to the sugar lactose, creating a new and independent chemical species possessing unique properties. One objective of the proposal is to reduced significantly (90%), or possibly eliminate (100%), the amount of chemicals associated to the use of dyes for leather. Commercial dyes contain auxiliary chemicals in the range of 10 – 200% on the weight of the dye, impacting heavily on the purification processes of dyeing effluents. Naturalised dyes do not contain any of those species. Another purpose of the project is to use lactose, a by-product of the dairy industry, for the manufacture of naturalised dyes. It is estimated that about 210-220 L of milk serum will be needed to produce the relevant quantity of lactose (ca.9Kg) to achieve the equivalent of 6 Kg of a naturalised dye for processing 100 leathers of medium weight (ca. 2 Kg). On a projected global scale this means that about 8-9% of the total amount of milk serum disposed of in the environment globally (ca. 34 million Ton per year) may be valuable for the production of naturalised dyes. Also, these dyes made of lactose are degraded by common strains of E. coli bacteria without the release of toxic chemicals. Therefore, dyeing effluents (about 0.7 m3 for 100 leathers processed) consisting only of water and residual naturalised dyes, may be reused in the range of 50-75% of the volume for successive dyeing cycles. The source of milk serum (whey) is milk obtained primarily from cows. Whey is a by‑product of the manufacture of cheese and generally, it is further processed to obtain lactose for the food and pharmaceutical industry. Whey enters into the synthesis of naturalised dyes indirectly, since it is the source of lactose, which is the actual chemical species used for the manufacture of naturalised dyes. Therefore, synthetic chemists will purchase lactose from the relevant suppliers and will use lactose as raw material to building up the relevant chemical species useful for the naturalization process: that is, the chemical transformation of water insoluble dyes into water-soluble colorants without the need of any auxiliary chemicals, which are present in commercial preparations of dyes. The added values of the BioNaD project will be the care and protection of the environment through the reduction of the environmental impact of the dyeing processes. This goal will be achieved by combining three concepts in a synergistic action: in the first instance, the use of naturalized dyes will allow to dye leather in the absence of chemical additives (commonly found in traditional dyes) which constitute a serious source of pollutants; secondly, the involvement of lactose in the chemical structure of the dyes will contribute to reduce markedly the environmental impact of milk serum (which is the source of lactose) and thirdly, the device of biotech processes to treat dye containing wastewaters will enable the recycle of water. Moreover this latter aspect will demonstrate the activity of common bacteria such as Escherichia coli on dyeing effluents. This project aims at demonstrating also tools and methods for best water management in consuming industries to significantly reduce the use of water. The sustainability of the project will be evaluated through the measurement of Life Cycle Assessment (LCA) one of the most widely used tools to evaluate the impacts of products and production processes across their entire lifespan.