Environmentally Friendly Zero Waste Cosmetics with Low Biological and Chemical Oxygen Demand

Cosmetics; once they enter the body, they can be metabolised and re-enter the environment through sweat, urine or faeces; therefore, disposal of these waste products using conventional methods is not always possible. Biochemical oxygen demand (BOD), a bioanalytical method, is used to interpret the biodegradability capacity of products at treatment plants and to assess the effectiveness of treatment. BOD is an indicator that reflects the amount of organically easily degradable compounds and is widely used in assessing water quality; in practice, it is usually expressed in mg O2/L. The inability to remove non-metabolised compounds during wastewater treatment and the effects of pollutants, particularly on air, water, and soil, can seriously threaten living organisms and natural resources in the long term. The aim of this study is to reduce the potential harm of chemicals in cosmetic products, prevent environmental pollution from packaging and contents, and minimise problems arising from their return to living organisms through environmental cycles. In this study, the aforementioned risks will be addressed preventively through in silico modelling and in vitro validation prior to use, during the development process of natural-based and zero-waste products, rather than after the use of cosmetic products. By adopting a zero-waste approach, efficiency and performance increase, while costs decrease and environmental risks are reduced through the prevention of waste. The results obtained are expected to shed light on the effects of different formulations associated with chemical risks on environmental sustainability (e.g., possible changes in carbon footprint) and contribute to the development of new methods in zero-waste cosmetics research.