Environmental implications and hidden costs of artisanal spirulina (Arthrospira platensis) production and consumption

Abstract

This study aims to assess for the first time the environmental interactions of artisanal spirulina production and consumption, addressing a holistic approach by including the nutritional properties within the assessment and an economic analysis. To do so, life cycle assessment is conducted defining the system boundaries from cradle to consumer and two functional units: mass-based (1 kg of product) and nutrient-based (Spanish Nutrient Rich (super)Food 9.2 score). Afterwards, the monetization of the environmental impacts using the ?eco-cost? method and the internalization of externalities to estimate the real cost of spirulina is performed. The purely environmental analysis identifies cultivation as the main hotspot of the product system, reporting a total average carbon footprint of 3.5 kg CO2 eq./kg, while together with the nutritional model, it reveals the potential of spirulina supplements by reducing the impacts as consequence of its rich nutritional profile. In monetary terms, the internalization of external costs linked to the impacts are trivial compared to the selling price of spirulina; only 3.6€ per kg of spirulina should be invested to avoid the negative effects of its production, while its market price sums up to 217€/kg. This value falls drastically by including the nutritional index in the evaluation, as well as varies significantly when modifying the monetization method, which constitutes a constraint at the same time that a challenge for future studies.