Life cycle analysis of shea butter use in cosmetics: from parklands to product, low carbon opportunities

Shea butter is an ingredient of growing global importance in the multi-billion dollar cosmetic and confectionary markets. It does not share the same negative environmental impacts of fertilizer use and land use change as alternative vegetable oils and so has been considered an environmentally friendly substitute, yet little is known of its carbon footprint. A life cycle assessment (LCA) was undertaken to investigate the greenhouse gas (GHG) emissions of 1 kg of shea butter in cosmetic products. The LCA of the traditionally produced ingredient gave an emission value of 10.374 kgCO2eq per kg of shea butter in a finished cosmetic product. 75.4% of these were due to the burning of firewood in open hearths during the post-harvest processing (49.5%) and traditional extraction (25.9%) stages of the supply chain. Emissions were attributed using mass allocation to the co-products of the sheanut husk (33.8%) and kernel residue (30.7%) and had the effect of greatly reducing the perceived emissions of the shea butter highlighting the importance of finding useful functions for co-products. Shea production supports local economies and habitats and recommendations to reduce the carbon footprint of shea should retain these existing benefits. Three hypothetical low carbon alternative supply chains are tested here: 1) using stoves to reduce wood consumption by 25%; 2) using stoves to reduce wood consumption by 50% and; 3) mechanical extraction of shea butter. These scenarios were estimated to achieve around 19%, 37% and almost 20% emissions savings over traditionally produced shea respectively.