Energy audit and sustainability assessment of the production chain of Echium amoenum Fisch & Mey using a life cycle assessment

Echium amoenum Fisch & Mey, or borage, is a medicinal plant widely cultivated in northern Iran for its therapeutic value and traditional use. Despite its significance, no study has examined the energy efficiency and environmental sustainability of its production. This study provides a thorough evaluation of the energy audit and environmental impacts of borage herbal tea production using the Life Cycle Assessment (LCA) approach. As one of the first studies to apply this tool to a medicinal plant, this research addresses the gap in sustainability analysis for herbal product systems. Primary data were collected through structured questionnaires, field surveys, and direct interviews with farmers and processing facilities. The system boundary spans from cultivation to processing. Energy analysis revealed a total input energy of approximately 63261 MJ ha⁻¹ and an output energy of approximately 7727 MJ ha⁻¹ , resulting in low energy use efficiency (0.12) and high specific energy (about 121.7 MJ kg⁻¹). The Global Warming Potential (GWP) was estimated at 30.70 kg CO 2 eq per kg of product, with direct emissions from chemical fertilizers especially nitrogen accounting for 77.90 % of the total greenhouse gas (GHG) emissions. Endpoint damage assessment resulted in 4.82E-05 DALY for human health, 1.57E-07 species.year for ecosystems, and 0.60 USD for resources categories. Exergy analysis showed non-renewable fossil resources dominated demand at 79.40 MJ per kg of borage herbal tea, mainly from nylon packaging, while renewable water and biomass demands were lower at 28 MJ and 15.80 MJ, respectively. The study suggests the use of organic fertilizers, biofertilizers, and nitrogen-fixing crops, along with replacing nylon packaging with biodegradable materials, to reduce environmental impacts in the post-harvest and production chain of medicinal plants.