Life cycle assessment of Indian silk

The environmental impact of textiles is an area of increasing interest for consumers and legislators. Life cycle assessment (LCA) is the commonly used decision support tool for quantifying environmental impacts, and has been applied to most all major textiles. So far there has, however, been no cradle-to-gate assessment of raw silk production. On the basis of a review of literature on silk production, this paper constructs a first life cycle inventory of the production of high-quality silk under tropical conditions in southern India. Values are calculated for the following environmental impact indicators: global warming potential, ecotoxicity, freshwater eutrophication, land occupation, cumulative energy demand and blue water footprint. The functional unit is defined as 1 kg raw silk, at factory gate. The analysis compares best practice recommendations with observed farm practices. Where applicable, data gaps have been highlighted. Results indicate that silk production following recommended practices is input intensive and that on a mass basis, environmental impacts are above those reported for other natural fibres. The majority of environmental impacts stem from cocoon production, in particular fertilization. Farm practices diverge from recommendations significantly and the observed impact per functional unit is higher. The multiple stages required to manufacture raw silk result in a large amount of co-products. Increasing the efficiency in utilisation of these could reduce the high impact observed in this study.