Abstract

Tanning industries have been vitally important to the economy of Bangladesh, yet they have been proven to be detrimental to the environment mainly due to the discharge of quantities of untreated wastewater containing chromium. Life cycle assessment (LCA) is a practical tool used to evaluate and compare the life cycle environmental impacts of a product. Using the IMPACT 2002+ methodology within the SimaPro LCA modelling tool, we have studied and compared the environmental burden of two leather products: full-chrome leather (FCL) and chrome-retanned crust leather (CRL). In the case of both FCL and CRL, it was found that significant environmental impacts were associated with tanning, rechroming, neutralisation, deliming-bating and the acid wash processes in the production cycle. The emissions responsible for these processes except deliming-bating, are Cr(III), Cr(VI) which plays a vital role in maximising the toxicity potential and ammonia (deliming-bating) to a minor extent. Supply chain hotspots are transport for raw hides, chemicals and electricity. FCL had 5 times, 4.53 times and 2.53 times greater impact on categories of aquatic ecotoxicity, non-carcinogens and ecosystem quality respectively compared to CRL. In addition, aquatic acidification potential of FCL was greater than that of CRL, while CRL had marginally higher contribution to aquatic eutrophication. The carbon footprint of the two systems was found to be about 0.75kg CO2 equivalent per m2 of leather. The assessment shows that the FCL production system has higher environmental impact than CRL.