Investigation into the Hazards of Finished Cr-tanned Leather as both Product and Waste

摘要

In this study, the hazardous substances in finished chrome-tanned leather and in leachates were determined and evaluated based on ISO or national standards, and the overall toxicity toward Photobacterium phosphoreum of the leachates was assessed. No restricted hazardous substances, such as Cr(VI), HCHO and carcinogenic dyes in leathers exceeded the thresholds proposed in the criteria for eco-label leather products. Chrome leathers were then leached with deionized water with a solid/liquid ratio of 1:20 to simulate rainwater leaching, and the heavy metals as well as organic compounds in leachates were analysed by ICP-OES, spectrophotometry, and GC-MS. The total chrome, Cr(VI) and TOC in the leachates of leathers were about 2.6-2.8, 0 and 237-277mg/L, repectively, and the low contents of hazardous substances in leachates showed that leather should not be considered as toxic waste when discarded. However, the biotoxicity assays of the leachates from leathers showed quite a high luminescence inhibition rate of about 97-98%, suggesting a hazard to aquatic organisms. Though the leachable chrome showed the greatest concentration in general, the toxicity of leachates seems complicated and further studies are needed.