Journal of Hazardous Materials A85 (2001) 181–191 Case study Environmental assessment of lubricants before and after wire drawing process M.C. Ruiz ∗ , J. Verde, A. Andrés, J. Viguri, A. Irabien Dpto. Ingenier´ ıa Qu´ ımica y Qu´ ımica Inorgánica, ETSII yT, Universidad de Cantabria, Avda. de los Castros s/n, 39005 Santander, Cantanbria, Spain Received 14 September 2000; received in revised form 26 March 2001; accepted 2 April 2001 Abstract Iron wire drawing processes involve the use of solid lubricants made of powdered raw materials, which lead to industrial wastes after being used. These wastes, based on stearates, have a negative effect on the environment. This study deals with the environmental assessment of some lubricants before and after the wire drawing process in a Spanish factory. The parameters evaluated for this study have been total organic carbon (TOC), mobility of zinc and lead, and ecotoxicity (EC 50 ). Results show that wastes have more ecotoxicity than the original lubricants due to the content of metals that lubricants pick up from the wire, as pickling, patenting and galvanising take part in the manufacture. The capture of metallic particles leads to a reduction of TOC and an increase in ecotoxicity. © 2001 Elsevier Science B.V. All rights reserved. Keywords: Wire drawing; Solid lubricants; Wastes; Ecotoxicity 1. Introduction Wire drawing processes are well established [1]. The efficiency of a drawing technique mainly depends on the lubricating methods. The lubricants selection is done taking into ac- count quality criteria, wire mill activity and operational efficiency, which includes the costs of operation. Moreover, these costs of operation could be higher if environmental criteria were not taken into account to choose the appropriate lubricant. The chemical pretreatment of working material, pickling and phosphating, pollute rinsing waters with chloride and phosphoric acid, metal ions, phosphate, chlorate, nitrate and nitrite; consequently, waste water treatment is necessary. Research and development activities are focused now on the ∗ Corresponding author. Tel.: +34-942-201590; fax: +34-942-201591. E-mail address: ruizpm@unican.es (M.C. Ruiz). 0304-3894/01/$ – see front matter © 2001 Elsevier Science B.V. All rights reserved. PII:S0304-3894(01)00227-8