Toxicity Test of Chromium and Glutaraldehyde to Determine Greener Chemical in Tannery Industry Laili Rachmawati a * and Mustafidah Udkhiyati b Leather Tanning Technology Department of Polytechnic ATK Yogyakarta, Indonesia a lailirachma@gmail.com, b ukyfida@gmail.com Keywords: Tanning Material, Chromium, Glutaraldehyde, Toxicity, Greener Chemical Abstract. The aim of this study was to investigate the toxicity level of chromium and glutaraldehyde. This research was conducted by testing the resistance level of fungi (Aspergillus niger sp.) toward glutaraldehyde and chromium in the medium of Potato Dextrose Agar (PDA). Variable of this experiment was the growth of Aspergillus niger sp. that indicates the resistance level of Aspergillus niger sp. The growth rate of Aspergillus niger sp. was classified on four scales. They were, (I) scale 1: zero growth; (II) scale 2: low growth (+); (III) scale 3: medium growth (++); (IV) Scale: 4 high growth (+++). All collected data were analysed by One Way ANOVA. The result showed that the toxicity of chromium and glutaraldehyde tanning material were highly significantly different toward Aspergillus niger (P<0,01). The Aspergillus niger sp. growth rate scale in chromium medium was high (scale 4: 4.00±0.00). Meanwhile, the growth rate scale of the Aspergillus niger sp. in glutaraldehyde medium was low (scale 2: 1.33 ± 0.58). Based on the fungi growth rate, it can be concluded that glutaraldehyde was more toxic than chromium tanning material toward Aspergillus niger sp. Furthermore, it can be said that glutaraldehyde is not quite ideal to be used as an alternative of chromium as a tanning material. Introduction Most of the tanning material that commonly used in tannery industry is chromium compound [Cr(OH)SO 4 ]. Leather tanned using chromium has advantages that until today are difficult replaced by other tanning materials. Chromium provides highly flexible, enervate, and supple leather characteristics. And the most prominent, leather chromium has a highly hydrothermal resistance, which could reach 140 °C [1]. This tanning material can be applied to all kinds of leather articles, especially for leather types that require a high degree of protective personal equipment, such as gloves, garment, and upholstery leather. Besides the advantages that possessed by chromium, this compound in certain form and concentrations are toxic to humans, animals, and plant. It is according to the oxidation number of chromium compounds, each type has a different role in the environment and the different effects to human health or growth of plants. Chromium with oxidation number of 6 (Cr 6+ ) is the most dangerous chromium compound (e.g. K 2 CrO 4 and CrO 3 ). Thus, it can be categorised as a toxic and hazardous material [2]. Nowadays, one of alternatives tanning material that developed as a replacement for chromium is aldehyde compound. Aldehyde compound consists of two common types; they are formalin (formaldehyde) and glutaraldehyde. But according to Industrial Statue at the year 2007, formalin included in the toxic and hazardous materials because of its toxic, mutant, as well as carcinogenic so in its use and management must obtain a special permit. This causes, the use of formalin in the field becomes rare. Meanwhile, the other type of aldehyde compound which is glutaraldehyde, still commonly used as a pre-tanning agent of shrunken leather and re-tanning agent of glove leather. Glutaraldehyde began much developed because it is known to have close results of enervation to leather chromium [3]. Besides being used as a tanning material, glutaraldehyde is commonly used in large quantities by a variety of industries, some of them as a disinfectant agent, preservative, fixation agents, and as Materials Science Forum Submitted: 2016-11-24 ISSN: 1662-9752, Vol. 901, pp 160-165 Revised: 2017-01-09 doi:10.4028/www.scientific.net/MSF.901.160 Accepted: 2017-03-16 © 2017 Trans Tech Publications, Switzerland Online: 2017-07-14 All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of Trans Tech Publications, www.ttp.net. (#89500574-19/05/17,08:54:16)