Akademik Veri Yönetim Sistemi
ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY, cilt.53, sa.3, ss.321-328, 2007 (SCI-Expanded)
The toxicity of leather tanning wastewater from a traditional tannery (TT), which is based on vegetable tannin (VT), was compared with wastewater from a tannery combining the use of chromium- based tanning (CT) with VT- based tanning operations. Wastewater samples from a TT and a CT plant as well as from five sewer sampling points were collected in Marrakesh, Morocco, and the concentrations of VT and some selected inorganics were measured. A set of bioassays were used to test wastewater toxicity in sea urchin (Paracentrotus lividus) embryos and sperm, in Daphnia magna, and in marine microalgae (Dunaliella tertiolecta). Toxicity end points included: (1) developmental defects, embryonic mortality, sperm fertilization success, and offspring damage in sea urchins; (2) D. magna immobilization; and (3) algal growth rate inhibition. Toxicity tests on TT and CT effluents (TTE and CTE) were run at dilutions ranging from 0.1% to 2% (sea urchins and algae) or up to 12% in D. magna. Parallel bioassays were run on VT extract (VTE) at nominal tannin concentrations ranging from 0.1 to 10 mg l - 1. The results showed higher toxicity of CTE compared with TTE. CTE toxicity in sea urchins and algae showed concentration- related trends, whereas TTE exerted hormetic effects at levels of 0.1% to 0.2% and toxic effects at levels 1%. The same trends were observed for VTE, suggesting a prevailing role of tannin in TTE-associated effects. The moderate wastewater toxicity of VT-based tanneries might prompt interest in the VT tanning process. An established body of evidence has associated the chromium-based leather tanning (CT) industry with environmental and occupational health concerns, which has been reviewed by several investigators (Losi et al. 1994; Battista et al. 1995; Chattopadhyay et al. 1999; Chandra et al. 2004; Meric, et al. 2005; Mwinyhija et al. 2006; Nath et al. 2005; Otero et al. 2005; Riva et al. 2005; Tagliari et al. 2004; Zhou et al. 2005). Unlike the CT industry, scanty information is available regarding the environmental impact of the traditional leather industry based on the use of vegetable tannin ( VT) and of a set of natural organic agents ( Anonymous 1974; De Nicola et al. 2004, 2006). Wastewater from VT- based tanneries is The toxicity of leather tanning wastewater from a traditional tannery (TT), which is based on vegetable tannin (VT), was compared with wastewater from a tannery combining the use of chromium-based tanning (CT) with VT-based tanning operations. Wastewater samples from a TT and a CT plant as well as from five sewer sampling points were collected in Marrakesh, Morocco, and the concentrations of VT and some selected inorganics were measured. A set of bioassays were used to test wastewater toxicity in sea urchin (Paracentrotus lividus) embryos and sperm, in Daphnia magna, and in marine microalgae (Dunaliella tertiolecta). Toxicity end points included: (1) developmental defects, embryonic mortality, sperm fertilization success, and offspring damage in sea urchins; (2) D. magna immobilization; and (3) algal growth rate inhibition. Toxicity tests on TT and CT effluents (TTE and CTE) were run at dilutions ranging from 0.1% to 2% (sea urchins and algae) or up to 12% in D. magna. Parallel bioassays were run on VT extract (VTE) at nominal tannin concentrations ranging from 0.1 to 10 mg l(-1). The results showed higher toxicity of CTE compared with TTE. CTE toxicity in sea urchins and algae showed concentration-related trends, whereas TTE exerted hormetic effects at levels of 0.1% to 0.