The results of a 'BioWise' demonstration project to assess the comparative sensitivity and practicality of seven new assays for the direct assessment of ecotoxicity in industrial effluents are presented. In addition the aim of the project was to validate the results of the new assays against benchmark data generated from non-proprietary, rapid, microplate screening assays using the regulatory species; freshwater crustacean Daphnia magna and green algae Selenastrum capricornutum, chosen in view of their environmental relevance. The new commercial test assays were: Daphnia magna, Selenastrum capricornutum and Thamnocephalus platyurus Toxkits supplied by Vickers Laboratories Ltd, containing dormant, immobilised life stages of the test species; GreenScreen EM, a yeast based assay for genotoxicity and general acute toxicity supplied by Gentronix Ltd; and CellSense a mediated, amperometric whole cell biosensor based on immobilised activated sludge and E. coli. 38 effluent samples supplied by members of SOCSA (Specialised Organic Chemicals Sector Association) were examined over a period of 13 months, in the project co-ordinated by the AstraZeneca Brixham Environmental Laboratory, and part funded by BioWise via the UK Government Department of Trade and Industry.
This study was conducted with undergraduate students to evaluate the impact of chemical sludge recirculation on the overall removal efficiency and reduction of virgin chemicals. This project was also performed to demonstrate to students and faculty of the Civil Engineering Technology (CET) program at Southern Polytechnic State University (SPSU) the capabilities of the environmental laboratory, while encouraging the students to participate in applied research.Studies conducted by Kolthoff and Overholser (1)(2) , and subsequent work by Davies, Leckie, Benjamin and others (3)(4)(5)(6)(7) have demonstrated the effectiveness of co-precipitation and the adsorptive capacity of hydrous oxides. Our intent was to increase the precipitate in contact with synthetic rinse water, and determine its impact on the overall efficiency of the precipitation process in two different scenarios. The first scenario evaluated consisted of a synthetic rinse water containing copper only. The second scenario consisted of rinse water containing different copper to iron ratios. MaterialsThe precipitation experiments were conducted on synthetic rinse water containing approximately 50 mg/L Cu. Copper sulfate (CuSO 4 . 5H 2 O, Fisher Scientific, Co.) was used as the copper source. The ionic background for the synthetic wastewater was maintained at approximately 10 -2 M with sodium chloride. The pH of the rinse water was adjusted to 2.0 using HNO 3 (Fisher Scientific Co.). A Fe (III) stock solution prepared from FeCl 3 crystals (Fisher Scientific Co.) was used as a source of iron for the second set of experiments. Sodium hydroxide and calcium hydroxide solutions were used to adjust the pH, and to compare their effectiveness in the precipitation process.Residual concentrations of copper were determined colorimetrically by reaction with bicinchoninic acid (Hach Methods) (8) . This colorimetric method has an optimum operational range of 0.01 -5.0 mg/L. All pH values were determined using an Accumet Basic pH meter Model AB15 (Fisher Scientific Co.), calibrated with certified Fisher Scientific buffer solutions at pH 4.0 and 7.0. Total suspended solids analyses were conducted according to the Standard Methods (9) on the recycled sludge.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.