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The assessment of the actual impact of discharged wastewater on the whole ecosystem and, in turn, on human health requires the execution of bioassays. In effect, based on the chemical characterization alone, the synergistic/antagonistic effect of mixtures of pollutants is hardly estimable. The aim of this work was to evaluate the applicability of a battery of bioassays and to suggest a smart procedure for results representation. Two real wastewater treatment plants were submitted to analytical campaigns. Several baseline toxicity assays were conducted, together with tests for the determination of endocrine activity, genetic toxicity and carcinogenicity of wastewater. A "traffic light" model was adopted for an easy-to-understand visualization of the results. Although the legal prescriptions of chemical parameters are fully complied with, bioassays show that a certain biological activity still residues in the treated effluents. Moreover, influent and effluent responses are not always appreciably different. Some tests employing human cells were revealed to be only partially adequate for environmental applications. An interesting and helpful development of the present approach would consist in the estimation of biological equivalents of toxicity, as shown for the estrogenic compound 17-β-estradiol.

Several indicators for the evaluation of the MSW collection systems have been proposed in the literature. These evaluation tools consider only some of the aspects that influence the operational efficiency of the collection service. The aim of this paper is to suggest a set of (easy to calculate) indicators that overcomes this limitation, taking into account both the characteristics of collected waste and the operational - economic performance. The main components of the collection system (labour, vehicles and containers) are separately considered so that it is possible to quantify and compare their role within the whole process. As an example of application, the proposed approach was used for comparing the MSW collection strategies adopted in four towns in Northern Italy. Results are discussed and a comparison with alternative assessment methods available in the scientific literature is reported., (Copyright © 2018 Elsevier Ltd. All rights reserved.)