Ecotoxicological assessment of industrial wastewaters in Trancão River Basin (Portugal)

Abstract

It is important to assess the toxicity of complex effluents, since chemical evaluation alone is insufficient to protect the environment. Direct Toxicity Assessment is valuable in the decision process regarding the final disposal of complex wastewaters as it measures the total effects of the discharge, because of its known and unknown chemicals, additionally having some degree of ecological relevance. In Portugal, ecotoxicity tests are not used on a regular basis to control wastewaters. So, an integrated ecotoxicological, physical, and chemical study of wastewaters from 17 industries, in the Trancão River Basin, was carried out viewing proposing a test battery to be used in wastewater evaluation. An approach which does not include an ecotoxicological characterization may not properly evaluate the potential risks of effluent discharges, especially when they are complex. From the study carried out the use of a battery of assays to apply in the monitoring of complex wastewaters was proposed, including Microtox test, Daphnia test, and an algal test. Moreover, the added value of the ecotoxicological assessment of industrial wastewaters was demonstrated and could support the implementation of EU Directives (e.g. IPPC, WFD) within the Portuguese situation.

Multiple linear and principal component regressions for modelling ecotoxicity bioassay response

“…[1] The bacterium Vibrio fischeri (decomposer) and the alga Chlorella vulgaris (first producer) were selected for this study because they belong to diff erent trophic levels and are widely used in ecotoxicity tests. [1,2] One of the advantages of these tests is the fast assessment of ecotoxicity.…”

“…[1] The water quality assessment must comprise an ecotoxicological characterization, which allows properly evaluating the potential risks of effluent discharges, especially when they are complex. [2] The ecotoxicity evaluation by means of acute bioassays may bring quick and valuable information. [3,4] However, most of the ecotoxicity test methods were established to measure the toxicity of pure single chemicals and not to be applied to unknown environmental water samples with complex components.…”

Toxicological risk assessment of complex mixtures through the Wtox model

“…Each level corresponds to a particular risk classification. For each parameter, ranges of toxicological effect were established from outcome evaluations of researches already undertaken by LABTOX team members (Matias et al, 1998a;Matias et al, 1998b;Carvalho Pinto-Silva et al, 2003Perreault et al, 2011;Melegari et al, 2012;Flohr et al, 2012a;Flohr et al, 2012b),and studies in the available literature (Lambolez et al, 1994;Villegas-Navarro et al, 1999;Knops et al, 2001;Backhaus et al, 1997;Lappaleinen et al, 2001;Ç avas and Ergene-Gozucara, 2003;Rodriguez et al, 2006;Picado et al, 2008;Kang et al, 2010;Kostamo and Kukkonen, 2003;Grinevicius et al, 2009;Ç avas and Ergene-Gözükara, 2005;Avci et al, 2005;Huang et al, 2007).…”

The relationship between whole effluent toxicity (WET) and chemical-based effluent quality assessment in Vojvodina (Serbia)

“…There are many unsolved problems and opened questions, such as: (a) the relationship between the results of WET and chemical-based effluent quality assessment (Rodriguez et al 2006;Mendonca et al 2007;Picado et al 2008;Boillot et al 2008;Ra et al 2008); (b) the contribution of individual toxicants to overall toxicity of the effluent (Sarakinos et al 2000); (c) the interaction between potentially present toxicants and other compounds in the effluent, and consequently, the bioavailability of toxicants (Cedergreen et al 2008;Ra et al 2006b;Kramer et al 2004); (d) the problem of toxicity identification evaluation in complex mixtures (Brack 2003;Gutiérrez et al 2008;CaffaroFilho et al 2008;Eunhee et al 2008); and (e) the increasing need to find, establish and standardise alternative methods and end-points, including the application of genomic based tools in WET approach, which would be more sensitive to priority pollutants and emerging substances (Barata et al 2008;Kwon et al 2008).…”