Multi-criteria Assessment of Heavy Metals contaminations in waters and ranking the sites by using PROMETHEE/GAIA method

PurposeIn this study, Multi-criteria decision making (MCDM) approach was applied to assess and evaluate the heavy metals (Cr, Mn, Co, Ni, Cu, Zn, As, Cd, Pb and Hg) pollution in Dilovas region (one of the largest industrial area in Turkey).MethodsThe heavy metal content of 10 different locations have been evaluated and these locations are ranked according to their metal contents by using PROMETHEEGAIA method, which is one of the pairwise comparisons MCDM methods. PROMETHEE (Preference Ranking Organization Method for Enrichment Evaluation) method was used to rank the locations according to their heavy metal content and GAIA (Geometrical Analysis for Interactive Aid) method was used to analyse and show the relations between alternatives (locations) and criteria (heavy metal).ResultsAnalysis indicated that location d4 (small harbor of Hereke) is the most polluted especially by Pb, Cd, Cr and As. The location d8 is the least polluted area which is the farthest places from the harbors and industrialized zones.ConclusionsThe ranking results clearly showed that the most contaminated locations are wastewater discharge points and small ports. The study also showed that PROMETHEE/GAIA method is very helpful to analyse environmental problems.