**5. Conclusion**

The present chapter presents a case study regarding the use of pollution indices for trace metals (TMs) contamination in sediments in Abobo-Doume Fish Market (ADFM) area in Côte d'Ivoire. According to the obtained data, the sediments collected along with the ADFM were particularly found contaminated in As, Cd, and Pb. The contamination index (CI), the mean contamination index (MCI), the contamination factor (CF), the pollution load index (PLI), the enrichment factor (EF), and the geoaccumulation index (Igeo) were applied for the assessment of the studied sediments. The CI values revealed a general contamination status of all of the sampling stations with TMs. In consideration with the MCI, the sampling stations were in the following contamination descending rank: S1 > S4 > S5 > S3 > S2. The CF suggests that the ADFM sediments were highly contaminated by As, Pb, Fe, and Cd, lowly contaminated by Hg. In consideration with the PLI values, sediments in the Abobo-Doume Fish Market were not polluted with TMs. The EF values have revealed an extremely high contamination for As, a very high enrichment for Pb, a deficiency to minimal enrichment for Cd, and a moderate enrichment for Hg. The Igeo values have highlighted that sediments in the ADFM area were extremely polluted for As, strongly and moderately polluted for Pb, and strongly to extremely polluted for Fe and Cd. The pollution indices used in the present study are useful tools for sediment contamination by TMs assessment in aquatic environments such as coastal areas. In conclusion, the CF was the most sensitive index as it revealed the contamination of the sediment by Hg despite its observed low concentrations and the PLI should not highlight the risk link to toxic TMs as As, Cd, Pb, Hg, etc. even at low concentrations in the environment.
