**5. Conclusion**

 From the study, it is evident that human influences like urbanization and agricultural activities are the major nutrient contributors to the marine environment through continuous discharge of untreated sewage effluents and agricultural runoffs delivered by rivers. Trace metal concentrations in estuaries, peri-urban creeks, and Lamu port were below the ER-L and ER-M indicating that there are no potential adverse effects on marine biota with an exception of Kilindini harbor that had a higher Cr concentration that may pose adverse effects. The concentrations of PAH, PCB, and OCP were generally high in Tana estuary as compared to the other estuaries in this study; however, the concentrations were lower than ER-L suggesting no potential impacts on organisms. It was also observed that the concentration level of ∑DDT was higher in Tana estuary than ER-L and lower for ER-M values suggesting that the accumulated persistent organic pollutants in sediments from Tana estuary could have a potential ecotoxicological impact on the benthic fauna. It is therefore important to put in place effective sewage and wastewater management strategies and implement good agricultural practices to manage the emerging pollution problem along the Kenyan Coast. A monitoring program for these pollutants is also important so as to always have an early warning.
