**4. Conclusion**

The aim of this study is: (i) to analyze the contribution of geological factors and anthropogenic actions in the alteration of water quality in Port-au-Prince. The toxicology of chemicals of three heavy metal (chromium, lead, and nickel) and fluoride, substances detected in groundwater and tap water, has been reviewed. The information available on the effects of the selected heavy metals highlights major chemical risks, particularly for children, relating to Pb (II), Cr (III), Cr (VI) and Ni (II) contained in the groundwater were also characterized [27]. The level of pollution of underground water resources in the metropolitan area of Port-au-Prince does not only require the application of an approach based on water treatment processes. It also reflects the need to approach the issue of the quality of water intended for human consumption in this urban space based on a transdisciplinary approach based on the theories of medical geology and the approach. One Health. Indeed, the level of organic and mineral pollution of these resources can compromise the rare efforts made to achieve the SDGs, more particularly the 3, 6, 11, 13. The results available in the literature and used in the context of this work clearly indicate the existence of chronic toxicities of trace heavy metals (Cr, Pb, Ni), fluoride and hardness of drinking water on the human organism and on kidney tissues. In the future, it will be necessary to initiate research work on the combined effects of these substances from observations on laboratory animals and then proceed to modeling to finally arrive at an understanding of certain interactions that may exist between these pollutants.

#### **Acknowledgements**

The authors are thankful to the "One Health" University Space of Quisqueya University, FOKAL-Open Society Foundation Haiti, the Agence universitaire de la Francophonie (AUF), the Representation of the Institute for Research for Development (IRD) in Mexico, Cuba, and Haiti, the SCAC (Service for Cooperation and Cultural Action) of the French Embassy in Haiti, and the AOG (Association communautaire paysanne des Originaires de Grande Plaine) for their support in carrying out this work.

*Environmental Health*
