Heavy Metal Pollution from Dental Clinics–Part 1:Annual Emissions Assessment

Document Type : Original Research Paper


1 Petrochemical and process engineering department, Laboratoire de Génie Chimique et Environnement de Skikda ,Postcode21000,Université20 Août 1955Skikda, Alegria

2 Laboratoire de Sécurité des Procédés Chimiques,Postcode76801, Normandie Univ, INSA Rouen Normandie, Rouen, France


This study aimed to evaluate the concentration of heavy metals in liquid effluents and to quantify the mercury content in dental amalgam waste generated by dental clinics. Three neighbouring cities in Northeast Algeria were considered in this study (Constantine, Skikda, and Annaba). Heavy metals, such as Hg, Cu, Zn, Fe, Ni, Mn, Cr, Cd, and Pb, were analysed in wastewater and then compared with acceptable standard values. Special attention was given to mercurybecause of its dangerous effects. The results collected indicated the presence of heavy metal contamination in dental wastewater. Heavy metal concentrations were significantly high for all heavy metals and exceeded the allowed concentrations. However, Pb and Cr were shown to have acceptable concentrations. This study highlights the possible contamination of the environment by mercury and heavy metals generated by dental clinics. This study also demonstrates an order of magnitude of the concentration of these heavy metal in a large agglomeration with a population of 2.5 million people.


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