Research Article Use of Mercury in Dental Silver Amalgam: An Occupational and Environmental Assessment Nadia Jamil, 1 Mujtaba Baqar, 1 Samar Ilyas, 1 Abdul Qadir, 1 Muhammad Arslan, 2 Muhammad Salman, 3 Naveed Ahsan, 4 and Hina Zahid 1 1 College of Earth and Environmental Sciences, University of the Punjab, Lahore 54590, Pakistan 2 College of Petroleum and Geosciences, King Fahd University of Petroleum & Minerals, Dhahran 31261, Saudi Arabia 3 Institute of Chemistry, University of the Punjab, Lahore 54590, Pakistan 4 Institute of Geology, University of the Punjab, Lahore 54590, Pakistan Correspondence should be addressed to Mujtaba Baqar; mujtababaqir@gmail.com Received 9 February 2016; Accepted 8 June 2016 Academic Editor: Blanca Lafon Copyright © 2016 Nadia Jamil et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Te objective of this study was to assess the occupational exposure to mercury in dentistry and associated environmental emission in wastewater of Lahore, Pakistan. A total of ninety-eight blood samples were collected comprising 37 dentists, 31 dental assistants, and 30 controls. Results demonstrate that the dentistry personnel contained signifcantly higher mean concentration of mercury in their blood samples (dentists: 29.835 g/L and dental assistants: 22.798 g/L) compared to that of the controls (3.2769 g/L). Te mean concentration of mercury was found maximum in the blood samples of older age group (62.8 g/L) in dentists and (44.3 g/L) in dental assistants. Te comparison of mercury concentration among dentists, dental assistants, and controls (pairing based on their ages) revealed that the concentration increased with the age and experience among the dentists and dental assistants. Moreover, the mercury concentration in all the studied dental wastewater samples, collected from twenty-two dental clinics, was found to be exceeding the recommended discharge limit of 0.01 mg/L. Terefore, we recommend that immediate steps must be taken to ensure appropriate preventive measures to avoid mercury vapors in order to prevent potential health hazards to dentistry personnel. Strong regulatory and administrative measures are needed to deal with mercury pollution on emergency basis. 1. Introduction Mercury has been used in dental silver amalgam for the last two centuries [1], as a dental restorative flling material. Tis material contains mercury in about 50% of its total mass and the remaining constituents are silver, tin, copper, zinc, and other trace metals [2]. Tough the dental amalgam is widely used, however, its injudicious handling consequently leads to human health risk, particularly associated with occupational exposure and environmental damage from mercury emission [3]. Some alternative flling materials are also available in dentistry but low cost, durability, and easiness in handling and placement have maintained the popularity of the mer- cury based dental amalgam in most parts of the world, where it is used as flling material in posterior teeth [4, 5]. Te development of Minamata and Convention on Mercury, an international treaty adopted by 139 countries, came forward as a major instrument to call a voluntary phase-down of mercury use in dental amalgam [6, 7]. Te dentist and their assistants have been occupationally exposed to diferent forms of mercury across the world [8, 9]. More specifcally, elemental mercury vapors (HgO) are con- sidered as a major form due to manipulation of dental amal- gam in their several routine occupational tasks, including preparation, restoration, and removal of dental amalgam [10]. Approximately, 80% of the inhaled mercury vapors is captivated in the blood stream, circulates throughout the body, and can pass through both the placental and the blood- brain barriers [4, 11]. Furthermore, dental personnel are also exposed to inorganic mercury (mercuric salts, mercurous compounds) and organomercurials from contaminated diet intake and mercury stemming from their own dental amal- gam fllings [11]. Hindawi Publishing Corporation BioMed Research International Volume 2016, Article ID 6126385, 9 pages http://dx.doi.org/10.1155/2016/6126385