The environmental concern about mercury is that it does not degrade, but it can change from one form to another and will migrate through the environment. Under certain conditions in surface waters, microorganisms can convert some forms of mercury to methyl mercury, which is highly toxic. Fish and other aquatic organisms can absorb methyl mercury, and because fish cannot eliminate methyl mercury from their tissue, methyl mercury can bio accumulates up the food chain. Regular consumption of fish with methyl mercury in high enough concentrations can cause harm to both wildlife and humans. Dental amalgam has been the subject of attention by environmental regulators because it contains elemental mercury as a major component. Therefore, recommend that immediate steps must be taken to ensure appropriate preventive measures to avoid mercury vapours 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. This paper discuss about the environmental health hazardous for dentist like mercury, lead, silver and other biomedical waste in dental clinic.