Dental amalgam controversy of discarded mercury and dental amalgam a mere 0.56 percent". Mercury is an environmental contaminant and the WHO, OSHA, and NIOSH have established specific occupational exposure limits. Mercury imposes health risks upon the surrounding population. In economics, this pollution is considered an external cost not factored into the private costs of using mercury-based products. Environmental risks from amalgam can be mitigated by amalgam separators and the ISO has issued standards regarding the proper handling and disposal of amalgam waste. It should be noted, however, that mercury is a naturally occurring element that is present throughout the environment and the vast
Alchemy and chemistry in medieval Islam that have come down through the years were preserved as Arabic translations. In considering Islamic sciences as a distinct, local practice, it is important to define words such as "Arabic," "Islamic," "alchemy," and "chemistry." In order to gain a better grasp on the concepts discussed in this article, it is important to come to an understanding of what these terms mean historically. This may also help to clear up any misconceptions regarding the possible differences between alchemy and early chemistry in the context of medieval times. As A.I. Sabra writes in his article entitled, "Situating Arabic Science: Location versus Essence,"