Amalgam (dentistry) shown any adverse effects for the mother or fetus. However, research is inadequate to determine the chance of harm occurring and therefore placement and removal should be avoided during pregnancy if possible. In response to The Minamata Convention on Mercury, the European Commission has confirmed its position that individual nations should work to gradually scale down the use of dental amalgam. Dental amalgam is thought to be relatively safe to be used as a restorative material as it is used in low doses. Amalgam vapour can be released through chewing but this is minimal. However, there is an increased release
Chemical element whole number. For example, the relative atomic mass of chlorine is 35.453 u, which differs greatly from a whole number as it is an average of about 76% chlorine-35 and 24% chlorine-37. Whenever a relative atomic mass value differs by more than 1% from a whole number, it is due to this averaging effect, as significant amounts of more than one isotope are naturally present in a sample of that element. Chemists and nuclear scientists have different definitions of a "pure element". In chemistry, a pure element means a substance whose atoms all (or in practice almost all) have the