Dental amalgam controversy (unlike composites), and is often about 20-30% less expensive. "Consumer Reports" has suggested that many who claim dental amalgam is not safe are "prospecting for disease" and using pseudoscience to scare patients into more lucrative treatment options. Those opposed to amalgam use suggest that modern composites are improving in strength. In addition to their claims of possible health and ethical issues, opponents of dental amalgam fillings claim amalgam fillings contribute to mercury contamination of the environment. The World Health Organization (WHO) reports that health care facilities, including dental offices, account for as much as 5% of total waste water mercury
Actinide chemistry Actinide chemistry Actinide chemistry (or actinoid chemistry) is one of the main branches of nuclear chemistry that investigates the processes and molecular systems of the actinides. The actinides derive their name from the group 3 element actinium. The informal chemical symbol An is used in general discussions of actinide chemistry to refer to any actinide. All but one of the actinides are f-block elements, corresponding to the filling of the 5f electron shell; lawrencium, a d-block element, is also generally considered an actinide. In comparison with the lanthanides, also mostly f-block elements, the actinides show much more variable valence. The