Dental amalgam controversy emissions. The WHO also points out that amalgam separators, installed in the waste water lines of many dental offices, dramatically decrease the release of mercury into the public sewer system. In the United States, most dental practices are prohibited from disposing amalgam waste down the drain. Critics also point to cremation of dental fillings as an additional source of air pollution, contributing about 1% of total global emissions. It is the position of the FDI World Dental Federation as well as numerous dental associations and dental public health agencies worldwide that amalgam restorations are safe and effective. Numerous other organizations
Women in chemistry the only woman to be award two Nobel prizes). Her prize in chemistry was for her "discovery of the elements radium and polonium, by the isolation of radium and the study of the nature and compounds of this remarkable element." Irene Joliot-Curie, Marie's daughter, became the second woman to be awarded this prize in 1935 for her discovery of artificial radioactivity. Dorothy Hodgkin won the prize in 1964 for the development of protein crystallography. Among her significant discoveries are the structures of penicillin and vitamin B12. Forty five years later, Ada Yonath shared the prize with Venkatraman Ramakrishnan and Thomas