People with more than eight dental fillings may have 150% more mercury in their blood, increasing the risk of brain, heart and kidney damage, a new study has found. Dental surface restorations or,known as dental fillings, is composed of an amalgamation of mercury, silver, tin and other metals. The research by a team from University of Georgia analysed data from 15,000 individuals and is the first to demonstrate a relationship between dental fillings and mercury exposure. “Tooth decay is one of the most prevalent chronic diseases. But the kind of materials the dentist uses is not something that is really discussed,” said Lei Yin, a scientist at University of Georgia. Researchers further analysed exposure by specific types of mercury and found a significant increase in methyl mercury, which is the most toxic form, related to dental fillings. Xiaozhong Yu, an assistant professor, said this result suggests the human gut microbs, microorganisms living in the intestines, may transform different types of mercury. People with dental fillings who are also exposed to mercury from other sources, such as seafood, are most at risk. The study also looked at dental composite resins, a mercury- free alternative for fillings that can release bisphenol A which may cause reproductive damage.