Mercury is a large component of dental fillings, but it is not believed to pose immediate health risks in that form. When exposed to sulfate-reducing bacteria, however, mercury undergoes a chemical change and becomes methylated, making it a potent, ingestible

Hormonal contraception may become a safe, effective, and reversible form of birth control for men, according to a new study. The study revealed that the combination of testosterone and progestin suppressed sperm production faster and more completely than testosterone alone.