Mercury (Hg) has long been known to be detrimental to human health. Despite this knowledge, many ancient medicines contained mercury, and as recently as the last century mercurochrome was used as a common household skin disinfectant. There are natural environmental mercury sources (e.g., active volcanoes), but in industrial times most exposures to mercury resulted from human activities such as coal-burning, some gold-mining techniques, the hat-making industry, and gilding. We will look at the global history of mercury pollution, with the 1950s Minamata catastrophe in Japan representing a sad landmark case, and illustrate current mercury pollution, including some sources in CT. The use of lead (Pb) in leaded gasoline and paint has resulted in extensive Pb exposure of humans, which can result in brain damage, and some sociologists have correlated Pb exposure in children to increased crime rates later in life. Lead in water supply lines is an ongoing concern (remember Flint, Michigan). This course will look at the main natural and anthropogenic sources of these pollutants, the way humans take them up, the health effects, and policies that have been designed to protect the public.