Three doctors wrote the book The water we drink: the quality of water and its effects on health. Their names are Joshua I. Barzilay, MD, Winkler G. Weinberg, MD, and J. William Eley, MD. To put the issue of drinking water quality and its effects on health into perspective, the book is divided into three parts. It first examines the history of water, disease, and sanitation. The next section deals with health issues. At the conclusion of the book are chapters on bottled water and purification methods. The intent of the book is to educate consumers. In the ancient world there was an awareness of the need for sanitation and safe water for consumption. Efforts to keep water pure, maintain access to high-quality water, and provide wastewater disposal have been widely practiced. With the fall of the Roman Empire and the beginning of the Middle Ages these practices were largely forgotten and infectious diseases became common. Only with the rise of the scientific method and discoveries over the last hundred years has the connection between water quality, sanitation and health been rediscovered. The discovery that diseases were contagious and transmissible through water served as a reason for the development of water purification methods. In 1887, the first water filtration system was established in Lawrence, Massachusetts. Sand was the filter medium. In a short time the incidence of typhoid fever decreased enormously. In 1974, Congress passed the Safe Drinking Water Act. It established government control, through the Environmental Protection Agency (EPA), of surface and groundwater sources. “The EPA has established two types of regulations: (1) mandatory, enforceable maximum contaminant level (MCL) objectives, to be set as close as possible to the recommended health objectives, and (2) non-mandatory, community-based maximum contaminant level objectives. health (MCLG).” The chemicals and contaminants to be regulated were: microbiological contaminants, metals and inorganic chemicals, volatile organic chemicals, organic compounds and radionuclides. Despite the achievements, waterborne diseases remain a concern. “From 1971 to 1988, 564 infectious outbreaks occurred in the United States involving nearly 140,000 people.” Bacteria are microorganisms belonging to the kingdom of Prokaryotes. When certain bacteria appear in places where they don't normally reside, they can cause disease.