If the pipes leading to a home are old and have corroded, lead can leach into the water supply of a home. Lead can accumulate and it is advised that the water run for awhile before consuming it and to only use cold water which would have less lead in it. Lead can result in physical and mental developmental delays in children and in adults can increase blood pressure and lead to kidney problems. Homes built prior to 1986 are at most risk for lead pipes. Most municipal water supplies in the United States are excellent at monitoring and eliminating disease pathogens from water. However, interruption or intermittant treatment can cause waterborne outbreaks. All public water systems in the U.S. must follow standards and regulations set by the Environmental Protection Agency(EPA). Fluoridation of water has helped the public fight tooth decay in the last century and clean water technologies is touted to have a rate of return of 23 to 1 for investments in water filtration and chlorination for the public health.