Public Health and Environmental Health Practice Exam

Maximum Contaminant Level is the highest allowable concentration of a contaminant in drinking water under regulatory standards. It’s enforceable and set to protect public health, taking into account how toxic a contaminant is and what level of treatment and cost are feasible. Regulators, such as the EPA, use MCLs to require water systems to monitor and keep contaminant levels below that limit, with enforcement actions if a level is exceeded. They’re expressed in concentration units like milligrams per liter or micrograms per liter, and there’s also a non-enforceable health-based goal called the Maximum Contaminant Level Goal that represents a lower, ideal target.