MAXIMUM CONTAMINANT LEVELS FOR TOXIC SUBSTANCES IN WATER: A STATISTICAL APPROACH1

ABSTRACT: A method to establish maximum contaminant levels or nondegradation standards for toxic substances in water is described. The method described is based on statistical outlier procedures which distinguish ubiquitous background levels of toxic substances from those concentrations significantly greater than background. Because this approach utilizes environmental data, it can calculate an interim maximum contaminant level which can help protect the public until sufficient health effects data are available to establish human health based maximum contaminant levels.