A total of 120 households in eight communities across California provided water samples as part of one of the most comprehensive studies of unmonitored potential carcinogens in diverse drinking water sources. The study provides the information to assess statewide exposure to potential carcinogens and endocrine disrupting compounds. The study employed an innovative and integrated application of four distinct organic compound detection technologies that have recently been validated for environmental monitoring applications but had never before been jointly applied to drinking water.