National Drinking Water

EPA must first make determinations about which contaminants to regulate. These determinations are based on health risks and the likelihood that the contaminant occurs in public water systems at levels of concern. The National Drinking Water Contaminant Candidate List (CCL), published March 2, 1998, lists contaminants that (1) are not already regulated under SDWA (2) may have adverse health effects (3) are known or anticipated to occur in public water systems and (4) may require regulations under SDWA. Contaminants on the CCL are divided into priorities for regulation, health research and occurrence data collection. 

NDWAC National Drinking Water Advisory Council... 

Consultation-June 6-9, 2000 National Drinking Water Survey Design for Assessing Chronic Exposure. USEPA, Washington, DC (2000). Also available on the World Wide Web http //www.epa.gOv/scipoly/sap/2000/ index.htm, accessed August 2002. 

As regulated by EPA (as of January 1, 2002), the maximum residual disinfectant level (MRDL) for chlorine dioxide is 0.8 mg/L (EPA 2002g) the maximum contaminant level (MCE) for its oxidation product, chlorite ion, in drinking water is 1.0 mg/L (EPA 2002e). The levels of chlorite ion in distribution system waters have been reported as part of the Information Collection Rule (ICR), a research project used to support the development of national drinking water standards in the United States (EPA 2002d). 

TABLE 1 WHO Guideline Values for Chemicals in Drinking Water and EPA National Drinking Water Standards [2,3] ... 

Republic of China Environmental Protection Administration (1998) National Drinking Water Quality Standards, Environmental Protection Administration, Taiwan, Republic of China. 

Z.M. Lahlou, Point of use/point of entry systems, A National Drinking Water Clear-ingHouse Fact Sheet, Available at http //www.nesc.wvu.edu/ndwc/pdf/OT/TB/ TB Sp03 point.pdf (Accessed October 2005). 

National Drinking Water Clearinghouse, Organic Removal, Tech Brief, Aug, 1997. 

V. Bhardwaj and M. J. Mirliss, Diatomaceous Earth Filtration for Drinking Water, National Drinking Water Clearinghouse, West Virginia University, Morgantown, WV, 2001. 

EPA. 2000c. National drinking water contaminant occurrence query user s guide. National contaminant occurrence database. U.S. Environmental Protection Agency. 

EPA has not yet developed a national drinking water standard for DBCP (8), The 1978 DHS drinking water action level of 1.0 ppb was adopted before current information on carcinogenicity was available. EPA has since estimated a lifetime cancer risk from consuming 2 liters per day of water containing 1 part per billion DBCP as 180 excess cancer incidents per million population exposed (9). Figure 7 depicts the EPA estimated cancer risk at various DBCP water concentrations. The State of Hawaii in 1984 adopted a water quality limit of 0.02 ppb (20 ppt)(10). In view of DBCP s potential cancer impacts at very low concentrations, SWRCB has recommended that DHS lower the California DBCP action level to the current detection limit of 0.02 parts per billion (11). 

Cowie C., Pilotto L., Douglas R., BursiU D., W ade A., Reynolds C., Rouch G., Ho W., Chapman M., Bree D., Jones R. (1996), A national drinking water quality database, Proc. of WaterTECH, AWWA, Sydney, Mav 96,433-438. 

Overall there appears to be considerable uniformity in the concentration of di- -butyl phthalate in the surface waters of the United States, if locally contaminated areas are excluded. The National Drinking Water Contaminant Occurrence Database (NDOD), which contains data from ambient water samples, lists... 

GNDWM. Prevention and Control of Fluorosis in India Water Quality and Defluoridation Techniques, vol. 2, Rajiv Gandhi National Drinking Water Mission, Ministry of Rural Development, New Delhi, 1993. 

SDWA has provisions that provide for the collection, organization and sharing of occurrence data on contaminants of potential concern. The National Drinking Water... 

In developing national drinking-water standards based on the these guide-... 

Douglas, L, Guthmann, J., Muylwyk, Q. and Snoeyink, V. (2004). Corrosion control in the City of Ottawa-Comparison of alternatives and case study for lead reduction in drinking water. In W. Robertson and T. Brooks (eds.), 11th Canadian National Drinking Water Conference and 2nd Policy Forum, April 3-6, Calgary, AB. Canadian Water and Wastewater Association, Ottawa, ON. 

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