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Six-Year Review 1 of Drinking Water Standards

In July 2003, EPA announced the review results for the first Six-Year Review (called the Six-Year Review 1). EPA reviewed 69 national primary drinking water regulations (NPDWRs) that were established prior to 1997. These 69 NPDWRs include 68 chemical NPDWRs and the Total Coliform Rule (TCR). Based on the Agency's review, as well as the public comments received and other new information, EPA found that it was appropriate to revise the Total Coliform Rule (TCR). EPA found that it was not appropriate to revise the 68 chemical NPDWRs at that time.

On this page:

 

Summary of Six-Year Review 1 Results

Learn more about the drinking water contaminants listed below

Summary of Review Outcomes

Regulated Contaminants

Not Appropriate for Revision at this Time

Risk assessment in process1:
chemical currently undergoing an EPA health risk assessment;
includes the three initiated as a result of this review
(34 NPDWRs)
Acrylamide
Alachlor
Antimony
Asbestos
Atrazine
Benzo[a]pyrene
Cadmium                  
Carbofuran
Carbon tetrachloride
Copper             
Cyanide             
2,4-D (2,4-Dichlorophenoxyacetic acid)
1,2-Dichlorobenzene
1,4-Dichlorobenzene
1,2-Dichloroethane
Di(2-ethylhexyl)adipate
Di(2-ethylhexyl)phthalate
Diquat
Endothall
Ethylbenzene
Ethylene dibromide
Glyphosate
Methoxychlor
Pentachlorophenol
Polychlorinated biphenyls
Simazine
Styrene
2,3,7,8-TCDD (Dioxin)
Tetrachloroethylene
Toluene
1,1,1-Trichloroethane
Trichloroethylene
Xylenes

NPDWR remains appropriate after data/information review(16 NPDWRs)

Barium
Dalapon
cis-1,2-Dichloroethylene
trans-1,2-Dichloroethylene
Dinoseb
Endrin
Epichlorohydrin
Hexachlorocyclopentadiene
Mercury
Monochlorobenzene
Nitrate
Nitrite
Selenium
2,4,5-TP (Silvex)
1,2,4-Trichlorobenzene
Vinyl chloride

New information, but no revision recommended because:

Low priority
(14 NPDWRs)

Benzene
Beryllium
Chlordane
1,2-Dibromo-3-chloropropane
1,1-Dichloroethylene
1,2-Dichloropropane
Heptachlor
Heptachlor epoxide
Hexachlorobenzene
Lindane
Oxamyl
Picloram
Toxaphene
1,1,2-Trichloroethane

Information gaps
(4 NPDWRs)

Chromium
Dichloromethane
Fluoride
Lead

Candidate for Revision

Based on review of "other regulatory provisions" (1 NPDWR)

Total Coliform Rule (TCR)

1. As of December 31, 2002, EPA was conducting or had scheduled a detailed review of health effects information.


Federal Register Notices and Fact Sheet


Support Documents for EPA’s First Review of Existing Drinking Water Standards