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National Drinking Water Database

National Drinking Water Database - Chemical Contaminants

Hydrogen sulfide

Status: Unregulated - EPA has not established a maximum legal limit in tapwater for this contaminant.

Hydrogen sulfide is a constituent of crude petroleum and natural gas; it is also released from decomposing waste in landfills and sewers and from food processing factories, coke ovens, paper mills, tanneries, and petroleum refineries.

Found above
health guidelines
Found above
legal limit
Water utilities
People Served

Hydrogen sulfide Exposure by State

Water utilities in 3 states have reported detecting Hydrogen sulfide in treated tap water since 2004, according to EWG's analysis of water quality data supplied by state water agencies.

StateWater Suppliers with Hydrogen sulfide contamination
New Hampshire241175,844
New York148

The Most Polluted Communities

244 water utilities reported detecting Hydrogen sulfide in tap water since 2004, according to EWG's analysis of water quality data supplied by state water agencies

Ranked by highest average Hydrogen sulfide level

RankSystem Population Served Positive test results of total reported tests Average Level
1Dublin Consolidated School
1501 of 12340 ppb
(2340 ppb)
2Sanbornville Water Department
Wakefield, NH
1,5001 of 11580 ppb
(1580 ppb)
Sandown, NH
1881 of 11330 ppb
(1330 ppb)
4River Run Condominiums
Bartlett, NH
6752 of 21075 ppb
(690 to 1460 ppb)
5The Commons of Atkinson
Atkinson, NH
951 of 11020 ppb
(1020 ppb)
6Whispering Brook
Bartlett, NH
301 of 11000 ppb
(1000 ppb)
7Wakefield Engineering
1752 of 2930 ppb
(160 to 1700 ppb)
8Brickyard I Plaza
282 of 2920 ppb
(630 to 1210 ppb)
9Fairfield HO Assoc
Sandown, NH
381 of 1880 ppb
(880 ppb)
10Old Stagecoach Condos
Epping, NH
481 of 1870 ppb
(870 ppb)

Testing Summary for Hydrogen sulfide

Are tests routinely required for Hydrogen sulfide by federal law?No
Water suppliers reporting tests for Hydrogen sulfide (2004-2009):1,025 of 47,576
Average testing rate for water supplier reporting tests (2004-2009):0.3 per year