The Power of Information

National Drinking Water Database


Total trihalomethanes (TTHMs) in Florida


Total trihalomethanes constitute the sum of four disinfection byproducts: chloroform, bromodichloromethane, dibromochloromethane, and bromoform. [read more]

The Most Polluted Communities in Florida

1,707 water utilities reported detecting Total trihalomethanes (TTHMs) in tap water since 2004, according to EWG's analysis of water quality data supplied by state water agencies

Ranked by highest average Total trihalomethanes (TTHMs) level

RankSystem Population Served Positive test results of total reported tests Average Level
(Range)
1Horseshoe Beach Wtp
Horseshoe Beach, FL
8202 of 2168.5 ppb
(144 to 193 ppb)
2Harmony Cdd
St. Cloud, FL
82518 of 18162.03 ppb
(92.5 to 204 ppb)
3Martin Correctional Institution
Indiantown, FL
1,3007 of 7150.88 ppb
(0.19 to 228 ppb)
4Jones' Trailer Park
Miami, FL
1208 of 8141.13 ppb
(6.57 to 238.98 ppb)
5San Sebastian Woods
Micco, FL
568 of 8139.85 ppb
(68.8 to 218 ppb)
6Yankeetown Water Dept.
Yankeetown, FL
71117 of 17138.34 ppb
(55.85 to 222.2 ppb)
7Otter Creek Wtp
Otter Creek, FL
12015 of 15130.41 ppb
(4 to 196 ppb)
8Magnolia Village
Edgewater, FL
39416 of 16124.21 ppb
(5.75 to 234 ppb)
9Town of Cross City
Cross City, FL
2,85019 of 19123.68 ppb
(74.76 to 221.41 ppb)
10City of Arcadia Water Dept
Arcadia, FL
8,94216 of 16123.43 ppb
(43.12 to 202.4 ppb)

Health Based Limits for Total trihalomethanes (TTHMs)

StandardDescriptionLevel
One in one million (10-6) Cancer RiskThe concentration of a chemical in drinking water corresponding to an excess estimated lifetime cancer risk of 1 in 1,000,000. Source: U.S. Environmental Protection Agency.9.8 ppb
EPA Human Health Water Quality CriteriaWater quality criteria set by the US EPA provide guidance for states and tribes authorized to establish water quality standards under the Clean Water Act (CWA) to protect human health. These are non-enforceable standards based upon exposure by both drinking water and the contribution of water contamination to other consumed foods. Source: U.S. Environmental Protection Agency.11.5 ppb
Maximum Contaminant Limit (MCL)The enforceable standard which defines the highest level of a contaminant that is allowed in drinking water. MCLs are set as close to health-based limits (Maximum Contaminant Level Goals, or MCLGs) as feasible using the best available analytical and treatment technologies and taking cost into consideration. Source: U.S. Environmental Protection Agency.80 ppb
Lifetime health-based limit, non-cancer riskConcentration of a chemical in drinking water that is not expected to cause any adverse, noncarcinogenic health effects for a lifetime of exposure. The Lifetime health-based limit (or Health Advisory, HA) is based on exposure for a a 70-kg adult consuming 2 liters of water per day. Source: U.S. Environmental Protection Agency.130 ppb
One in ten thousand (10-4) Cancer RiskThe concentration of a chemical in drinking water corresponding to an excess estimated lifetime cancer risk of 1 in 10,000. Source: U.S. Environmental Protection Agency.980 ppb
Drinking Water Equivalent LevelA lifetime exposure concentration protective of adverse, noncarcinogenic health effects, that assumes all of the exposure to a contaminant is from drinking water. Source: U.S. Environmental Protection Agency.1835 ppb
Children's health-based limit for 10-day exposureConcentration of a chemical in drinking water that is not expected to cause any adverse, noncarcinogenic effects for up to ten days of exposure. The Ten-Day health-based limit (or Health Advisory, HA) is typically set to protect a 10-kg child consuming 1 liter of water per day. Source: U.S. Environmental Protection Agency.4860 ppb
Children's health-based limit for 1-day exposureConcentration of a chemical in drinking water that is not expected to cause any adverse, noncarcinogenic health effects for up to one day of exposure. The One-Day health-based limit (or Health Advisory, HA) is typically set to protect a 10-kg child consuming 1 liter of water per day. Source: U.S. Environmental Protection Agency.10600 ppb

Violation Summary for Total trihalomethanes (TTHMs) in Florida

Data from the U.S. Environmental Protection Agency includes the following violations of federal standards in Florida since 2004

Violation TypeNumber of Violations
Over maximum contaminant level, Average893
Monitoring and Reporting Disinfection Byproduct Rule295