Arsenic in Drinking Water in Florida
What residents of Florida need to know about arsenic in drinking water — including natural geological sources, private well risk, which utilities have documented violations, and how to remove arsenic from tap water.
Source: EPA SDWIS, Florida Department of Environmental Protection, USGS · Last reviewed: 2025-01-01
Quick Answer
Is arsenic in drinking water a concern in Florida?
Arsenic is a moderate concern in Florida, primarily in areas drawing from the Floridan Aquifer System in certain geological settings and in parts of the state with historical phosphate mining. Central Florida's phosphate mining region — Polk, Hillsborough, Manatee, and Hardee counties — can have elevated arsenic associated with phosphate rock chemistry. The deep Floridan Aquifer generally has low arsenic, but shallow aquifer systems in some areas can have higher concentrations.
Where does arsenic come from in Florida's water?
Phosphate mining-associated arsenic in central Florida's Bone Valley phosphate district is one pathway. Naturally occurring arsenic in surficial and intermediate aquifer systems in some regions is another. Private wells in agricultural areas of central and southwest Florida where phosphate mining has occurred, and shallow wells in areas of reducing groundwater chemistry, face the highest risk.
What should Florida residents know?
Private well owners in Polk, Hillsborough, Manatee, Hardee, and DeSoto counties in the phosphate mining region should test for arsenic. Florida FDEP monitors public water systems, but private well owners — about 15% of Florida's population — have no regulatory protection. The state's large retiree population and health-conscious demographics make arsenic awareness important.
Key Facts
| EPA MCL | 10 µg/L (10 ppb) |
| MCLG | Zero |
| Primary source | Phosphate mining geology in central Florida (Bone Valley district); reducing aquifer conditions in some regions |
| High-risk counties | Polk, Hillsborough, Manatee, Hardee, DeSoto (phosphate district) |
| State regulator | Florida Department of Environmental Protection (FDEP) |
| Health effects | Bladder, lung, skin cancer; cardiovascular; diabetes |
| Effective treatment | Reverse osmosis (NSF/ANSI 58) or activated alumina |
Why Arsenic Matters in Florida
Florida's phosphate mining industry — centered in the Peace River Valley — has historically been associated with arsenic occurrence in soils and groundwater due to the arsenic content of phosphate rock. The 'Bone Valley' phosphate district in Polk, Hillsborough, and Manatee counties has documented elevated arsenic in some local groundwater. Florida's intensive agricultural use of phosphate fertilizers may also contribute to shallow groundwater arsenic in farming regions. The state's generally low topography and high water table mean arsenic can mobilize readily from soils into shallow wells.
Florida Arsenic Program
Florida DEP monitors arsenic under federal SDWIS. Florida's Coastal Plain geology generally produces lower arsenic groundwater than states with hard rock aquifers, though the Floridan Aquifer has localized arsenic in some areas. Arsenic is a lower-priority concern for most Florida residents compared to PFAS and disinfection byproducts.
Largest Florida Water Utilities
No arsenic violations on record in EPA SDWIS for Florida utilities in our database. Browse the largest utilities to review their full water quality record.
How Does Arsenic Get Into Drinking Water?
Arsenic in drinking water is almost always naturally occurring — it leaches from arsenic-bearing rocks and minerals into groundwater over time. New England granite, Southwest volcanic geology, and Upper Midwest glacial aquifers are the primary high-risk formations. It has no taste, odor, or color.
Full arsenic overview — geology maps, health effects, all 50 statesWho Should Pay Closest Attention
Polk, Hillsborough, Manatee, Hardee, and DeSoto county residents using private wells near phosphate mining and processing areas, agricultural areas of central and southwest Florida, and private well users throughout rural Florida should consider arsenic testing.
Private well owners near mining districts or agricultural areas
Residents in states with documented volcanic or geothermal geology
Long-term consumers of water from small groundwater systems
Households in homes built before 1960 with older well casings
Residents whose well water has never been tested for arsenic
Anyone living in a state where bedrock wells are common
How to Check Your Situation in Florida
- 1
Identify your water source. If you use a public utility, use the ZIP lookup on this page to find your system and check its compliance record.
- 2
If on public water, review your utility's most recent Consumer Confidence Report (CCR) for arsenic monitoring data. The MCL is 10 ppb — your report should show recent test results.
- 3
If on a private well, order an arsenic test from a Florida Department of Environmental Protection-certified laboratory. A basic arsenic test costs $15–$40. The state agency website maintains a certified lab list.
- 4
Test your well at the tap — not just at the wellhead. The entire water distribution system within your home can affect water quality.
- 5
If your test shows arsenic above 5 ppb, install certified treatment immediately. If above 10 ppb, do not use the water for drinking or cooking until treatment is installed.
- 6
Retest after installing treatment to confirm it is working as certified. Replace filter media on the manufacturer's schedule — an exhausted filter may not perform as rated.
Treatment Options for Arsenic
Boiling does not remove arsenic — it concentrates it. Standard activated carbon filters (Brita, etc.) do not effectively remove arsenic. Certified treatment is required.
NSF/ANSI Standard 58 — Reverse Osmosis
RO systems certified to NSF/ANSI 58 remove 85–95% of arsenic. Under-sink installation. Most effective for removing multiple contaminants simultaneously. Replace membranes and pre-filters on schedule.
Activated Alumina Filters
Activated alumina is specifically designed for arsenic and fluoride removal. Point-of-use or whole-house options available. Must be certified by NSF International or WQA for arsenic reduction. Requires periodic media regeneration or replacement.
Iron/Manganese Oxidation Filters
Effective for arsenic in iron-rich well water, which is common in the Midwest and New England. Oxidation converts dissolved iron and arsenic to a form that can be filtered out. Best when arsenic is co-occurring with high iron levels.
What does NOT work for arsenic
Standard activated carbon filters (Brita, refrigerator filters, most pitcher filters) do NOT effectively remove arsenic. Boiling concentrates arsenic. Water softeners do not remove arsenic. Only use products with NSF certification specifically for arsenic reduction.
Take Action Now
If you use a private well in Florida, test for arsenic — especially if you are in a region with granite, volcanic, or sedimentary geology. A basic arsenic test costs $15–$40 at a state-certified lab.
Public water users: check your utility's Consumer Confidence Report (CCR) for arsenic results. The EPA MCL is 10 ppb — any detection warrants attention.
If arsenic is detected above 10 ppb (or even below it, given MCLG is zero), install an NSF/ANSI 58-certified reverse osmosis system for drinking and cooking water.
Standard carbon filters do NOT remove arsenic — do not rely on a Brita or refrigerator filter for arsenic protection.
Frequently Asked Questions
Related Pages
Arsenic — National Overview
All U.S. utilities with arsenic records
Florida State Overview
All utilities and water quality data
Florida Well Water Guide
Testing, risks & certified labs for private wells
Reverse Osmosis Guide
Removes 85–95% of arsenic
Best Arsenic Filter Guide
What actually works (carbon doesn't)
PFAS in Drinking Water
The 'forever chemical' contamination overview
All Contaminants
Complete reference library
Data Sources & Provenance
All data on this page is sourced from official U.S. government or public datasets.
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Florida Department of Environmental Protection ↗