PFAS Contamination on Long Island
Long Island Has a PFAS Problem. Here’s What You Need to Know.
PFAS — per- and polyfluoroalkyl substances — are synthetic compounds engineered with one of the strongest bonds in chemistry. They don’t break down in the environment, they don’t break down in the human body, and they have been accumulating in Long Island’s groundwater for decades. Federal monitoring has documented Long Island’s aquifer system as one of the most PFAS-affected regions in the United States, with contamination traced to Bethpage, multiple military installations, and other industrial sources across Nassau and Suffolk counties. This page explains what PFAS are, where they come from on Long Island, who is most at risk, and what the science says about filtration options — so you can make an informed decision for your household.
The Basics
What Are PFAS?
PFAS — per- and polyfluoroalkyl substances — are a class of more than 12,000 synthetic chemical compounds that share a common structural feature: a chain of carbon atoms bonded to fluorine atoms. This carbon-fluorine bond is among the strongest in organic chemistry, which is precisely why PFAS were developed beginning in the 1940s and became ubiquitous in industrial and consumer applications over the following decades.
PFAS have been used in non-stick cookware coatings (PTFE and related compounds), AFFF aqueous film-forming foam used to suppress fuel fires at airports and military bases, food packaging that resists grease and moisture, stain-resistant treatments for carpets and upholstery, waterproof membranes in clothing, and dozens of manufacturing and industrial processes.
The same property that makes PFAS commercially useful — their extreme chemical stability — makes them an environmental and public health problem. PFAS do not break down through natural weathering, biological activity, or normal chemical processes. They accumulate in soil, travel through groundwater, and concentrate in living tissue. In the human body, certain PFAS compounds accumulate in blood serum, the liver, and kidneys over a lifetime of exposure through drinking water, food, and other pathways. This is why health researchers began calling them “forever chemicals” — they persist indefinitely in both the environment and the body.
Bioaccumulation is the defining long-term concern. Unlike contaminants the body can metabolize and excrete relatively quickly, PFAS compounds with longer chain lengths tend to bind to proteins in the blood and concentrate in organs over years of exposure. Children, because of their smaller body mass and developing organ systems, are thought to be more vulnerable than adults to the health effects associated with a given level of exposure.
Where PFAS Come From
- Grumman / aerospace manufacturing — decades of industrial chemical use at the Bethpage facility, Long Island’s primary historical contamination source
- AFFF firefighting foam — fluorinated foam used at airports, military bases, and industrial fire training sites across Long Island
- Non-stick cookware manufacturing — PFAS-based coatings used in production and discharged during manufacturing processes
- Food packaging — grease-resistant coatings on fast food wrappers, microwave popcorn bags, and other packaging
- Stain-resistant fabric treatment — applied to carpets, upholstery, and outdoor clothing during manufacturing
- Military base operations — AFFF use at Gabreski Airport, Calverton NWIRP, and other Long Island military installations
The History
The Bethpage Story — Long Island’s Ground Zero
The Bethpage contamination site represents decades of industrial activity, regulatory response, and ongoing groundwater migration that continues to affect communities across Nassau and western Suffolk counties.
Grumman Aerospace at Bethpage
Grumman Aerospace Corporation operates military aircraft manufacturing at its Bethpage facility for more than five decades, producing the F-14 Tomcat, the Lunar Module, and other major defense programs. Manufacturing processes involve chromate-based coatings, industrial solvents, and PFAS-containing compounds used in surface treatments and fire suppression systems. These substances are disposed of on-site through practices that were legal at the time but not designed to prevent subsurface migration. Contaminants enter the soil column and begin moving downward toward the Long Island aquifer.
EPA Superfund Designation
The EPA adds the Bethpage facility to the Superfund National Priorities List, initiating formal groundwater monitoring and cleanup planning. Early monitoring focuses on chromium and chlorinated solvents, which are detectable by the analytical methods of the era. The full scope of PFAS contamination in the plume is not yet characterized — the science to measure PFAS at parts-per-trillion concentrations does not yet exist at scale. The plume has already been migrating for decades.
Plume Confirmed Extending into Nassau County Communities
Improved analytical methods and expanded monitoring confirm that the Bethpage plume is not contained at the source site. The contaminated groundwater mass has been migrating eastward and southward through Nassau County for years, affecting public supply wells in multiple communities. PFAS compounds are identified in the plume alongside the previously tracked chromium and solvent contamination. Water authorities in affected communities begin planning treatment upgrades. The plume’s leading edge continues moving eastward toward Suffolk County.
New York State Lowers Its PFAS Drinking Water Guideline
New York State establishes a drinking water standard for PFOA and PFOS, requiring water authorities whose wells exceed the advisory level to take corrective action. The Nassau County Water Authority and Suffolk County Water Authority both face compliance requirements at affected wells. Treatment upgrades at affected supply wells begin accelerating. The state’s standard is more protective than the federal advisory level at the time, and it triggers required responses from Long Island water suppliers.
EPA Establishes First-Ever Federal MCLs for PFAS
The EPA finalizes the first federal maximum contaminant levels for six PFAS compounds. PFOA and PFOS are each regulated at 4 parts per trillion — one of the most stringent drinking water standards in federal history. PFNA, PFHxS, HFPO-DA (GenX), and a mixture rule for additional compounds are also addressed. Long Island water suppliers serving public systems must comply with these standards by 2029. Private well owners are not covered by the MCL requirement and remain responsible for testing and addressing their own supply.
Know Your Risk
Nassau vs. Suffolk: Understanding Your County’s Specific Risk Profile
PFAS risk on Long Island is real across both counties, but the sources, pathways, and affected populations differ significantly between Nassau and Suffolk.
Nassau County
The Bethpage Plume’s Epicenter
- The Bethpage plume is Nassau’s primary source, confirmed migrating east and south through the county’s aquifer zones
- The Nassau County Water Authority (NCWA) has upgraded treatment at multiple affected wells, with ongoing compliance work under the 2024 EPA rule
- Municipal customers in Levittown, East Meadow, Wantagh, North Massapequa, Merrick, and Bellmore areas may have received treated water — but treatment effectiveness varies by well and by specific PFAS compound
- Pre-1986 homes in Nassau carry an additional lead pipe risk on top of PFAS — two separate concerns, each requiring testing to quantify
- Municipal treatment gaps exist between when standards are updated and when equipment upgrades are completed and optimized
Suffolk County
Multiple Sources, Private Well Risk
- Multiple independent contamination sources: Gabreski Airport, Calverton NWIRP, the eastward extension of the Bethpage plume reaching western Suffolk
- The Suffolk County Water Authority (SCWA) has been required to address detected wells, but the SCWA does not serve all Suffolk communities
- Private well owners in Huntington, Smithtown, Kings Park, Hauppauge, and surrounding communities draw directly from the aquifer with no treatment buffer between the contamination source and their tap
- Private well owners are not covered by EPA MCL enforcement — testing and any remediation are entirely the homeowner’s responsibility
- Central and eastern Suffolk PFAS plumes from Gabreski and Calverton are less comprehensively characterized than the Bethpage plume
Municipal treatment helps — but it doesn’t mean your tap is PFAS-free. Treatment efficacy varies by well, by compound, and by the gap between when standards change and when equipment is upgraded and fully optimized. Short-chain PFAS compounds behave differently than the long-chain PFOA and PFOS most equipment is configured to address. A site-specific test tells you what is actually coming out of your tap today — not what the regional average suggests, and not what a plume map implies.
Epidemiological Research
Health Concerns Associated with PFAS Exposure
The following reflects published epidemiological research and regulatory risk assessments. These are documented associations observed in study populations — not guaranteed outcomes for any individual.
Thyroid Disruption
Some PFAS compounds have been associated in epidemiological research with altered thyroid hormone levels. The thyroid regulates metabolism, body temperature, and developmental processes. Associations have been observed in both occupationally exposed populations and in community studies of drinking water contamination.
Immune Suppression
Studies have linked PFAS exposure to reduced vaccine efficacy and suppressed immune response, particularly in children. Research has found that higher PFAS levels in blood serum are associated with lower antibody titers following childhood vaccinations, suggesting interference with immune system development at exposures relevant to drinking water contamination.
Certain Cancers
The EPA’s classification of PFOA and PFOS includes “suggestive evidence of carcinogenic potential” based on animal studies and epidemiological data. Kidney and testicular cancers have been the most consistently observed associations in human epidemiological studies of highly exposed communities, including communities with contaminated drinking water.
Developmental Effects
Research has associated PFAS exposure during pregnancy and early childhood with lower birth weight, altered hormone development, and behavioral effects. Fetuses and infants receive PFAS through placental transfer and breast milk. Children’s developing organ systems may be more sensitive than adults’ to a given level of exposure.
The health associations above are drawn from published epidemiological research and regulatory risk assessments. They represent associations observed in study populations, not guaranteed outcomes for any individual. This information is educational and does not constitute medical advice.
Filtration Options
How Filtration May Help with PFAS — and Why Testing Comes First
The science of PFAS filtration has advanced significantly, but no single approach addresses all compounds equally well. Understanding what’s in your water determines which approach applies to your home.
No home filtration system provides 100% removal of all PFAS compounds under all conditions. The correct system is the one matched to your specific water’s PFAS profile — which requires testing first. The goal is meaningful, measured reduction of the specific compounds present in your water at the concentrations your test reveals. That’s why pHountain conducts a water assessment before recommending any system.
Our Service Area
We Serve Homeowners Across Long Island
Select your town or county for specific local water quality information, local contamination context, and a direct path to your free water test.
Nassau County
Common Questions
PFAS on Long Island — Frequently Asked Questions
Is PFAS in Long Island water actually dangerous?
PFAS compounds have been associated in epidemiological research with thyroid disruption, immune suppression, elevated cholesterol, and certain cancers — particularly kidney and testicular cancer. The EPA established the first federal maximum contaminant levels for PFAS in 2024, setting limits for PFOA and PFOS at 4 parts per trillion, reflecting the agency’s determination that no safe threshold has been established for these compounds. Long Island is one of the most extensively documented PFAS contamination regions in the United States. Whether your specific tap water exceeds these levels depends on your location, your water source, and what treatment your supplier has implemented or is still working toward. The health associations drawn from epidemiological research represent population-level findings, not guaranteed outcomes for any individual.
Does the municipal water authority treat for PFAS?
The Nassau County Water Authority and Suffolk County Water Authority have both upgraded treatment at supply wells where PFAS has been detected above regulatory limits. Both authorities face ongoing compliance obligations under New York State’s standards and will face additional requirements under the 2024 federal MCL rule. However, treatment effectiveness varies by well and by specific PFAS compound. Short-chain PFAS compounds behave differently from the long-chain compounds most treatment equipment is designed to target. Treatment is also not instantaneous — there are gaps between when regulatory standards are updated and when upgraded equipment is fully installed, commissioned, and optimized. Municipal treatment helps, but it does not guarantee that every compound is reduced below every threshold at every tap in the distribution system at all times.
Are private well owners more at risk than municipal customers?
Private well owners face a categorically different risk situation. Municipal customers receive at least some level of treatment and regulatory monitoring, however imperfect. Private well owners draw directly from the aquifer with no treatment and no monitoring. The EPA’s 2024 PFAS maximum contaminant levels apply only to public water systems — private wells are explicitly not covered. In Suffolk County, where private well use is widespread and where contamination sources including Gabreski Airport and Calverton have discharged PFAS into the aquifer, well owners may be drawing water from zones that have never been formally tested. The responsibility for testing and any remediation falls entirely on the homeowner.
What PFAS compounds are most commonly found on Long Island?
PFOA and PFOS are the most extensively documented PFAS compounds in Long Island groundwater, particularly in the Bethpage plume corridor. These are long-chain compounds associated with decades of industrial and military use. Short-chain compounds including PFBS and PFBA have also been detected and present a different filtration challenge. New York State monitoring has identified more than 180 distinct PFAS-related compounds in Long Island groundwater, though individual concentrations and geographic distribution vary substantially. The specific compounds present at any given address depend on proximity to contamination sources, aquifer depth, and groundwater flow patterns — which is why site-specific testing matters more than regional averages.
Does a standard water filter remove PFAS?
It depends significantly on the filter type and the specific PFAS compound. High-performance granular activated carbon (GAC) systems certified to NSF/ANSI 58 or 53 standards have demonstrated meaningful removal of PFOA and PFOS in testing. Standard pitcher filters and refrigerator filters vary widely — some certified systems show reasonable reduction of long-chain PFAS, while basic carbon block filters may offer minimal removal. Short-chain PFAS compounds are more water-soluble and harder for carbon to capture; systems with ion exchange media may be needed for these. No system provides 100% removal of all PFAS under all conditions. The right system is the one matched to the specific PFAS compounds present in your water, which requires testing to determine.
How do I know if my specific address is affected by PFAS?
PFAS concentration is not uniform across Long Island. Plume maps and monitoring data provide regional context, but they cannot tell you what is coming out of your specific tap today. Municipal water quality reports reflect system-wide averages or well-head measurements, not individual tap readings after water travels through the distribution network and your home’s service line. The only reliable way to know your home’s PFAS level is a laboratory-based water test at your address. pHountain provides free in-home water assessments for Long Island homeowners that include PFAS screening alongside a full water quality evaluation. A recommendation only comes after the results — never before.
Free Water Assessment
Find Out What’s Actually in Your Long Island Water
PFAS has no taste. No color. No odor. You cannot detect it through any of your senses, and its health associations build over a lifetime of exposure — not days or weeks. The only way to know your specific levels is to test your specific water.
pHountain’s free in-home water assessment for Long Island homeowners includes:
- PFAS screening for the Long Island aquifer system and known contamination corridors
- Full water quality evaluation including chlorine, nitrates, hardness, iron, and pH
- Clear, plain-language explanation of every result before we leave your home
- Honest assessment — if your water tests within safe parameters, we tell you that clearly and thank you for your time
- A recommendation only if your results indicate a concern — never before
No pressure. No obligation. Just your numbers.
Your Next Step
PFAS Has No Taste. No Color. No Warning. The Only Answer Is a Test.
Long Island’s PFAS contamination is documented, ongoing, and affects both municipal and private well customers across Nassau and Suffolk counties. The only way to know your home’s specific situation is to test. pHountain provides free in-home water assessments with no pressure and no obligation — just your numbers, explained clearly, before we leave.