Fleck PFAS Forever Chemicals Filter

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Hazard Index for Mixtures of Newer PFAS Compounds

Not all PFAS are monitored as a group

The group of chemicals known as PFAS (per- and polyfluoroalkyl substances) includes many individual compounds present at varying levels. The federal monitoring evaluates several specific PFAS chemicals separately, rather than a combined hazard index. These compounds include PFOA, PFOS, PFHxS, PFNA, HFPO-DA, among others. Although collectively called "forever chemicals" due to their persistence, no single index score is reported for mixtures in your water system.

Federal maximum contaminant levels (MCLs) apply individually

Each PFAS compound has a federal MCL, set in nanograms per liter (ng/L) or parts per trillion (ppt). For example, PFOA and PFOS each have an MCL of 4.0 ng/L. This reflects a regulatory threshold, not a household water safety rating or health hazard measure for mixtures.

Differences between UCMR5 and UCMR3 in PFAS Compound Monitoring

Expanded list of PFAS compounds monitored

The latest EPA Unregulated Contaminant Monitoring Rule 5 (UCMR5) survey, covering 2023–2025, includes more PFAS compounds than the previous UCMR3 round. UCMR5 tests additional fluorinated chemicals such as HFPO-DA and PFBS that were not part of UCMR3, offering broader insight into emerging constituents.

Lower detection thresholds under UCMR5

Reporting levels for compounds in UCMR5 are lower than in UCMR3, increasing sensitivity. For example, PFOA and PFOS are reported at 0.004 micrograms per liter (µg/L), equivalent to 4 ng/L. This means the data more reliably captures low-level presence but remains a measurement, not a safety breach.

Role of Plumbing Material and Age Separate from Source Water

PFAS content is measured in source water, not household plumbing

Government data comes from public water system records, representing the water before it reaches household plumbing. Individual plumbing components—such as pipes, fittings, and faucets—do not contribute PFAS but may influence overall water quality in other ways.

Older plumbing may affect other water properties

While plumbing age can influence taste, odor, or levels of metals unrelated to PFAS, it does not affect the presence of fluorinated compounds documented by federal system monitoring.

How PFAS Enter Groundwater or the Distribution System in the Virgin Islands

Environmental sources vary by geographic region

PFAS can originate from historical or ongoing releases such as firefighting foams, industrial activities, or landfill leachate. In the Virgin Islands, public water system records indicate no detections of key PFAS compounds above reporting thresholds during the current federal survey.

Distribution system monitoring captures treatment effectiveness

Sampling points along the public water distribution network, as performed in UCMR5, help characterize if PFAS are present after water treatment. For this Virgin Islands system, no key PFAS compounds were detected above the reporting levels, indicating effective source water quality and treatment.

Judging Treatment Capacity Against Household Daily Water Demand

Estimate your daily water use to select appropriate filter capacity

Households vary widely in water use based on number of occupants, fixtures, and lifestyle. Knowing your typical daily consumption will help ensure sufficient treatment capacity when selecting a filter designed to address fluorinated compounds.

Filters designed to remove PFAS are sized for flow and capacity

The Fleck PFAS Forever Chemicals Filter ships ready to configure and is designed to handle typical household water demands. Matching capacity avoids premature exhaustion and maintains effective reduction of targeted PFAS compounds.

Conclusion

Government records for the WATER AND POWER AUTHORITY-STT public system in the Virgin Islands show no detections above reporting levels for ten key PFAS compounds during the current monitoring cycle, with zero health-based violations recorded. Because local conditions vary, testing your household water for PFAS is the only way to know your specific levels. If you find PFAS present in your water, the Fleck PFAS Forever Chemicals Filter offers a documented solution sized to meet your household's daily water demand.

Where this information comes from

Source: EPA SDWIS public water system record. Sampled 2024-06-24. These figures describe the public water system's record, not the plumbing inside any individual building.

On record: EPA UCMR5 monitoring (2023-2025) for WATER AND POWER AUTHORITY-STT (VI0000443), VI: 40 results across 10 listed contaminants, 0 detections above the reporting level; nothing detected above the method reporting level