Fleck PFAS Forever Chemicals Filter

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What does the hazard index mean for PFAS mixtures in Pulaski County's water?

The hazard index is a way to consider the combined potential effect of multiple per- and polyfluoroalkyl substances (PFAS) together, rather than looking at each compound separately. While Pulaski County’s public water system, Fort Leonard Wood, has detected very low levels of some PFAS compounds like PFBS, no measurements exceed federal maximum contaminant levels (MCLs). This means that the cumulative presence, the so-called 'hazard index,' is based on detections far below the regulatory thresholds. However, this index does not indicate a health risk by itself—it is a tool used to assess potential concern when compounds are found in mixture and may help guide treatment choices.

Which sources like firefighting foam, textile finishing, or landfills align with the PFAS record for this region?

The public water system in Pulaski County uses surface water, which can be influenced by regional environmental sources such as firefighting foam, textile processing, or landfill leachate. Although the recorded data for PFAS compounds including PFOA, PFOS, and others showed no detections above reporting limits except for one detection of PFBS at a very low nanogram-per-litre level, these sources have historically contributed to PFAS presence in many parts of the country. In Pulaski County, the absence of elevated detections suggests minimal ongoing influence from such sources within the supply area, but presence at very low levels may reflect widespread environmental background rather than a specific local source.

How do public system PFAS records differ from private well testing for what they reveal?

Public water system records, like those for Fort Leonard Wood in Pulaski County, represent comprehensive monitoring of the water leaving treatment plants to many households and therefore reflect the average water quality delivered through the public network. These results do not measure PFAS levels inside an individual home’s plumbing or private well water. Private well owners would need to conduct specific testing of their own water supply to determine the presence and concentration of PFAS locally, since private wells can be influenced by different geologies and point sources not represented in public water system data.

What differences exist between the UCMR5 survey and the previous UCMR3 regarding PFAS monitoring?

The EPA’s UCMR5 survey, which includes data for Fort Leonard Wood, expanded the range of PFAS compounds monitored compared to the earlier UCMR3. UCMR5 looks for nine PFAS compounds such as PFOA, PFOS, PFHxS, PFNA, HFPO-DA, PFBS, and others, at lower reporting levels measured in nanograms per litre (ng/L or parts per trillion). In contrast, UCMR3 targeted fewer PFAS compounds and had different detection thresholds. This means UCMR5 provides a more detailed picture of PFAS occurrence at trace levels, helping residents and decision-makers better understand the variety and levels of 'forever chemicals' that may be present in water systems.

What are the consequences when PFAS in water remain untreated over many years?

Per- and polyfluoroalkyl substances, sometimes called 'forever chemicals,' are persistent in the environment and do not break down easily. Over long periods, untreated PFAS can accumulate in household water. While the Fort Leonard Wood system data show no exceedances of federal limits and no health-based violations, individual homeowners concerned about potential presence of PFAS in their water supply may consider treatment options. Untreated PFAS may affect aesthetic qualities of water or building materials, and some households prefer treatment as a precautionary measure. The choice of treatment equipment can influence how effectively these substances are reduced inside the home.

Why are PFOA and PFOS concentrations reported in nanograms per litre and what does four-decimal precision signify?

PFOA and PFOS levels in Pulaski County’s public water system are reported in nanograms per litre (ng/L), also known as parts per trillion (ppt), because their concentrations are extremely low and require sensitive instruments to detect. Reporting to four decimal places—such as 0.0048 µg/L (4.8 ng/L)—provides precise measurements that help regulators and consumers understand trace presence even when well below federal maximum contaminant levels. This high precision enables detailed monitoring of 'forever chemicals,' supporting informed decisions on water treatment choices and regulatory actions.

What should I not conclude from the PFAS data available for Pulaski County's public water system?

The EPA data for Fort Leonard Wood in Pulaski County shows no health-based violations for PFAS and no concentrations above federal maximum contaminant levels. However, residents should not assume that these findings guarantee the absence of PFAS in every home’s water supply or that private wells share the same water quality. A detection is simply a measurement above an instrument's reporting level—not an indication of a violation or unsafe water. Homeowners interested in understanding their specific water quality should conduct individual testing. Those exploring treatment options for PFAS reduction may consider equipment such as the Fleck PFAS Forever Chemicals Filter, which ships ready to configure for residential use and is designed to address a broad range of fluorinated compounds documented in water systems.

Where this information comes from

Source: EPA SDWIS public water system record. Sampled 2025-06-11. These figures describe the public water system's record, not the plumbing inside any individual building.

On record: EPA UCMR5 monitoring (2023-2025) for FORT LEONARD WOOD (MO3079500), MO: 320 results across 10 listed contaminants, 1 detections above the reporting level; compared with the applicable federal MCL, none above