Autotrol PFAS Forever Chemicals Filter

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How Hazard Indices Help Evaluate Mixtures of Newer PFAS Compounds

Per- and polyfluoroalkyl substances (PFAS), also known as fluorinated compounds or "forever chemicals," often occur as mixtures in water sources. The hazard index is a way to assess the combined presence of several PFAS compounds by comparing detected levels to reference values without making direct health claims. It helps prioritize which compounds might need attention or further testing based on their relative concentrations and regulatory thresholds.

In Hartford County’s Manchester Water Department system, multiple PFAS compounds have been measured, including PFOA, PFOS, PFHxS, PFNA, and others. Since each compound has a different federal maximum contaminant level (MCL), hazard indices consider these differences to provide a more balanced overview of overall PFAS presence.

Reading Certified Laboratory Test Reports for PFAS Compounds

A certified laboratory report for PFAS lists each compound detected with its concentration, typically in nanograms per liter (ng/L) or parts per trillion (ppt). The report distinguishes which compounds are above the method reporting level — the smallest concentration reliably measured — and details the exact figures found.

For homeowners in Glastonbury, Manchester, South Windsor, Vernon, and Hartford County, such reports clarify whether individual PFAS compounds appear in their water at trace levels. However, these measurements alone do not indicate violation of any safety standard. Only the presence and concentration are reported, while interpretation depends on comparing results to federal standards established for public drinking water.

Understanding 'Detected,' 'Median,' and 'Range' in Manchester Water Department’s Sampling

The EPA’s Unregulated Contaminant Monitoring Rule (UCMR5) data for the Manchester Water Department from 2023 to 2024 show multiple detection events for several PFAS compounds. "Detected" means the test instrument measured a concentration above the reporting level; it is not a legal or health violation.

• PFOA: Detected in 14 of 24 samples, highest 0.013 µg/L (13 ng/L), median of detections 0.0065 µg/L (6.5 ng/L).
• PFOS: Detected in 6 of 24 samples, highest 0.016 µg/L (16 ng/L), median 0.0068 µg/L (6.8 ng/L).
• PFHxS: Detected in 4 of 24 samples, all below the federal MCL of 10 ng/L.

Median indicates the middle value of detected concentrations—half the detected levels are higher, half lower—while range shows the lowest to highest detected value. These statistics provide insight into variability but do not describe any individual home's water.

How Water Source Type and Sample Depth Affect PFAS Expectations

The Manchester Water Department uses surface water sources, which can influence PFAS composition. Surface water tends to have more variable PFAS levels over time and location compared to deep groundwater wells. Consequently, household water from this system may experience fluctuating PFAS concentrations depending on treatment and distribution factors.

Sample depth also affects detection: household taps might show different values due to plumbing materials or residence time in pipes. Therefore, testing a home's water directly is essential to understand specific PFAS levels present.

Interpreting Measured PFAS Ranges Against Federal Standards

The 2024 federal MCL for PFOA and PFOS is 4 ng/L each. Manchester Water Department’s monitoring found some results above this level for these compounds, but this data represents monitoring, not a legal violation record. No EPA health-based violation has been recorded for this system.

It is important to understand that detected values above the reporting level but within or near regulatory limits do not automatically indicate unsafe water. These federal standards serve as benchmarks for long-term exposure and regulatory action, not immediate health hazard declarations.

Ordering the Single Test That Settles Your PFAS Question

For households concerned about PFAS, the definitive step is to obtain a certified laboratory analysis of your specific water supply for the relevant fluorinated compounds. This direct test will provide concentrations at your tap and remove uncertainty about your individual exposure.

To address detected PFAS in home water, the Autotrol PFAS Forever Chemicals Filter offers documented performance by using an Autotrol System designed specifically to reduce a broad range of these fluorinated contaminants. This equipment ships ready to configure, allowing homeowners to tailor their water treatment for PFAS without reliance on external service providers.

Where this information comes from

Source: EPA SDWIS public water system record. Sampled 2024-07-23. These figures describe the public water system's record, not the plumbing inside any individual building.

On record: EPA UCMR5 monitoring (2023-2025) for MANCHESTER WATER DEPARTMENT (CT0770021), CT: 240 results across 10 listed contaminants, 44 detections above the reporting level; 20 results above a 2024 federal MCL