The science

Proof, not promises.

We don't ask you to take our word for it. Sentry H2O publishes independent lab testing for the systems Mountain Pure Water carries, and the real before-and-after numbers are below — including the one result that came in lower than the rest. Honest data is the whole point.

97.44–99.93%

PFAS reduction where both lab values were quantified — most compounds reached non-detect

0

detectable lead, arsenic or uranium left after under-sink treatment

6.8 → 8.2

pH — minerals added back, not stripped out (lab-tested 6.83 → 8.21)

Non-detect

vinyl chloride after treatment in the East Palestine stress test

Every figure from independent, EPA-certified laboratories — Tap Score / SimpleLab (Tempe AZ, 2024–2025) and Summit Environmental Technologies (East Palestine OH, 2023) — published by Sentry H2O. Independent testing, not an EPA-run test.

Daybreak-area evidence

Owner-identified before-and-after samples

The owner identified these two SimpleLab samples as Daybreak-area city water collected before treatment and after Sentry H2O treatment. They are separate from the Tempe dataset below. The pre-treatment sample was collected February 20, 2026; the post-treatment report does not state a collection date. They are not a same-day controlled trial, so the table reports exact values without inventing reduction percentages.

Arsenic & lead

Not detected after treatment

Pre-treatment arsenic was above SimpleLab's non-enforceable Health Guidance Level

Different dates

So we show raw values, not a made-up percentage

Honesty rule: never invent a reduction from uncontrolled samples

See the full Daybreak-area table
Analyte Owner-identified pre-treatment · MZA3JF Owner-identified post-treatment · 2C4J74 Report note
Arsenic 0.0041 mg/L Not detected Pre-treatment: > HGL (0)
Lead 0.000431 mg/L* Not detected Pre-treatment estimate below reporting limit
Uranium 0.00098 mg/L 0.000164 mg/L*† Pre-treatment: > HGL (0)
Aluminum 0.0479 mg/L* 0.108 mg/L† Post-treatment: > HGL (0.07)

* Estimated value below the reporting limit. † Report 2C4J74 uses PPM; in water, PPM is approximately equivalent to mg/L. Tested by Microbac Laboratories, an independent EPA-certified laboratory. Each full report lists that sample's testing facility, EPA analytical methods, laboratory IDs, and accreditation scope per analyte. Read the privacy-redacted owner-identified pre-treatment report and owner-identified post-treatment report.

How it actually works

See every stage that touches your water.

Multi-stage catalytic carbon — not reverse osmosis. It targets the bad stuff and leaves the good minerals in, with no electricity and no wasted water.

Exploded view of the Sentry H2O filtration stages: a dark granular catalytic-carbon disc glowing warm gold, a cream remineralization disc, and a white optional BioChemGuard disc, with clear water threading through all three

Stage 1 · catalytic carbon

ToxyGuard

Catalytic carbon and reduction media break down chlorine, chloramine, fluoride, lead and arsenic as water passes through. (The PFAS numbers below are measured for the system as a whole.)

Stage 2 · minerals back in

AlkaGuard

Re-mineralizes the water and raises pH slightly — the healthy minerals reverse osmosis strips out are kept in, for a cleaner, rounder taste.

Optional · wells (TriGuard)

BioChemGuard

Optional third stage for wells: a submicron barrier against bacteria, viruses and cysts, right at the tap.

Forever chemicals

Does it remove PFAS?

In the Tempe, AZ city-water report, most PFAS compounds reached non-detect after the under-sink Sentry H2O Wellness System. Where both before and after results were quantified, reductions were 97.44–99.93%.

A glass of faintly cloudy, dull tap water on a warm oak counter After Sentry H2O In the tap

The feeling is the hook — the numbers below are the proof. No claim lives on the image itself.

See the full PFAS table
PFAS compound In the tap (µg/L) After Sentry H2O (µg/L) Reduction
PFOS 0.671 Not detected To non-detect
PFOA 0.00047 Not detected To non-detect
PFBS 0.490 0.00034 99.93%
PFHpA 0.02867 0.00020 99.29%
PFHxA 0.00498 0.00013 97.44%
PFDA 0.0542 Not detected To non-detect
PFNA 0.0011 Not detected To non-detect
PFTeDA 0.00217 Not detected To non-detect

One honest note: on the larger whole-house system, four of the eight PFAS detected in the source water reached non-detect. PFOA fell 47.47%, leaving 52.53% of the measured concentration — the lowest figure in the dataset. We show it because a brand that hides its weakest number hasn't earned your trust.

Percentages use the reports' full-precision values and are rounded to two decimal places.

Heavy metals & inorganics

Lead, arsenic, uranium and more

In the separate Tempe dataset, the untreated report detected arsenic, lead and uranium. Each was below federal enforceable thresholds but above SimpleLab's Health Guidance Level, a health-protective and non-enforceable benchmark. After the under-sink Sentry H2O system, all three were non-detectable.

Arsenic → non-detect Lead → non-detect Uranium → non-detect Fluoride → non-detect Cadmium → non-detect Iron → non-detect Nitrate → non-detect Copper → 96.3% reduced
See the full heavy-metals table
Contaminant In the tap (mg/L) After Sentry H2O (mg/L) Reduction
Arsenic 0.00080 Not detected To non-detect
Lead 0.00030 Not detected To non-detect
Uranium 0.00049 Not detected To non-detect
Fluoride 0.52 Not detected To non-detect
Copper 0.01513 0.00056 96.3%
Cadmium 0.000003 Not detected To non-detect
Iron 0.01076 Not detected To non-detect
Nitrate 0.006 Not detected To non-detect

The good stuff stays

It adds minerals back — it doesn't strip them

Reverse osmosis strips water down to nothing; Sentry H2O's AlkaGuard stage re-mineralizes and gently raises pH for a smoother taste.

pH (acidity)

6.83 8.21

Less acidic, smoother taste

Alkalinity

124 189

More buffering minerals

It's not just what you drink — it's what you cook with. Wellness researcher Dr. Josh Axe has written that cooking with demineralized water "like reverse osmosis water, you can lose up to 60 percent of magnesium or 70 percent of manganese in your food"[1] — a figure that traces back to the World Health Organization's own research on mineral loss from cooking in low-mineral water. AlkaGuard is designed to keep those minerals in the water you cook with, not just the water you drink.

A real-world stress test

Vinyl chloride, East Palestine

A restrained dusk scene near a rail line: freight hopper cars along a bare tree line above a slow, murky creek, with a gloved hand holding a clear glass sample vial for water testing
East Palestine, Ohio, 2023 — after the derailment, a Sentry H2O Wellness System was tested against vinyl chloride, one of the chemicals released.

Non-detect

After the 2023 East Palestine, Ohio train derailment, a Sentry H2O Wellness System was tested by Summit Environmental Technologies against vinyl chloride — one of the chemicals released. Treated water tested non-detect for vinyl chloride.

Plain-language note: the lab also ran control samples where vinyl chloride was added after filtration to verify the instrument — those, by design, read high and don't reflect filter performance. The meaningful result is the treated, un-spiked sample: none detected.

What we haven't tested (yet)

Published lab reports currently cover the under-sink and whole-house systems on city water. The shower filter and portable products don't yet have their own published lab results, and we won't claim numbers we can't back up. The owner reports that Sentry H2O systems are tested to NSF standards; certification documentation is being finalized, so we do not call the systems NSF certified.

Results as reported by the testing labs (PFAS in µg/L; metals and minerals in mg/L; "not detected" = below the lab's detection limit). Tested by independent EPA-certified laboratories. Each full report lists that sample's testing facility, EPA analytical methods, laboratory IDs, and accreditation scope per analyte. Tap Score / SimpleLab, Daybreak area (2026) and Tempe AZ (2024-2025); Summit Environmental Technologies, East Palestine OH (May 2023). Source: Sentry H2O's report summary and linked full lab reports.

[1] Dr. Josh Axe, DC, CNS — "Is Reverse Osmosis Water Good for You? Or Does It Over-Filter?" draxe.com, November 1, 2023.

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