This system was not included in federal PFAS monitoring
FYI▾
Should I be concerned?
This system serves fewer than 3,300 people and was not required to participate in EPA UCMR5 testing. Absence of data is not the same as absence of contamination.
Range: 1 to 1.11 mg/L across 2 samples (Jan to Apr 2025).
What is it?
Comes from fertilizer runoff, septic systems, and erosion of natural deposits. One of the most common groundwater contaminants in agricultural areas.
Why it matters
Nitrate above 10 mg/L can cause "blue baby syndrome" (methemoglobinemia) in infants under 6 months — it interferes with blood's ability to carry oxygen. Adults can tolerate higher levels.
What to do
If you have an infant on formula and your water is above 5 mg/L, consider using bottled water for formula preparation. Boiling water does NOT remove nitrate — it concentrates it.
What the research says
Multiple peer-reviewed studies have found neural tube defects, preterm birth, and low birth weight at concentrations as low as 5 mg/L — 2x below the US federal limit.
No additional information available for this contaminant.
Lead & copper — tested at your tap
Copper▸
0.017 mg/L · Jul 2025
Action levellegally enforceable
Sample history
Range: 0.017 to 0.1 mg/L across 3 samples (Jan to Jul 2025).
What is it?
Leaches from copper household plumbing and pipes. Some copper is a normal part of drinking water infrastructure.
Why it matters
Short-term exposure above the action level of 1.3 mg/L can cause gastrointestinal distress. Long-term exposure can cause liver and kidney damage. At typical detected levels (well below the AL), copper is not a health concern.
What to do
If above the action level, run your tap for 30 seconds before drinking. Copper levels decrease as water flows through the pipes.
PFAS
PFOA▸
1.22 ng/L · Oct 2025
MCLlegally enforceable
Sample history
Range: 9.76 to 9.76 ng/L across 5 samples (Jan to Oct 2025).
Peaked at 9.76 ng/L in 2025; the running annual average is now under the 4 ng/L limit.
What is it?
Perfluorooctanoic acid — a "forever chemical" used in non-stick coatings, stain repellents, and firefighting foam. It doesn't break down in the environment or your body.
Why it matters
The EPA set an MCL of 4 ng/L (parts per trillion) in 2024 — one of the strictest drinking water standards ever set. PFOA is linked to cancer, thyroid disease, immune system effects, and reproductive harm.
What to do
A reverse osmosis filter (NSF/ANSI 58) or activated carbon filter (NSF/ANSI 53 certified for PFOA) can reduce levels by 90%+. Pitcher filters with activated carbon provide partial reduction. Utilities have until 2029 to comply with the new MCL.
What the research says
Multiple peer-reviewed studies have found preeclampsia, low birth weight, and immunotoxicity in infants with a dose-response relationship across the range of concentrations found in drinking water.
Range: 6.82 to 6.82 ng/L across 5 samples (Jan to Oct 2025).
Peaked at 6.82 ng/L in 2025; the running annual average is now under the 4 ng/L limit.
What is it?
Perfluorooctane sulfonic acid — a "forever chemical" widely used in firefighting foam, stain repellents, and food packaging. Persists indefinitely in the environment.
Why it matters
MCL of 4 ng/L, same as PFOA. PFOS is linked to cancer, immune suppression, thyroid disease, and elevated cholesterol. It accumulates in the body over years of exposure.
What to do
Same as PFOA — reverse osmosis or NSF/ANSI 53-certified activated carbon filters. Utilities have until 2029 to comply.
What the research says
Multiple peer-reviewed studies have found preeclampsia, reduced birth weight, and impaired immune response in infants with a dose-response relationship across the range of concentrations found in drinking water.
Range: 2.16 to 2.16 ng/L across 5 samples (Jan to Oct 2025).
What is it?
Perfluorohexane sulfonic acid — a shorter-chain PFAS compound found in firefighting foam and consumer products.
Why it matters
MCL of 10 ng/L. Like other PFAS, it persists in the body and environment. Linked to thyroid and immune effects.
What to do
Reverse osmosis filters are most effective for PFAS removal. Activated carbon provides partial reduction.
PFBS▸
ND · Oct 2025
MCLlegally enforceable
Sample history
Range: 8.02 to 8.02 ng/L across 5 samples (Jan to Oct 2025).
What is it?
Perfluorobutane sulfonic acid — a short-chain PFAS compound. Part of the EPA's Hazard Index approach for PFAS mixtures.
Why it matters
Regulated as part of the PFAS mixture Hazard Index, not as a standalone MCL. Short-chain PFAS are harder to remove from water but are excreted from the body faster than long-chain PFAS.
What to do
Reverse osmosis is the most effective removal method for short-chain PFAS.
PFHpA▸
ND · Oct 2025
Sample history
Range: 2.33 to 2.33 ng/L across 5 samples (Jan to Oct 2025).
No additional information available for this contaminant.
PFHxA▸
ND · Oct 2025
Sample history
Range: 3.49 to 3.49 ng/L across 5 samples (Jan to Oct 2025).
No additional information available for this contaminant.
Total PFAS▸
ND · Oct 2025
Sample history
Range: 21.1 to 21.1 ng/L across 5 samples (Jan to Oct 2025).
No additional information available for this contaminant.
WHO recommendation
Manganese▸
0.017 mg/L · Jul 2025
WHO guidelineinternational, unenforced
Sample history
Range: 0.017 to 0.056 mg/L across 3 samples (Jan to Jul 2025).
What is it?
A naturally occurring metal that enters water through eroding rocks and soils, and occasionally from industrial sources. Common in groundwater, especially in some regions of the Midwest and Northeast.
Why it matters
Manganese is essential in small amounts but a developmental neurotoxin at higher exposures. Studies have linked manganese in drinking water to attention and learning difficulties in children, including ADHD, with effects detectable at levels below the EPA's aesthetic standard of 0.05 mg/L. The WHO sets a provisional health-based guideline of 0.08 mg/L; some researchers argue this should be lower. Infants drinking formula made with manganese-rich water may be particularly exposed. EPA's 0.05 mg/L secondary standard exists to prevent black or brown staining on laundry and fixtures — not as a health protection.
What to do
If manganese is at or near WHO's 0.08 mg/L guideline, a reverse osmosis filter certified to NSF/ANSI 58 removes most manganese. Activated carbon and standard pitcher filters do not effectively remove dissolved manganese. For infant formula preparation, parents in areas with detectable manganese may want to use filtered or bottled water — this is what MDH (Minnesota) and several other state health departments now recommend.
What the research says
Multiple peer-reviewed studies have found increased ADHD risk and lower IQ in children, with effects observed in a dose-response pattern from <5 µg/L upward (no clean threshold below which the association disappears) with a dose-response relationship across the range of concentrations found in drinking water.
Source: CURTIS HILL CONDOMINIUM Consumer Confidence Report 2025 · Extracted by WaterScore
3 wells
Water Sources
Tyngsborough pumps water from three groundwater wells drawing from local groundwater. Emergency backup sources are available if primary supplies are disrupted.