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    Drinking & Cooking Water Safety

    Is Your Drinking Water
    Actually Safe?

    Your tap water travels through miles of aging infrastructure before reaching your glass. What it picks up along the way could be affecting your health right now.

    300+
    Contaminants Found in U.S. Tap Water
    160+
    Unregulated Contaminants
    30M+
    Americans Served Violating Water
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    Buy a WaterVo machine ($599+) and we'll refund your $99 testing fee. Just send us your receipt!Learn More
    The Science

    Why You Can't Trust Your Tap Without Testing

    The EPA regulates only 90 contaminants in drinking water — but over 300 have been detected in U.S. tap water. Your utility's annual Consumer Confidence Report tests water at the treatment plant, not at your tap. What happens between the plant and your glass matters.

    9.2M
    Lead Service Lines
    Still delivering water to American homes. The EPA's Lead and Copper Rule Improvements (2024) require replacement within 10 years.
    49%
    Tap Water Contains PFAS
    USGS study found PFAS in nearly half of all U.S. tap water samples. The EPA set first-ever enforceable limits in April 2024.
    700+
    Disinfection Byproducts Identified
    Only 11 are regulated. DBPs form when chlorine reacts with organic matter in your pipes and are linked to bladder cancer.

    EPA vs. WHO Standards Comparison

    The EPA and WHO often set different limits for the same contaminants. In many cases, health-based goals are significantly stricter than enforceable maximums — meaning "legal" doesn't always mean "safe."

    ContaminantEPA MCLEPA MCLGWHO Guideline
    Lead15 ppb (AL)0 ppb10 ppb
    PFOA4 ppt0 ppt100 ppt
    PFOS4 ppt0 ppt100 ppt
    Arsenic10 ppb0 ppb10 ppb
    THMs (total)80 ppbN/AVarious
    Nitrate10 ppm10 ppm50 ppm
    Chromium-6100 ppb (total Cr)Under review50 ppb

    MCL = Maximum Contaminant Level (enforceable). MCLG = Maximum Contaminant Level Goal (health-based, non-enforceable). AL = Action Level.

    Deep Dive

    Key Contaminants in Drinking Water

    Explore the most critical contaminants found in U.S. drinking water. Each card includes EPA/WHO limits, health effects, and the science behind the risk.

    Lead (Pb)

    9.2 million U.S. homes have lead service lines

    EPA Limit
    15 ppb (action level)
    WHO Guideline
    10 ppb

    Health Effects

    • Irreversible neurological damage in children
    • Kidney damage and hypertension in adults
    • Developmental delays and learning disabilities
    • No safe level of exposure established by CDC

    PFAS (Forever Chemicals)

    49% of U.S. tap water contains detectable PFAS

    EPA Limit
    4 ppt (PFOA/PFOS, 2024 rule)
    WHO Guideline
    100 ppt (provisional guideline)

    Health Effects

    • Linked to kidney and testicular cancer
    • Thyroid disease and immune suppression
    • Reproductive issues and developmental effects
    • Liver damage at chronic low doses

    Chlorine & Disinfection Byproducts

    98% of U.S. municipal water is chlorinated

    EPA Limit
    4 ppm (chlorine); 80 ppb (TTHMs)
    WHO Guideline
    5 ppm (chlorine); 100 ppb (THMs)

    Health Effects

    • Trihalomethanes (THMs) linked to bladder cancer
    • Haloacetic acids associated with reproductive issues
    • Chloramine can cause digestive issues
    • Taste and odor complaints at >1 ppm

    Microplastics

    83% of tap water samples worldwide contain microplastics

    EPA Limit
    No federal standard
    WHO Guideline
    No guideline (under review)

    Health Effects

    • Inflammatory response in gut tissue
    • Potential carrier for absorbed chemicals (BPA, phthalates)
    • Nano-plastics can cross cellular membranes
    • Long-term effects still under active research

    Bacteria & Pathogens

    7.2 million illnesses/year from waterborne pathogens in U.S.

    EPA Limit
    0 CFU/100mL (total coliform rule)
    WHO Guideline
    0 CFU/100mL (E. coli)

    Health Effects

    • Gastrointestinal illness (E. coli, Giardia)
    • Legionnaires' disease from Legionella in plumbing
    • Cryptosporidium resistant to chlorine disinfection
    • Severe risk for immunocompromised individuals

    Nitrates & Nitrites

    22 million Americans exposed to elevated nitrates

    EPA Limit
    10 ppm (nitrate-N); 1 ppm (nitrite-N)
    WHO Guideline
    50 ppm (nitrate); 3 ppm (nitrite)

    Health Effects

    • Blue baby syndrome (methemoglobinemia) in infants
    • Associated with colorectal cancer risk
    • Thyroid disruption at chronic exposure
    • Agricultural runoff is primary source
    Cooking Safety

    How Contaminated Water Affects Your Food

    Cooking doesn't eliminate water contaminants — in many cases, it concentrates them. Understanding how water interacts with food preparation is essential for protecting your family.

    Boiling Concentrates Contaminants

    Boiling water removes pathogens but actually increases the concentration of lead, nitrates, PFAS, and other chemical contaminants as water evaporates. A pot boiled down by 50% doubles the contaminant concentration.

    Coffee & Tea Absorb More Lead

    Hot water leaches lead from pipes 2–5x faster than cold water. Studies show tea prepared with lead-contaminated water absorbs additional lead into the leaves, increasing total intake by up to 80%.

    Pasta & Rice Absorb Water Chemicals

    Foods cooked in water absorb up to 60% of waterborne contaminants. Rice is particularly efficient at absorbing arsenic and PFAS from cooking water, according to FDA studies.

    Baby Formula — Highest Risk

    Reconstituted formula is an infant's sole nutrition source. Lead, nitrates, and PFAS in water used for formula preparation pose the greatest risk to developing brains and immune systems.

    Health Impact

    Who's Most at Risk?

    Contaminant exposure doesn't affect everyone equally. These populations face disproportionate risk from drinking water contamination.

    Infants & Young Children

    6x more vulnerable

    Children drink 2.5x more water per pound of body weight than adults. Lead exposure at any level causes irreversible IQ reduction — an estimated 3–5 IQ points lost per 5 ppb increase in blood lead.

    Pregnant Women

    Critical exposure window

    PFAS exposure during pregnancy is linked to low birth weight, preeclampsia, and developmental delays. Nitrate exposure above 5 ppm is associated with neural tube defects and preterm birth.

    Elderly & Immunocompromised

    Reduced detox capacity

    Aging kidneys and livers process contaminants less efficiently. Cryptosporidium and Legionella pose severe, potentially fatal risks to those with weakened immune systems.

    Chronic Exposure (All Ages)

    Cumulative lifetime risk

    Many contaminants like PFAS, arsenic, and DBPs accumulate over years. Cancer risk calculations are based on 70 years of daily exposure — the effects are rarely immediate but deeply consequential.

    Lab Process

    Inside the Lab: How We Analyze Your Water

    Our certified lab partner uses EPA-approved analytical methods — the same techniques employed by municipal water systems and regulatory agencies.

    Analytical Methods

    EPA 200.8ICP-MS for metals (lead, arsenic, chromium, copper, mercury)
    EPA 537.1LC-MS/MS for PFAS compounds at parts-per-trillion
    EPA 524.2GC-MS for volatile organic compounds and THMs
    SM 9223BColilert method for E. coli and total coliform bacteria
    EPA 300.1Ion chromatography for nitrate, nitrite, fluoride, sulfate
    MicroscopyParticle count and identification for microplastics

    Microscopy Image Placeholder

    Microscopy analysis of water sample

    High-resolution imaging coming soon

    Take Action

    Know What's in Your Water

    Our comprehensive $99 test kit analyzes 100+ contaminants using EPA-certified methods. Get clear, actionable results with a personalized report and free consultation.

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