Is Your Tap Water Safe? Hidden Drinking Water Contaminants (Part 5)
What’s in U.S. drinking water, how contaminants affect hormones and metabolism, and how to reduce long-term exposure
Water is essential to life—but tap water isn’t always as clean or as safe as we assume.
Yet contaminants can enter the water supply from multiple sources, including industrial pollution, agricultural runoff, aging infrastructure, wastewater discharge, and even the chemical processes used to treat municipal water systems. That’s why tap water contaminants can persist even in systems that meet regulatory standards.
The EPA estimates that more than 77 million Americans may be exposed to drinking water contaminants such as lead, arsenic, disinfection byproducts, fluoride, and pharmaceutical residues (1).
An EWG analysis reported that 22 carcinogens detected in U.S. drinking water may collectively contribute to more than 100,000 cancer cases. Importantly, this work evaluated cumulative risk from multiple contaminants, not single-chemical exposure in isolation (2)
The concern is not a single toxin in drinking water.
It is the combined burden of chemical mixtures. Over time, these exposures can compound oxidative stress, disrupt hormone signaling, alter the gut microbiome, and increase inflammatory load
Chronic, low-dose exposure does not always create immediate symptoms. Instead, it can contribute to fatigue, thyroid dysfunction, fertility challenges, neuroinflammation, skin disorders, immune imbalance, and metabolic strain.
The good news is that awareness creates leverage. The most effective approach starts with knowing what’s in your water and choosing filtration that matches the contaminant category
By understanding what may be present in your drinking water—and how those contaminants influence biological systems—you can take practical, evidence-based steps to test and filter tap water and reduce cumulative exposure.
In Part 5 of this Hidden Toxins series, we examine the most concerning contaminants found in tap water today—including heavy metals, pesticides, pharmaceutical residues, fluoride, disinfection byproducts, radiological elements, and PFAS “forever chemicals.” We also break down how these compounds influence hormones, the gut microbiome, immune function, and detoxification—then outline how to check your local report, what filtration methods remove which contaminants, and how to reduce exposure through drinking, cooking, and shower water.
The Six Most Harmful Contaminants in Drinking Water
Drinking water contamination can occur at multiple points—through industrial discharge, agricultural runoff, aging infrastructure, and even the chemicals used in public water treatment. Among the most concerning and well-documented contaminants are the following (3,4):
1. Heavy Metals: The Hidden Dangers in Your Glass
Heavy metals such as lead, mercury, and arsenic are among the most well-documented drinking water toxins in the United States. Unlike many contaminants that are metabolized and excreted quickly, heavy metals accumulate in tissues over time, increasing cumulative toxic burden.
Heavy metals enter tap water through:
Aging pipes and plumbing systems
Industrial discharge and mining activity
Agricultural chemicals
Naturally occurring mineral deposits in soil and bedrock
Chronic exposure to heavy metals in drinking water has been associated with neurological impairment, kidney and liver damage, cardiovascular disease, endocrine disruption, immune dysregulation, and increased cancer risk. Children and pregnant women are particularly vulnerable due to developmental sensitivity.
Lead in TAp water - A Silent but Serious Threat
Lead contamination most commonly originates from aging plumbing infrastructure, especially in homes built before 1986 when lead pipes, solder, and fixtures were widely used.
Even very low levels of lead in drinking water are considered unsafe.
In children, lead exposure has been associated with:
Reduced IQ and learning disabilities
Developmental delays
Behavioral and attention disorders
In adults, chronic exposure has been linked to:
Hypertension and cardiovascular disease
Kidney damage
Bone demineralization and osteoporosis
Fertility and reproductive dysfunction (5)
Because lead is colorless, odorless, and tasteless, contamination is often undetected without laboratory testing.
Mercury in Drinking water - A Neurotoxin in Your Water
Mercury enters water systems through industrial discharge, coal-fired power plants, mining operations, and atmospheric deposition. While commonly discussed in seafood exposure, mercury can also contaminate surface water and groundwater sources.
Even at low concentrations, mercury is a potent neurotoxin. Chronic exposure has been associated with:
Tremors and impaired motor coordination
Memory loss and cognitive decline
Mood changes and neurological dysfunction
Developmental defects in children (6)
Mercury exposure during pregnancy and early childhood is particularly concerning because the developing nervous system is highly sensitive to toxic insult.
Arsenic in Drinking water - A Naturally Occurring Poison
Arsenic is a naturally occurring element found in bedrock and groundwater in many regions of the United States. Industrial pollution, pesticide use, and agricultural runoff can further elevate levels.
Long-term arsenic exposure in drinking water has been linked to:
Skin, bladder, and lung cancers
Cardiovascular disease
Peripheral neuropathy
Immune dysfunction (7)
Arsenic contamination is especially common in private well water, where routine municipal monitoring does not apply. Geographic testing is essential because arsenic levels vary widely by region.
Heavy metals are among the most biologically disruptive drinking water contaminants because they bioaccumulate. Identifying their presence through water testing and using appropriate filtration is a critical first step in reducing long-term toxic burden.
2. Pesticides and Herbicides in Drinking Water - How Agricultural Runoff Contaminates Your Water
Agricultural chemicals are among the most frequently detected drinking water contaminants in rural and municipal systems. Pesticides and herbicides used to control insects and weeds can leach into groundwater or be carried by runoff into rivers, lakes, and reservoirs—ultimately entering tap water supplies.
Because many of these compounds are chemically stable, standard municipal treatment does not always fully remove them. Chronic exposure to pesticides in drinking water has been associated with endocrine disruption, neurodevelopmental effects, reproductive dysfunction, and increased cancer risk (8).
Pesticides in Drinking Water - Endocrine and Neurodevelopmental Risk
Organophosphates, carbamates, and other commonly used pesticides are designed to disrupt biological systems in insects—but these mechanisms are not species-specific. In humans, chronic low-level exposure may interfere with neurotransmitter signaling and hormone regulation.
Research links pesticide exposure to:
Hormonal imbalance and reproductive dysfunction
Increased risk of certain cancers
Developmental delays and behavioral disorders in children
Early-life exposure is particularly concerning because the endocrine and nervous systems are still developing.
Glyphosate in Tap Water - Persistence and Gut Disruption
Glyphosate, the active ingredient in Roundup, is widely used in industrial agriculture and can enter surface and groundwater through runoff. While more commonly discussed in relation to food exposure, glyphosate residues have been detected in certain water systems—particularly in agricultural regions.
Because glyphosate is water-soluble and heavily applied, environmental persistence raises concern about cumulative low-dose exposure through both diet and drinking water (9).
→ The Dark Side of Food Processing & Engineering
Atrazine: A Hormone-Disrupting Chemical in Your Water
Atrazine is one of the most widely used herbicides in the United States, particularly on corn crops. It is environmentally persistent and frequently detected in both surface water and groundwater.
Atrazine exposure has been associated with:
Disrupted testosterone and estrogen signaling
Reproductive abnormalities
Altered developmental hormone pathways (10)
Because atrazine can interfere directly with endocrine regulation, concerns are heightened for prenatal and early-life exposure.
The Frog Study That Shocked Scientists
In a widely cited 2002 study published in Proceedings of the National Academy of Sciences, Dr. Tyrone Hayes and colleagues demonstrated that atrazine exposure caused male African clawed frogs to develop female characteristics, including ovarian tissue and egg production. Some genetically male frogs became functionally female (11).
The findings showed that atrazine suppressed testosterone and increased estrogen activity in amphibians. While animal studies do not automatically translate to human outcomes, the research reinforced concerns about atrazine’s endocrine-disrupting potential—particularly during critical windows of development.
Key concerns associated with atrazine exposure include:
Endocrine disruption: Interference with estrogen and testosterone balance, particularly during pregnancy
Widespread detection: A 2009 Environmental Working Group analysis identified atrazine in tap water affecting more than 30 million Americans (12)
Reproductive and developmental risk: Associations with menstrual irregularities, birth defects, fertility challenges, and certain cancers
3. Pharmaceutical Residues in Drinking Water: Chronic Low-Dose Exposure
Pharmaceuticals are increasingly detected among modern drinking water contaminants. After medications are excreted or improperly disposed of, many compounds—including antibiotics, hormones, antidepressants, and opioids—pass through wastewater treatment systems without complete removal.
Trace pharmaceutical residues have been identified in rivers, lakes, groundwater, and treated municipal water supplies worldwide. Although concentrations are typically measured in parts per billion or trillion, these substances are biologically active by design. Their presence in drinking water raises concerns about chronic, cumulative low-dose exposure (13).
This exposure pathway is particularly relevant for individuals managing hormone imbalance, gut dysfunction, neurological symptoms, immune dysregulation, or chronic inflammatory conditions.
Antibiotics in Drinking Water - Fueling the Superbug Crisis
Antibiotics enter water systems through pharmaceutical manufacturing discharge, hospital wastewater, human excretion, and agricultural runoff from livestock operations.
Low-level antibiotic residues in drinking water have been associated with:
Disruption of gut microbiome diversity
Selection pressure favoring antibiotic-resistant bacteria
Reduced effectiveness of critical antimicrobial therapies
Altered immune regulation
Antibiotic resistance is recognized by the World Health Organization as a major global public health threat. While drinking water is only one exposure source, environmental residues contribute to cumulative selective pressure within microbial ecosystems.
Hormones in Tap Water - Disrupting the Endocrine System
Hormonal medications—including oral contraceptives, hormone replacement therapies, and anabolic steroids—are excreted in urine and incompletely removed during conventional wastewater treatment.
Even at trace concentrations, synthetic estrogens and other endocrine-active compounds may influence hormone signaling pathways because endocrine systems operate at extremely low physiologic thresholds.
Documented concerns include:
Altered reproductive hormone balance
Early puberty or delayed sexual maturation
Fertility challenges
Thyroid signaling disruption
In aquatic ecosystems, hormone residues have been linked to feminization of fish populations—an environmental signal that these compounds retain biological activity at low concentrations.
Developing endocrine systems in fetuses, children, and adolescents are particularly sensitive to disruption.
Antidepressants and Antipsychotics in Drinking Water - Neurological Wild Cards
Neuroactive medications such as fluoxetine (Prozac), sertraline (Zoloft), and risperidone have been detected in treated water supplies at parts-per-trillion levels.
While concentrations are low, psychiatric medications are designed to modify neurotransmitter signaling. Chronic trace exposure has raised questions about potential long-term neurological effects, particularly during early development.
Research has observed:
Behavioral alterations in aquatic species
Changes in feeding patterns and predator avoidance
Altered stress responses
Human data on chronic environmental exposure remain limited, but the presence of neuroactive pharmaceuticals in drinking water underscores the need for improved removal technologies and responsible disposal practices.
Opioids in Surface and Municipal Water - A New Threat in the Water Supply
With increased prescription and illicit opioid use, compounds such as oxycodone, hydrocodone, and fentanyl have been detected in surface waters and, in some regions, treated municipal systems.
Primary sources include:
Human excretion
Improper medication disposal
Hospital and pharmaceutical waste streams
Although environmental concentrations are low, opioids interact directly with central and peripheral opioid receptors. Chronic trace exposure raises theoretical concerns about subtle neurochemical or endocrine effects, particularly in vulnerable populations.
Responsible medication disposal programs are essential to reducing pharmaceutical contamination in water systems.
4. Fluoride in Drinking Water: Benefits, Risks, and Systemic Exposure
Fluoride is added to municipal drinking water in many countries to reduce dental cavity rates. While topical fluoride exposure can strengthen tooth enamel, systemic ingestion through drinking water introduces broader physiological considerations.
Public health policy focuses primarily on dental outcomes. However, fluoride interacts with endocrine, neurological, and skeletal systems, particularly with long-term exposure (14,15).
Common searches such as ‘Is fluoride in drinking water safe?’ reflect ongoing debate about systemic exposure versus topical dental benefit.
Excessive fluoride exposure has been associated with:
Dental and skeletal fluorosis: Overexposure can cause enamel discoloration and increased bone brittleness.
Pineal gland accumulation: Fluoride can accumulate in calcified tissues, including the pineal gland, with potential implications for melatonin production and circadian regulation (16,17).
Neurodevelopmental effects: Several studies associate higher fluoride exposure with reduced IQ scores and altered cognitive development in children (18,19).
Thyroid signaling interference: Fluoride may compete with iodine uptake and influence thyroid hormone activity, particularly in iodine-deficient populations.
Endocrine systems operate at extremely low physiologic thresholds. As a result, children, pregnant women, and individuals with thyroid dysfunction may be more sensitive to systemic fluoride exposure.
5. Chlorine in Tap Water: Disinfection, Byproducts, and Long-Term Health Effects
Chlorine is widely used in municipal water treatment to eliminate pathogens and prevent infectious disease. Its public health role in reducing waterborne illness is well established. However, chlorine is highly reactive, and when it interacts with organic matter in water, it forms disinfection byproducts (DBPs) (20).
Disinfection Byproducts: THMs and HAAs
When chlorine reacts with decaying vegetation, agricultural runoff, or other organic materials, it produces compounds such as:
Trihalomethanes (THMs)
Haloacetic acids (HAAs)
Epidemiological studies have associated elevated DBP exposure with:
Increased bladder cancer risk
Reproductive complications, including miscarriage and low birth weight
Liver and kidney toxicity
Although regulatory limits exist, cumulative exposure over decades may contribute to increased risk in susceptible populations.
Chlorine and the Gut Microbiome
Chlorine does not distinguish between pathogenic organisms and beneficial microbes.
Chronic exposure to chlorinated drinking water has been associated with:
Reduced microbial diversity
Alterations in beneficial bacterial species
Increased inflammatory signaling
Microbial diversity is increasingly recognized as a marker of metabolic and immune resilience.
Intestinal Barrier Integrity and Immune Activation
Chlorine and its byproducts may influence intestinal barrier function.
Disruption of gut barrier integrity can allow bacterial fragments and environmental toxins to enter systemic circulation, contributing to:
Chronic low-grade inflammation
Immune activation
Increased autoimmune susceptibility
These mechanisms are especially relevant in individuals already managing thyroid disorders, autoimmune conditions, or inflammatory syndromes.
Inhalation and Dermal Exposure
Chlorine exposure is not limited to drinking water ingestion.
Chlorine vapors are inhaled during hot showers and baths
Chlorinated water is absorbed through the skin
Research suggests inhalation and dermal exposure may meaningfully contribute to total chlorine burden, particularly in households without filtration.
→ Detoxification & Environmental Medicine
6. Radiological Contaminants: The Unseen Nuclear Threat in Your Water
Radiological contaminants in drinking water may originate from naturally occurring geological deposits or from industrial, military, and nuclear activities. Unlike conventional chemical pollutants, radioactive elements emit ionizing radiation, which can damage DNA, alter cellular repair mechanisms, and increase cumulative cancer risk over time (21).
Because these contaminants are colorless, tasteless, and odorless, routine testing—not sensory detection—is required for identification.
Radium in Drinking Water - Bone and Cancer Risk
Radium occurs naturally in certain rock formations and can dissolve into groundwater as those formations erode.
Radium behaves chemically similar to calcium. Once ingested, it can accumulate in bone tissue, where it emits radiation internally.
Chronic radium exposure has been associated with:
Increased risk of bone cancer
Elevated leukemia risk
Altered bone remodeling
Cumulative exposure is of particular concern in children, whose skeletal systems are actively developing.
Uranium in Drinking Waterv - Radiological and Heavy Metal Toxicity
Uranium contamination may occur in regions with uranium-rich geology or near mining operations, military facilities, or industrial sites.
Uranium presents a dual risk:
As a radioactive element emitting ionizing radiation
As a heavy metal capable of exerting nephrotoxic (kidney-damaging) effects
Documented concerns include:
Kidney toxicity
DNA damage from radiation exposure
Potential contribution to radon generation in enclosed environments
Private wells in certain geographic regions are at higher risk and may require periodic testing.
Chromium-6 in Water - Industrial Contamination and Cancer Concerns
Hexavalent chromium (chromium-6) is primarily associated with industrial contamination. It gained public attention through high-profile groundwater cases but remains an environmental concern in areas near manufacturing or waste sites.
Chromium-6 exposure has been linked to:
Gastrointestinal cancers
Liver and kidney toxicity
Oxidative stress and DNA damage
Unlike trivalent chromium, which plays a role in glucose metabolism, chromium-6 is recognized as a carcinogenic form of the element.
Tritium and Nuclear Byproducts in Water Supplies
Tritium and other radioactive isotopes may enter water systems through:
Nuclear power generation
Medical isotope disposal
Military or research facilities
Although environmental concentrations are typically low, chronic exposure to radioactive isotopes contributes to cumulative radiation dose.
Long-term concerns include:
Increased mutation risk
Elevated lifetime cancer risk
Because removal of radiological contaminants requires specialized filtration systems such as reverse osmosis or ion exchange, proactive testing is essential in high-risk regions.
7. PFAS in Drinking Water - “Forever Chemicals” and Long-Term Health Risk
Per- and polyfluoroalkyl substances (PFAS) are a large group of synthetic chemicals used for their water-, grease-, and heat-resistant properties. They are found in non-stick cookware, food packaging, firefighting foam, industrial processes, and increasingly in contaminated drinking water sources (22,23).
PFAS are often referred to as “forever chemicals” because they resist environmental breakdown and accumulate in human tissue over time.
What Are PFAS and Why Are They Concerning?
PFAS are persistent, bioaccumulative compounds. Once ingested, they bind to proteins in blood and tissues rather than being rapidly excreted.
Epidemiological studies have associated PFAS exposure with:
Increased risk of kidney and testicular cancers
Thyroid dysfunction
Reproductive hormone disruption
Reduced vaccine antibody response
Impaired fetal growth and developmental effects
Elevated liver enzymes and metabolic changes
Because PFAS elimination from the body can take years, cumulative exposure—even at low concentrations—may progressively increase total body burden.
PFAS in Drinking Water
Contaminated drinking water is one of the most significant exposure pathways for PFAS.
Elevated PFAS levels are most frequently identified near:
Military bases (aqueous firefighting foam use)
Airports
Industrial manufacturing facilities
Waste disposal sites
Conventional municipal water treatment processes do not reliably remove PFAS. Effective reduction typically requires specialized filtration such as activated carbon, ion exchange, or reverse osmosis systems.
Private well users in affected regions are particularly vulnerable because routine municipal monitoring does not apply.
Why PFAS Matter in Chronic Illness
From a functional medicine perspective, PFAS exposure may contribute to:
Disruption of detoxification pathways
Endocrine dysregulation, particularly thyroid signaling
Immune modulation and reduced resilience
Increased inflammatory load
These mechanisms are especially relevant for individuals managing autoimmune conditions, fertility challenges, metabolic dysfunction, or persistent unexplained symptoms.
Common Sources of PFAS Beyond Drinking Water
PFAS exposure is not limited to water. Cumulative contact can occur through multiple everyday products:
Non-stick cookware and bakeware
Waterproof and stain-resistant textiles (including performance fabrics)
Grease-resistant food packaging
Certain cosmetics and long-wear personal care products
Some dental floss brands
Fluorinated ski wax and specialty industrial products
Contaminated municipal or well water supplies
Because exposure is cumulative across air, water, food, and consumer products, reducing contact from multiple sources meaningfully lowers long-term toxic burden.
How to Reduce Drinking Water Contaminant Exposure
While water contamination is widespread, exposure can be significantly reduced through informed filtration, testing, and daily household practices.
Reducing toxic burden begins with identifying contaminants specific to your region and selecting targeted removal strategies rather than relying on generic solutions.
Step 1: Identify What’s in Your Water
Municipal systems publish annual Consumer Confidence Reports (CCR) detailing detected contaminants and regulatory limits. Private well users must test independently.
Independent databases can reveal contaminants present below federal limits but still relevant to long-term exposure risk.
Testing is especially important if you:
Use well water
Live near agricultural or industrial areas
Reside near military bases or airports (PFAS risk)
Live in older homes (lead plumbing risk)
Step 2: Choose Filtration Based on Contaminant Type
Not all water filters remove all contaminants.
Effective filtration depends on matching technology to the contaminant category:
Reverse osmosis (RO): Effective for PFAS, fluoride, heavy metals, uranium, and many pharmaceutical residues
Activated carbon: Reduces chlorine, disinfection byproducts (THMs), some pesticides, and certain PFAS
Ion exchange systems: Target specific heavy metals and radiological contaminants
Distillation: Removes many dissolved solids and metals
Refrigerator and basic pitcher filters may reduce chlorine but often do not remove PFAS, fluoride, or radiological contaminants.
Filtered water should be used for drinking, cooking, infant formula preparation, coffee, and tea.
Step 3: Reduce Shower and Dermal Exposure
Drinking water is not the only exposure pathway.
Chlorine and volatile disinfection byproducts can be:
Inhaled during hot showers
Absorbed through the skin
Shower filters or whole-house filtration systems can reduce inhalation and dermal exposure, particularly in individuals with asthma, eczema, or chemical sensitivity.
Step 4: Limit Plastic and Bottled Water Exposure
Many bottled waters contain microplastics and may leach plastic-associated chemicals, especially when exposed to heat.
Filtered tap water stored in glass or stainless steel containers reduces plastic exposure and is often more environmentally sustainable.
When filtration is unavailable, verified spring water bottled in glass is preferable to plastic-packaged alternatives.
Step 5: Prevent Pharmaceutical Contamination
Improper medication disposal contributes to pharmaceutical residues in drinking water.
Do not flush unused medications or dispose of them in sinks.
Instead:
Use local Rx Take-Back programs
Utilize pharmacy disposal kiosks
Follow FDA-recommended disposal guidance
Reducing contamination at the source protects both local water systems and downstream ecosystems.
Step 6: Lower Total Household Chemical Load
Water exposure does not occur in isolation. Reducing total toxic burden improves resilience.
Practical steps include:
Choosing fragrance-free, low-toxicity personal care products
Avoiding antibacterial soaps containing triclosan
Using hydroxyapatite toothpaste if minimizing systemic fluoride exposure
Reducing reliance on ultra-processed foods packaged in PFAS-treated materials
Cumulative exposure across air, food, water, and consumer products determines total body burden.
Protecting Your Health From Drinking Water Contaminants
Drinking water contamination is not limited to isolated events or rare industrial accidents. It often reflects low-level, cumulative exposure to heavy metals, PFAS, disinfection byproducts, pesticides, pharmaceutical residues, and radiological elements over time.
The goal is not fear—it is precision.
Identifying what is present in your water, selecting appropriate filtration, reducing unnecessary exposure pathways, and lowering total environmental burden can meaningfully reduce long-term risk.
Clean water is foundational to metabolic, hormonal, neurological, and immune resilience. Even modest improvements in filtration and sourcing can decrease cumulative toxic load over decades.
Environmental Exposure and Root-Cause Medicine
At Denver Sports & Holistic Medicine, we evaluate environmental exposures—including drinking water contaminants—as part of a broader systems-based framework.
Chronic symptoms such as fatigue, thyroid dysfunction, hormone imbalance, neuroinflammation, skin disorders, and digestive disruption may reflect layered environmental inputs rather than isolated pathology.
Our clinical approach focuses on:
Identifying environmental contributors to symptom patterns
Evaluating detoxification capacity and metabolic resilience
Reducing ongoing exposure
Supporting restoration of regulatory balance
When water quality is part of the picture, addressing it strategically can reduce total inflammatory and toxic burden.
When Water Quality May Be Affecting Your Health
When persistent symptoms overlap with potential environmental exposures, targeted assessment allows for precise testing, exposure reduction, and restoration of physiologic balance.
You may request a free 15-minute consultation with Dr. Martina Sturm to review your health concerns and outline appropriate next steps within a root-cause, systems-based framework.
Frequently Asked Questions About Drinking Water Contaminants
Is tap water safe to drink in the United States?
Most municipal water systems meet federal regulatory standards. However, regulatory limits do not always reflect cumulative, long-term exposure risk. Contaminants such as PFAS, heavy metals, disinfection byproducts, pesticides, and pharmaceutical residues may still be present at low levels. Reviewing your local water quality report provides clarity on what is specifically detected in your region.
How can I find out what’s in my drinking water?
Municipal systems publish annual Consumer Confidence Reports detailing detected contaminants and regulatory limits. Private well users must test independently. Laboratory testing is the most accurate way to identify heavy metals, PFAS, nitrates, and other region-specific contaminants.
What are the most common contaminants found in tap water?
Common drinking water contaminants include:
Lead and other heavy metals
PFAS (“forever chemicals”)
Chlorine and disinfection byproducts (THMs and HAAs)
Fluoride
Pesticides and herbicides
Pharmaceutical residues
Radiological elements such as radium and uranium
Does boiling water remove chemical contaminants?
Boiling water can kill bacteria, viruses, and parasites. It does not remove heavy metals, PFAS, fluoride, pesticides, pharmaceutical residues, or radiological contaminants. In some cases, boiling may concentrate certain chemicals as water evaporates.
What is the best water filter for removing contaminants?
Effective filtration depends on the contaminant type. Reverse osmosis systems remove fluoride, PFAS, heavy metals, and many pharmaceutical residues. Activated carbon reduces chlorine and certain pesticides. Ion exchange systems target specific metals and radiological contaminants. No single filter removes everything.
Are PFAS in drinking water dangerous?
PFAS are persistent, bioaccumulative chemicals associated with thyroid disruption, immune suppression, reproductive effects, and increased cancer risk in epidemiological studies. Because they remain in the body for years, even low-level exposure may contribute to cumulative burden.
Can water contaminants affect hormones?
Yes. Certain contaminants—including PFAS, atrazine, fluoride, and pharmaceutical residues—can interfere with endocrine signaling. Hormonal systems operate at very low physiologic thresholds, making them sensitive to chronic exposure.
Can chlorine exposure happen through showering?
Yes. Chlorine vapors can be inhaled during hot showers and may also be absorbed through the skin. Inhalation and dermal exposure contribute to total chlorine burden in addition to drinking water ingestion.
Is bottled water safer than tap water?
Not necessarily. Bottled water may contain microplastics and plastic-associated chemicals, and many products originate from municipal sources. Filtration of local tap water stored in glass or stainless steel containers is often a more controlled option.
How often should private well water be tested?
Private well water should typically be tested annually for bacteria and nitrates. Testing for heavy metals, PFAS, and regional contaminants is recommended based on geographic risk factors.
Still Have Questions?
If the topics above reflect ongoing symptoms or unanswered concerns, a brief conversation can help clarify whether a root-cause approach is appropriate.
Resources
Environmental Working Group – Study estimates more than 100,000 cancer cases could stem from contaminants in tap water
Environmental Working Group – EWG Tap Water Database: Chemical mixtures may interact and raise cancer risks
Healthline – 15 Common Water Contaminants and Their Potential Risks
World Atlas – The Six Most Harmful Contaminants in Drinking Water
U.S. Environmental Protection Agency – Basic Information About Lead in Drinking Water
World Health Organization – Mercury in Drinking Water
U.S. Geological Survey – Arsenic and Drinking Water
International Journal of Environmental Research and Public Health – Pesticides in drinking water: a review
IntechOpen – Water resource pollution by herbicide residues
Environmental Working Group – Atrazine: A harmful weedkiller taints tap water for millions in the United States
Proceedings of the National Academy of Sciences – Hermaphroditic, demasculinized frogs after exposure to the herbicide atrazine at low ecologically relevant doses
Environmental Working Group – EWG review of atrazine in tap water
U.S. Geological Survey – Pharmaceuticals in Water
Environmental Health Perspectives – Swallowing the pharmaceutical waters
Science of the Total Environment – Fluoride contamination in groundwater: global review of status, processes, challenges, and remedial measures
U.S. Environmental Protection Agency – EPA will expeditiously review new science on fluoride in drinking water
National Institutes of Health – Study reveals how excessive fluoride affects enamel formation
National Health and Nutrition Examination Survey – Fluoride exposure and sleep patterns among older adolescents in the United States
JAMA Pediatrics – Fluoride exposure and children’s IQ scores: systematic review and meta-analysis
National Institutes of Health – Fluoride exposure: neurodevelopment and cognition
World Health Organization – Chlorinated Drinking Water
U.S. Environmental Protection Agency – Radioactivity in Drinking Water
Environmental Working Group – Interactive map: PFAS contamination crisis across the United States
U.S. Environmental Protection Agency – Fifth Unregulated Contaminant Monitoring Rule Data Summary, January 2025