Common Drinking Water Contaminants: What You Need to Know
Not all contaminants are created equal—and not all filters remove them. Whether you're dealing with city water or a private well, understanding which contaminants are common, harmful, and removable is the first step to choosing the right solution.
Categories of Contaminants
Drinking water contaminants typically fall into five main categories:
1. Heavy Metals
- Lead: Often enters drinking water through old pipes or fixtures. Known neurotoxin, especially dangerous for children.
- Arsenic: Naturally occurring in some groundwater. Long-term exposure linked to cancer.
- Chromium-6: An industrial pollutant with potential carcinogenic effects.
- Copper: Can leach from plumbing. High levels cause stomach issues and liver/kidney damage.
2. Microbial Contaminants
- Bacteria (e.g. E. coli): Often from fecal contamination; causes gastrointestinal illness.
- Viruses (e.g. Norovirus): Harder to filter; some systems use UV or advanced purifiers.
- Protozoa (e.g. Giardia, Cryptosporidium): Resistant to chlorine; best removed with submicron filters.
3. Chemical & Industrial Pollutants
- PFAS (“Forever Chemicals”): Persistent in the environment; linked to immune, thyroid, and cancer risks.
- Volatile Organic Compounds (VOCs): Includes solvents, gasoline additives, and pesticides.
- Nitrates/Nitrites: Common in farming regions. Dangerous for infants; linked to “blue baby syndrome.”
4. Aesthetic Contaminants
- Chlorine: Common disinfectant in municipal systems. Affects taste and odor.
- Chloramine: Longer-lasting chlorine alternative. Requires special filters for removal.
- Sediment, rust, or scale: Physical particles that cause cloudiness or staining.
5. Emerging Contaminants
- Pharmaceuticals: Trace amounts of medications like antibiotics and hormones found in water sources.
- Microplastics: Tiny plastic particles from breakdown of packaging and synthetic fabrics.
- Disinfection Byproducts (THMs, HAAs): Formed when chlorine reacts with organic matter.
These are just a few examples, and in reality there are thousands of possible contaminants that can be present in water.
How Do Contaminants Get Into Drinking Water?
- Aging infrastructure (pipes, plumbing, municipal lines)
- Agricultural runoff
- Industrial discharge
- Naturally occurring elements in bedrock or soil
- Household activities (cleaning, flushing, etc.)
Even treated municipal water can contain harmful compounds, especially if the distribution system is compromised or your home has outdated plumbing.
How to Identify What's in Your Water
1. Check the Annual Water Quality Report
If you’re on city water, your utility must publish a Consumer Confidence Report (CCR) every year. This report lists detected contaminants and compares them to legal limits.
2. Test Your Water
For private wells or added peace of mind, use a certified water test kit. Look for kits that test for:
- Heavy metals (lead, arsenic, copper)
- Nitrates/nitrites
- Hardness and pH
- Bacteria
- PFAS and VOCs (advanced testing)
We recommend Tap Score from SimpleLab for thorough, certified lab testing.
Matching Filters to Contaminants
Not all filters remove the same things. Here are some general rules of thumb:
| Contaminant Type | Filter Type Needed |
|---|---|
| Lead, arsenic, fluoride | Activated alumina, reverse osmosis, specialty cartridges |
| PFAS, VOCs | Activated carbon + RO or ion exchange |
| Bacteria & protozoa | Submicron ceramic, UV, NSF P231-certified systems |
| Chlorine & chloramine | Catalytic carbon or KDF media |
| Nitrates/nitrites | Anion exchange or RO |
| Sediment, rust, scale | Polypropylene or ceramic pre-filters |
Always check for NSF/ANSI certifications to verify removal claims.
Final Thoughts
Understanding the source and nature of your water contaminants is the key to choosing the right filtration system. At The Filterium, we prioritize transparency, testing, and certifications—so you can drink with confidence.
Next Step:
Ready to tackle your water concerns? Browse our products or explore more guides in the Learn section.