Emerging Concern

Pharmaceuticals in Drinking Water

Prescription drugs and over-the-counter medications are increasingly detected in tap water. Wastewater treatment cannot remove them, creating potential for hormone disruption and antibiotic resistance.

What Pharmaceuticals Are Found in Water?

Commonly Detected Drugs

  • Antibiotics (ciprofloxacin, sulfamethoxazole)
  • Hormones (estrogen, testosterone from birth control)
  • Anti-depressants (fluoxetine/Prozac, sertraline)
  • Blood pressure medications (atenolol)
  • Pain relievers (ibuprofen, naproxen)
  • Stimulants (caffeine)
  • Anti-epileptics (carbamazepine)

USGS studies detected pharmaceuticals in 80% of streams tested. Over 100 different drugs and metabolites found.

Health Concerns

  • Hormone disruption: Birth control hormones affect development
  • Antibiotic resistance: Low-level antibiotic exposure creates resistant bacteria
  • Developmental effects: Impact on children poorly understood
  • Cumulative exposure: Multiple drugs at low levels - cocktail effects unknown
  • Aquatic life impacts: Fish feminization, behavioral changes

Important: Levels detected are very low (parts per trillion to billion). Long-term health effects of chronic low-level exposure to multiple pharmaceuticals remain uncertain. More research needed.

EPA Regulation Status

Currently Unregulated: EPA has not set maximum contaminant levels for pharmaceuticals in drinking water. These are "emerging contaminants" under evaluation.

EPA has added some pharmaceuticals to Contaminant Candidate List (CCL) for potential future regulation. Standard water treatment does not effectively remove most drugs.

How Pharmaceuticals Get Into Water

  • 1.
    Human excretion: Unmetabolized drugs pass through body into sewage
  • 2.
    Improper disposal: Flushing unused medications down toilet
  • 3.
    Wastewater treatment inadequacy: Plants not designed to remove pharmaceuticals
  • 4.
    Agricultural runoff: Veterinary drugs from livestock operations
  • 5.
    Recycled water: Treated wastewater becomes drinking water source downstream

Most Affected Areas

  • • Communities downstream of wastewater treatment plants
  • • Densely populated urban areas
  • • Rivers and streams with low flow (high wastewater percentage)
  • • Areas near pharmaceutical manufacturing facilities
  • • Communities near large hospitals

Detection more common in surface water sources than groundwater.

Testing & Removal

Testing

Not routinely tested by utilities. Specialized testing available from research labs ($500+). Most people don't test for pharmaceuticals.

Removal Methods

1. Reverse Osmosis - 85-99% removal

Most effective for broad spectrum of pharmaceuticals

2. Activated Carbon - 50-90% removal

Varies by drug type. Granular carbon more effective than carbon block

3. Nanofiltration - 85-95% removal

Advanced membrane technology. Not common for home use

Note: Standard water filtration and boiling do NOT remove pharmaceuticals.

What You Can Do

  • • Never flush medications down toilet or drain
  • • Use drug take-back programs for disposal
  • • Install reverse osmosis for drinking water
  • • Advocate for advanced wastewater treatment in your community
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