High Risk

Nitrates in Drinking Water

Nitrates from agricultural fertilizers cause life-threatening blue baby syndrome in infants and increase cancer risk. Common in farming regions. Never use nitrate-contaminated water for baby formula.

What are Nitrates?

Nitrates are nitrogen-oxygen compounds essential for plant growth. While naturally present at low levels, human activities (fertilizers, animal waste) have dramatically increased nitrate contamination in groundwater, especially in agricultural areas.

Critical for Parents: Nitrates cause methemoglobinemia (blue baby syndrome) in infants under 6 months. This is a medical emergency. Over 5 million Americans drink water exceeding EPA nitrate limits.

Health Effects

Infants (CRITICAL RISK)

  • • Blue baby syndrome (methemoglobinemia)
  • • Reduced oxygen in blood
  • • Shortness of breath, lethargy
  • • Can be fatal if untreated
  • • Highest risk under 3 months

Adults & Children

  • • Increased colorectal cancer risk
  • • Thyroid disease
  • • Neural tube defects in pregnancy
  • • Hormone disruption

EPA Maximum Contaminant Level

EPA MCL & MCLG
10 mg/L
as Nitrogen (Nitrate-N)

Based on preventing blue baby syndrome. Some health advocates argue it should be lower to address cancer risk.Pregnant women and parents of infants should aim for levels as close to zero as possible.

How Nitrates Get Into Water

  • 1.
    Agricultural fertilizers: Rain washes nitrogen from fields into groundwater
  • 2.
    Animal feedlots: Livestock waste from concentrated operations
  • 3.
    Septic systems: Leaking or failing systems near wells
  • 4.
    Manure application: Over-application to agricultural land

Most Affected US Regions

High-Risk Agricultural Regions

  • • Corn Belt states (Iowa, Illinois, Indiana, Nebraska)
  • • California Central Valley
  • • Wisconsin and Minnesota agricultural areas
  • • Areas with high-density livestock operations
  • • Rural areas with wells near farms

Seasonal Variation: Nitrate levels often spike after spring fertilizer application and heavy rainfall. Testing twice yearly recommended in high-risk areas.

Testing for Nitrates

When to Test

  • • Pregnant or have infant under 6 months
  • • Private well in agricultural area
  • • Near livestock operations or crop fields
  • • Annual testing for well users in farm regions
  • • After heavy rain or spring fertilizer season

Testing Cost: $15-50

County health departments often offer free well testing. Home test strips available for quick screening ($10-20).

How to Remove Nitrates

Effective Methods

1. Reverse Osmosis

85-95% reduction - Most practical for home use

2. Ion Exchange

90-95% reduction - Requires salt regeneration

3. Distillation

95%+ reduction - Effective but slow

CRITICAL WARNINGS

  • NEVER use nitrate-contaminated water for baby formula
  • BOILING WATER INCREASES NITRATE CONCENTRATION - dangerous for infants!
  • • Standard carbon filters DO NOT remove nitrates
  • • Water softeners DO NOT remove nitrates
  • • If over 10 mg/L, use bottled water for infants immediately
  • • Removing bacteria does not remove nitrates
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