EPA SDWIS DataMaryland

Nitrite in Maryland Drinking Water

Maryland has 7,992 public water systems. 3891 have recorded nitrite violations.

Total Systems

7,992

With Violations

3,891

EPA MCL

1

Population Served

6.0M

Nitrite in Maryland: Key Facts

Total Water Systems

7,992

Systems with Violations

3,891

Lead Violations

56

Copper Violations

305

EPA Standard

1 mg/L as N

MCLG (goal): 1 mg/L

Water Systems with Violations in Maryland

Health Effects of Nitrite Exposure

Blue baby syndrome

Can block oxygen in blood of infants under 6 months

Methemoglobinemia

Converts hemoglobin, reducing blood oxygen-carrying capacity

Infants below 6 months can develop methemoglobinemia ('blue baby syndrome'). Combined nitrate+nitrite limit is 10 mg/L.

Frequently Asked Questions

Is there nitrite in Maryland water?

Maryland has 7,992 public water systems. 3891 have recorded nitrite violations based on EPA SDWIS data. If you are on a private well, your water is not covered by these regulations and should be tested independently.

How can I check my Maryland water for nitrite?

Search for your water system using the WaterCheck system lookup, or contact your utility and request a copy of your Consumer Confidence Report (CCR). The CCR is published annually and lists all detected contaminants, their levels, and the EPA MCLs. For private wells, contact a state-certified lab for independent testing.

What is the EPA limit for nitrite?

The EPA Maximum Contaminant Level (MCL) for nitrite is 1 mg/L as N. Systems that exceed MCLs are required to notify customers and take corrective action.

Nitrite at a Glance

Categoryinorganic
EPA MCL1 mg/L as N

Source

Runoff from fertilizer use; leaching from septic tanks and sewage; erosion of natural deposits

How to Filter Nitrite

  • +Reverse osmosis removes nitrite
  • +Ion exchange systems can remove nitrite
  • +Do not give water with elevated nitrite to infants