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Be in the know about nitrate contamination

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What is nitrate?

Nitrate is a naturally occurring chemical compound of nitrogen and oxygen. Nitrate is an essential plant nutrient, often created by the decomposition of plants and animal waste. However, an overabundance of nitrate in the soil, can leach into surface and groundwater. Fertilizer for lawns and cropland, animal manure, and human waste from failing septic tanks, have the potential to contaminate drinking water, causing health problems in babies, the elderly, and people with compromised immunity. 

The Environmental Protection Agency (EPA) has set the Maximum Contaminant Level (MCL) of nitrate as nitrogen (NO3-N) at 10 mg/L (or 10 parts per million) for the safety of drinking water. Nitrate levels at or above this level have been known to cause a potentially fatal blood disorder in infants under six months of age called methemoglobinemia or "blue-baby" syndrome; in which there is a reduction in the oxygen-carrying capacity of blood. The symptoms of blue-baby syndrome can be subtle and often confused with other illnesses. An infant with mild to moderate blue-baby syndrome may have diarrhea, vomiting, and/or be lethargic. In more serious cases, infants will start to show obvious symptoms of cyanosis: the skin, lips or nailbeds may develop a slate-gray or bluish color and the infant could have trouble breathing. A sample of the infant’s blood can easily confirm a diagnosis of blue-baby syndrome. 

What can I do to protect my drinking water?

The first thing you can do is reduce the nitrate inputs on your own property:

  • If you choose to use nitrogen fertilizers, always follow directions and use proper ratios. Extra fertilizer isn't used by your plants and is washed away into the soil and water, which is also a waste of money.
  • If you have animals on your property, manage and compost manure as much as possible, especially in confined areas.
  • Make sure that your septic system is in good working order 

The next important step is to ensure that your well is protected from external contaminants. Although any well can become contaminated by nitrate, shallow, poorly constructed, or improperly located wells are more susceptible to contamination.

Nitrate is not easily detected in drinking water by taste or smell. The only way to know for sure if your drinking water is safe is to have it tested.