Although nitrate contamination is generally not a problem in public water systems since the Environmental Protection Agency (EPA) closely regulates the amount of nitrates allowed, nitrate contamination in groundwater is a significant concern for those with private well water.
Fear not! This guide will explain how you can limit your exposure to nitrates in water. And most importantly, how to test for and remove them from your drinking water.
Key Takeaways:
- Ingesting high levels of nitrate in well water may lead to an increased risk of gastric cancer, birth defects, blue baby syndrome, and thyroid disease.
- High nitrate concentration in water can be the result of manure runoff, fertilizer used in fields and lawns, septic tank contamination, and wastewater irrigation.
- Nitrate concentration that exceeds the EPA maximum contaminant level of 10 mg/l is harmful to human health.
- The best method to detect nitrate in water is to use a certified lab test kit that scans for nitrate, nitrite, and ammonia to get a precise concentration level.
- Nitrates can only be effectively removed by water treatment methods including reverse osmosis, ion exchange, and distillation.
What Are Nitrates in Well Water?
Nitrates (NO3-) are compounds that consist of nitrogen and oxygen. Nitrate nitrogen naturally occurs in nearly all rainwater and groundwater supplies, typically at levels below 4 mg/l. However, nitrate can come from many sources, such as urban drainage and agricultural chemicals, which are the main factors leading to increased nitrate levels in groundwater over the last 30 years. When nitrates are present at high levels, they can cause serious health risks.
What Causes Nitrate in Well Water?
Well water comes from groundwater, and nitrates can enter this water through leaching from soil or the erosion of rocks under the ground. There are a number of sources that lead to elevated nitrates levels:
- Nitrates that are washed out of animal feedlots
- Nitrates from fertilized agricultural fields or lawns
- Wastewater runoff
- Homes with septic tanks close to the well
Natural bacteria in the soil, sewage, and water interact to convert the nitrate to nitrite (NO2−). Irrigation and rainwater are able to carry the nitrate through the soil into our groundwater supply.
What Is a Safe Level of Nitrate in Drinking Water?
The EPA does have a maximum contaminate level (MCL) for nitrate in drinking water, and it is enforceable. The MCL for nitrate levels in water is 10 parts per million (10 mg/L). Although, the EPA does state that when the concentration of nitrate in water is above 3 mg/L, it typically means there is some contamination. You can also check to see if your local health department has any standards for nitrate pollution in drinking water.
What Are the Health Effects of High Nitrates in Water?
There are a number of health risks associated with drinking water that contains too much nitrate or nitrite because it can decrease the transport of oxygen through your body. This can cause health problems, such as:
- Increased heart rate
- Fatigues and dizziness
- Stomach pain
- Headaches
- Increased risk of thyroid disease
- Increased risk for certain types of cancer
Adults who suffer from cardiovascular disease, lung disease, sepsis, and low levels of stomach acid, along with some other health problems, are the ones at an increased risk of suffering negative health effects from nitrate in drinking water.
Although it is generally adults with certain health problems at greatest risk, pregnant women and infants need to be especially cautious of the health effects of nitrate contamination in drinking water.
Birth Defects And Blue Baby Syndrome
Women who are pregnant and infants are particularly vulnerable to high levels of nitrate in drinking water. In fact, it can cause blue baby syndrome, also called methemoglobinemia, in infants. Nitrates lower the ability of the body’s red blood cells to carry oxygen.
However, this generally does not cause a serious problem in adults or children since the cells typically quickly return to normal. But, if a baby drinks infant formula that has been mixed using water with high nitrate concentrations, the baby may develop blue baby syndrome.
If your drinking water does not have a nitrate concentration of 10 mg/L or higher, there should be no lasting effects on your baby. But, if your baby has a brownish-blue skin tone or their fingernail or toenail bed are bluish, inside their mouth or nose is bluish, or there is a bluish color on their lips, it is important to quickly take the baby to the hospital. Blue baby syndrome can occur quickly in some cases and, if serious, may result in a coma or death.
The best way to avoid blue baby syndrome is to have safe drinking water and to avoid giving infants under seven months old vegetables that are high in nitrates. The only way to detect nitrate contamination in drinking water is by testing the water quality.
If you have family members who may be vulnerable to the health risks associated with drinking water that has high nitrate levels, it may be best to use bottled water until you have your water tested for nitrate contamination.
How To Test for Nitrate in Well Water?
You cannot see, smell, or taste nitrate in water. Although public water supplies are tested for nitrates, private wells need to be tested by the owners. It is recommended by the EPA to test your well water for nitrate at least once a year.
You have two options for testing your private well for nitrate-contaminated water. You could purchase a certified lab test or an at-home test. Both of these testing methods have their advantages.
Certified Laboratory Test
A certified lab test is the most accurate method to test for nitrate and nitrite. These tests provide detailed information about the levels of nitrate in your drinking water, as well as other contaminants.
I recommend using the Freshnss Labs water test kit that scans for nitrate, nitrite, and dozens of other contaminants. The kit comes with everything you need to properly collect a water sample. Within 3 business days, you will receive a report with the exact levels detected, any health or plumbing alerts, and the best treatment methods based on your test data.
Laboratory Water Test Kit
Analyzed in a certified laboratory
Includes detailed report with EPA benchmarking and safety concerns
DIY Test Kits
DIY test kits have the advantages of convenience and low cost. A DIY test can probably be purchased for $30 or less. Additionally, these tests often only take minutes to complete. You will take a test strip and dip it in your water. Then, you wait for the amount of time stated in the instructions before comparing the strip to the color chart included in the test to get an idea of the amount of nitrate in your water.
The downside with DIY test strips is they are not very accurate and do not provide the exact contamination levels.
How Do You Remove Nitrates From Well Water?
Nitrates cannot be removed by activated carbon filters since they are chemical compounds that behave similarly to minerals. However, there are several methods you can use to remove nitrate from your drinking water. Here are some of the recommended methods for nitrate removal.
Reverse Osmosis
Reverse osmosis forces water through a semi-permeable membrane which keeps many undesirable ions like nitrate from passing through it and allows only pure H2O molecules. RO is capable of removing over 99% of nitrates from drinking water.
Ion Exchange
Ion exchange is another good method for removing nitrates from your drinking water. This treatment works similarly to a water softener. The water will run through the unit, which contains resin. This resin will exchange chloride ions for nitrate and sulfate ions.
Distillation
Distillation is another common treatment for nitrate contamination. With this method, the water is boiled, cooled, and condensed. The condensed water will not contain any solids, salts, or heavy metals. Distillation will also inactivate any microorganisms.
How To Prevent Nitrates From Contaminating Your Well Water
Although you can use bottled water or treat your drinking water if the nitrate levels are high, it is better to prevent nitrate contamination of your private well water. There are several ways to help prevent nitrate contamination of your water, and we will discuss some of these below.
Test Your Well Water Regularly
You should test your water regularly if you have a private well. It is recommended you conduct a water test for nitrate at least every two years. This water test won’t prevent nitrate contamination, but it will let you know if you have a problem. Then, you may be able to take action to keep nitrate out of your water, and if this is not possible, treat your water.
Have Your Well Professionally Inspected
You should also have your well professionally inspected. An inspector may discover issues with your well, such as problems with the casing, the grout, or a lack of diversion ditches, which, if corrected, could help keep nitrate out of your well water.
Build New Wells Away From High-Risk Areas
If you cannot fix the problems causing high levels of nitrate in your drinking water, you may be able to solve the problem by building a new well that is not near any high-risk area, if that is an option. Nitrate can leach into groundwater from sources such as areas containing animal waste or agricultural chemicals, so being further away from such areas may decrease nitrate levels in your water.
Avoid Using Fertilizers and Pesticides Near Well Water
Another way to avoid nitrate pollution is to try not to use pesticides or fertilizer near your well. This is a risk factor you can control yourself.