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How to Remove Nitrates From Water

Scott Winfield
Written by Scott Winfield
Last Updated on

Currently, there are three effective water treatment solutions for removing nitrates from water: distillation, reverse osmosis, and absorption.

1. Distillation

Distillation is one of the most conventional water treatment methods for removing nitrates in water.

Distillation

In industrial-scale distillation, there are two tanks and transfer pipes. The process goes as follows:

  1. The water is heated in the first tank until it turns into vapor.
  2. The vapor is transferred to a second tank.
  3. There, the vapor is condensed and cooled until it returns to a liquid state.

As the distance between atoms increases in the water’s gaseous state, the impurities, including nitrate molecules, have nothing left to hold onto. Once the gas cools down and becomes liquid again, all that’s left is pure water.

While distillation can be effective, it has a major drawback. As it reduces water to just hydrogen and oxygen, it removes essential minerals such as calcium, magnesium, and potassium. This is why its not recommended to drink distilled water everyday.

2. Reverse Osmosis

Reverse osmosis (RO) is one of the most popular and effective water treatment methods for nitrates.

Why Is My Reverse Osmosis Water Flow Slow
A reverse osmosis system

Reverse osmosis systems feature a semipermeable membrane with microscopic pores (usually 0.0001-micron). The devices use pressure to push the incoming water through this membrane. Thanks to the microscopic size of the pores, contaminants that have a small molecular structure, like nitrates, become trapped in the membrane.

Take not that reverse osmosis also has the same disadvantage as distillation: it reduces the mineral levels in water, including beneficial minerals.

3. Absorption

Absorption is a unique process that uses an electrical charge that attracts contaminants with an ionic structure such as lead, arsenic, and nitrates. Then, it traps these contaminants’ molecules in long-lasting bonds.

Nitrates have a negative electrical charge, so the absorbent media that removes these compounds should have a positive charge.

Currently, only a handful of water treatment devices that feature gravity filtration (meaning water pitchers and some countertop filtration units) offer such absorbency in their proprietary technologies. However, the few that do are the best on the market.

The Clearly Filtered Water Pitcher uses this absorption method in its Affinity Filtration technology. The results speak for themselves—the pitcher reduces nitrates with a staggering rate of 99.9%. So, this pitcher is one of your best for nitrate-free drinking water.

How Does Nitrate Contaminate Water?

Nitrogen is an extremely abundant element in nature, and it makes up 78% of the air that we breathe. When this element reacts with water, it forms ammonium, and when it reacts with oxygen, it produces nitrates.

Nitrates are fairly mobile, so they don’t dissolve in water and aren’t absorbed by soil. However, there are plants and bacteria that absorb and recycle nitrates in different forms (sometimes as nitrates and sometimes as harmless nitrogen oxide gas).

However, agricultural practices are the most likely cause of nitrate contamination, especially in US well water. Most fertilizers contain high amounts of nitrates that are pre-dissolved in water.

When the fields are fertilized at the correct time, the plants are likely to absorb the nitrates to a higher extent. However, if the timing is wrong (as stated in a study by the University of Arizona), the pre-dissolved nitrates will run off through the soil and find their way into the area’s water table.

This is why groundwater in agricultural areas is nitrate-rich. The problem also affects municipal water supplies that rely on groundwater, like Arizona’s.

Additionally, human and animal waste contains a lot of nitrogen. The nitrogen in waste is likely to form nitrates in septic systems, and if a septic tank is close to your well or aquifer, it can contaminate your water supply with nitrates.

What Are The Health Effects of Nitrate-Rich Drinking Water?

The EPA regulates the nitrate levels in drinking water because if they’re higher than 10 ppm, it can cause death in children below age six.

Some symptoms of nitrate poisoning in babies are shortness of breath and blue baby syndrome, a condition in which a baby’s skin turns blue due to high nitrate intake and poorly oxygenated blood, also referred to as methemoglobinemia.

Besides its detrimental effects on infants, prolonged nitrate exposure can cause serious problems in adults. The Minnesota Department of Health lists depression, muscle weakness, nausea, increased heart rate, and abdominal cramps as symptoms of nitrate poisoning in adults.

According to public health authorities such as the EPA and the Minnesota Department of Health, research regarding the connection between nitrates in drinking water and the risk of cancer is still inconclusive. However, a 2018 study shows at least a correlation between nitrate presence in water and elevated risk of colorectal cancer.

A 2020 study makes a connection between nitrates and other types of cancer, such as brain tumors and stomach cancer. The study concludes that there’s a link between nitrate dosage in water and stomach cancer. However, it states that “there was an association only between the risk of brain cancer & glioma and colon cancer and nitrate consumption.”

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Scott Winfield
Scott Winfield
My name is Scott Winfield and researching and writing about water filters and other strategies to purify water has become my full time passion in recent years. I'm glad that you found our site and you can look forward to authoritative and well researched content here to help you get the best in water.
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