Does Reverse Osmosis Remove Glyphosate from Drinking Water?

Does Reverse Osmosis Remove Glyphosate from Drinking Water?

Worried about glyphosate in your drinking water?

Glyphosate is the active ingredient in Roundup, a popular weedkiller. It has come under scrutiny in recent years for its potential health risks. If you are concerned about glyphosate in your drinking water, you may want to consider using a reverse osmosis system.

Reverse osmosis can remove up to 99% of glyphosate from drinking water. RO filters have three types of filters – sediment, activated carbon, and the reverse osmosis membrane. All three of these treatment technologies remove some amount of glyphosate. Integrated into a reverse osmosis system, these three technologies work together to provide the highest level of treatment possible.

Continue reading to learn more about how reverse osmosis works and how well it removes glyphosate.

About Glyphosate

Glyphosate is a broad-spectrum herbicide that is commonly used to control annual and perennial weeds. Although of low toxicity, its presence in drinking water is undesirable and recent evidence links it to serious health concerns.

What is glyphosate

Glyphosate is a broad-spectrum herbicide that is applied to the leaves of plants to kill both grasses and broadleaf plants. It is also used to control aquatic plants. It is the main ingredient in Roundup.

Products containing glyphosate are sold in various formulations, including as liquid concentrate, solid, and ready-to-use liquid. It is used in agricultural, residential, and commercial settings and can be applied with a wide range of methods.

Glyphosate was approved for use in in 1974. It is one of the most widely used herbicides in the United States.

Products that contain glyphosate

There are more than 750 products containing glyphosate for sale in the US. It is the active ingredient in the following herbicides:

  • Roundup – made by Monsanto
  • Rodeo Aquatic Herbicide – made by DowDuPont
  • Eraser – made by Martin’s
  • GroundClear – made by Ortho
  • RM43 Total Vegetation Control – made by Ragan & Massey
  • Ranger Pro Herbicide – made by Monsanto

Health concerns with glyphosate

There is much debate surrounding the use of glyphosate, particularly its perceived health risks.

The US Environmental Protection Agency (EPA) has determined that there are no risks of concern to human health from current uses of glyphosate. They also noted that glyphosate is not an endocrine disruptor.

EPA also found no indication children are more sensitive than adults when exposed at similar levels. Most importantly, EPA found no evidence that glyphosate causes cancer in humans.

However, the International Agency for Research on Cancer (IARC) has determined that glyphosate is “probably carcinogenic”. Some states, like California, have gone so far as to declare it a carcinogenic substance.

Drinking water standard for glyphosate

The Safe Drinking Water Act is the federal law that sets drinking water standards for contaminants in the United States. The EPA established the federal drinking water standard for glyphosate at 700 parts per billion (ppb).

In addition to the federal limit, some states have established stricter standards. Minnesota set their safe limit for glyphosate at 500 ppb. Wisconsin established a standard of 10 milligrams per liter (mg/L) for glyphosate. This is equivalent to 10,000 ppb.

Reverse Osmosisreverse osmosis filter system

Reverse osmosis is a widely used treatment method that reliably removes a wide range of contaminants from drinking water. It is effective at reducing the concentration of many impurities such as lead, PFAS, and heavy metals.

How RO works

Reverse osmosis systems use a semipermeable membrane to filter impurities from water. The membrane allows water to flow through while trapping dissolved solids and other contaminants. The system applies pressure to the water, forcing it through the membrane and removing any impurities.

The membrane is constructed of a semi-permeable polymer that is spirally wrapped around a central tube. The water is forced through the membrane, and the impurities are filtered out. The clean water is then collected on the other side of the membrane, while the contaminants are retained in a concentrated brine. This brine waste is then flushed down the drain.

Reverse osmosis systems can be used to treat both municipal water supplies and private wells. This treatment technology is effective at removing a wide range of contaminants, including salt, bacteria, viruses, pesticides, and more.

RO system components

Reverse osmosis systems typically consist of three modules:

1.   pretreatment

2.   reverse osmosis membrane

3.   post-filter

RO Activated Carbon Filter

Pretreatment protects the membrane from fouling and damage caused by chlorine. It usually consists of a sediment filter and an activated carbon filter. The sediment filter removes particles such as dirt and rust, while the activated carbon filter removes chlorine and other chemicals.

The reverse osmosis membrane is the heart of the system. It’s a thin film composite (TFC) that remove contaminants from water. The TFC is made of several layers of material, including a semi-permeable membrane.

The post-filter is the final stage of filtration that removes any remaining impurities from the water. This is typically a second carbon filter that ensures the water is safe to drink and tastes great. It also includes a particle filter to remove any remaining turbidity.

Some RO systems include a water storage tank, which stores the clean water until you’re ready to use it. This is desirable because the flow rate through the filter is slow. Having a storage tank ensures you can fill a glass or a cooking pot quickly with clean water without having to wait.

How Well Does Reverse Osmosis Treat Glyphosate

Reverse osmosis is very effective at removing glyphosate from water. A properly designed and operated RO system can remove up to 99% of glyphosate from water.

How much glyphosate can reverse osmosis remove

A RO filter system is comprised of three treatment components: a particle filter, activated carbon filter, and the reverse osmosis membrane. All three of these treatment technologies can remove glyphosate from water. Some do a better job than others.

Here is a summary of how each element of a reverse osmosis system can remove glyphosate from drinking water:

  1. Particle filtration: The first element of a reverse osmosis system is the pre-filter unit. This is intended to remove turbidity, suspended solids, and other particles from water to protect the RO membrane from fouling. The US EPA reports that removal of turbidity can effectively remove glyphosate from drinking water. Studies show that a good particle filter can remove 70 to 90% of glyphosate.
  2. Activated carbon filtration: The second element in a reverse osmosis system is the activated carbon filter. Activated carbon filters are commonly used to remove chlorine, taste, and odor compounds from water. Carbon adsorption has been shown to remove glyphosate from drinking water. As much as 92% of glyphosate can be removed with activated carbon.
  3. Reverse osmosis membrane: The main treatment element of your RO system is the membrane. Reverse osmosis has been shown to remove 84 to 99% of glyphosate. Most studies demonstrate 95% or better treatment.

As you can see, each element of a reverse osmosis system can remove some (or all) of glyphosate from water. In combination, these technologies can achieve very high removal rates. In most cases, reverse osmosis systems remove 99% or more of the glyphosate.

Challenges with glyphosate and RO

As we just discussed, a reverse osmosis system uses three modes of treatment to remove glyphosate from drinking water. Each element removes some, but not all, of this herbicide.

If one of the filters stops working, then the overall removal efficiency of the RO system will decrease. The particle filter and carbon filters both have to be replaced every 3 to 6 months. If you don’t change them on schedule, then they will experience “breakthrough”. This is an engineering term that means the filter is no longer able to remove contaminants from water.

The reverse osmosis membrane is a little different. It will last for years, but it can become fouled with time. If the RO membrane becomes fouled, then it will have to be replaced. Fouling can occur if the particle filter and carbon filters are not replaced on schedule.

Test Your Drinking Water for Glyphosate (Roundup)

Glyphosate Water Test
Tap Score has a convenient test kit to measure glyphosate in your drinking water.

Tap Score has a test kit that includes everything you need to test your drinking water for the herbicide glyphosate. They provide the glassware, instructions for sampling your water, and a shipping label to ship the sample to their lab. You’ll get a detailed report of the glyphosate levels in your water and an explanation of what the results mean.

Order your kit today.

Factors to Consider with Reverse Osmosis

If you’re concerned about the quality of your drinking water, a reverse osmosis filter may be a good option for you. RO filters are able to remove a variety of contaminants from your water, including lead, mercury, and chlorine. However, there are a few factors you should consider.

Installation cost of reverse osmosis

Depending on your home’s plumbing, installing an RO system can be relatively simple or quite complex. If your home has a standard under-sink configuration, you can likely install the filter yourself. However, if your home has multiple faucets or you need to drill new holes for the filter, it’s best to hire a professional.

A whole-house RO system can be expensive to install, especially if you have to modify your home’s plumbing. An under-sink unit, on the other hand, can often be installed by a good do-it-yourselfer for a reasonable cost. Each home is unique, so you’ll have to determine which system is right for you.

Maintenance cost

RO filters have sediment filters and activated carbon filters that have to be replaced. A sediment filter will usually last for about six months before it needs to be replaced. Carbon filters have to be replaced every 3 to 6 months, depending on how much water you use and the amount of chlorine in your water.

The cost of replacement filters can vary, but you can expect to spend around $60 to as much as $200 per year on them. Whole house filters are 3 to 4 times as much as under-sink filters.

While this may seem like a lot, it’s important to remember that RO filters can remove a variety of contaminants from your water, making it safer and healthier to drink.

Whole House RO System Diagram

Whole-house versus under-sink units

Another thing to consider is how much water you’ll need to filter. RO filters are typically sized according to the number of gallons they can process per day. If you have a large family or use a lot of water for cooking and bathing, you may need a larger filter.

Reverse osmosis systems are available in a wide range of sizes, from small countertop units to large industrial systems. They can be used for point-of-use (POU) applications, such as filtering water for a kitchen sink, or point-of-entry (POE) applications, such as filtering all the water coming into your home.

Deciding which type of RO system is right for you depends on a number of factors, including your budget, the size of your home, and your water quality. Read my article on under-sink RO systems and whole-house RO systems for a detailed explanation.

NSF certification

Reverse osmosis filter manufacturers often make claims about how well their units remove contaminants. The best way to be certain of their claims is to look for units that have been certified by NSF International.

NSF is an independent organization that tests and certifies products to ensure they meet strict standards for quality and safety. If a product has been certified by NSF, you can be confident it will perform as advertised.

The applicable standard for point-of-use reverse osmosis systems is NSF/ANSI 58. It covers the following parameters:

  • Materials of construction and leaching of harmful substances
  • Mechanical integrity
  • Removal of total dissolved solids (TDS)
  • Efficiency rating
  • Recovery rating
  • Contaminant concentration reduction

Under-sink reverse osmosis filter

Here is the under-sink reverse osmosis filter I installed in my kitchen. You may interested in something similar for your home.

Check Pricing on Amazon


Does activated carbon remove glyphosate

Activated carbon removes glyphosate relatively well, but it is not able to remove 100% of this herbicide. Carbon filters are often placed in line after another treatment method for “polishing”. For this reason, carbon filters should not be used as the only method of treatment if you have glyphosate in your drinking water.

Does boiling water remove glyphosate

When it comes to removing glyphosate from drinking water, boiling is not an effective method. Glyphosate has a high decomposition temperature – much higher than water’s boiling point. This means that when you boil water, you’ll just end up evaporating some of the water and concentrating the glyphosate.

Does a water softener remove glyphosate

Water softeners do not remove glyphosate or any other herbicide or pesticide. Softeners use ion exchange resins that are specifically designed to remove calcium and magnesium. These resins to not remove glyphosate.


So, does reverse osmosis remove glyphosate from drinking water? The answer is a little complicated.

Reverse osmosis can remove up to 99% of glyphosate from water. RO filters have three modes of treatment, and each one of them can remove some of this herbicide from your water. In combination, the combined system can remove 99% of glyphosate from drinking water.

However, there are some challenges that need to be considered when using reverse osmosis to treat glyphosate-contaminated water. These include membrane fouling and the critical maintenance of the particle and activated carbon filters.

Boch Richard

Richard Boch is a chemical engineer responsible for designing water filtration systems for industrial and residential customers. He has more than 20 years of experience with ion exchange, activated carbon, and reverse osmosis. Richard's expertise has made him a go-to source for municipalities and businesses looking to improve their water quality. When he's not working, Richard enjoys spending time with his wife and two young children. You can also follow him on LinkedIn, Twitter and Facebook.

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