Besides chlorine and minerals, other odd things are floating around in the average glass of tap water, such as pharmaceuticals. Think of ingesting these drugs from a neighbor in the next block or even a stranger within city limits—all this through the drinking water.
Ensuring your drinking water is free from contaminants is crucial for your health. However, traditional water purification methods like sedimentation are not equipped to handle drug traces, which can end up in your faucets. This is where advanced processes like reverse osmosis water filtration, capable of eliminating over 99% of these drugs, come into play. Let’s find out how does reverse osmosis remove pharmaceuticals from water in this guide.
Sources of Pharmaceutical Contamination in Water
Before we begin, learn from where they enter in the first place.
The water you drink is initially taken from rivers, streams, lakes, or reservoirs. After being chlorinated and purified, it is conveyed through pipes directly to your faucets. The wastewater plants are designed to remove industrial impurities, not pharmaceuticals. Therefore, pharmaceuticals run off and enter household water.

The most common sources include:
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Improper disposal of medicines (flushing expired or leftover medicines)
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Human waste contains unabsorbed remnants of medicines
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Veterinary drug use (steroids and antibiotics)
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Growth hormones/antibiotics from factory farms/Concentrated Animal Feeding Operations (CAFOs)
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Residues from healthcare facilities
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Agriculture runoff carrying manure
Potential Health Risks of Pharmaceuticals in Water
Scientists have discovered various drugs in drinking water, including antibiotics, antidepressants, hormones, mood stabilizers, and others. The presence of these antibiotics in the biosphere, if they re-enter the human chain, could lead to antibiotic resistance. This is a serious concern. Additionally, these drugs could pose a threat to infants who consume tap water mixed with formula. These potential health risks should motivate us to take steps to ensure the safety of our drinking water.
The current findings indicate that very low levels of pharmaceuticals pose no health risks to humans. However, the fact that they have been consumed collectively for many years is a cause of concern. The only way to fix the problem is to invest in better water purification treatment that effectively removes these pharmaceuticals.
How Reverse Osmosis Works? 3 Things You Need to Know
Although researchers have not provided conclusive evidence, continuous low levels of drugs should be avoided at all costs. So, does reverse osmosis remove drugs from water? Let’s find out
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Basic Principles of Reverse Osmosis

Before proceeding to reverse osmosis, it is important to understand what osmosis is. The process of osmosis is described as the movement of a solvent, like water, from a dilute solution to a concentrated solution. This flow through a semipermeable membrane continues until the two solutions reach the same concentrations. It is a passive transport, as no force is applied to bring equilibrium.
Unlike simple osmosis, reverse osmosis is a process that needs additional pressure as a method of separating solutions. Because the molecular size of the contaminants is higher than that of water, only water is forced to pass through the layer of the semipermeable membrane. Moreover, applying more pressure improves the efficiency of reverse osmosis in removing contaminants from water as more solvent particles will be forced to move through the membrane.
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Components of an RO System
After understanding the basic principle of reverse osmosis, a question arises: How does reverse osmosis remove pharmaceuticals and impurities from water? For this, you need to understand the structure of the RO system.
Let’s take an example of the SimPure RO filtration system, which incorporates pre-filter, RO membrane, carbon filters, and post-filters to remove drugs and other impurities from water. The pre-filter, also known as a sediment filter, is the initial process that filtrates sediment, debris, rust, and chlorine out of the water.
The filtered water is then subjected to pressure, helped by a semipermeable membrane that removes dissolved solids. It is important to note that the reverse osmosis membrane consists of a pore size of only 0.0001 microns, thus denying passage to the majority of contaminants.
Another common type of filter present in most whole-house systems is a carbon filter. This filter is efficient in getting rid of chlorine, VOCs, and other materials that alter the taste and smell. Some systems feature a post-filter, ensuring no particles are left and promoting an even better taste and smell.
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Types of contaminants removed by reverse osmosis
Reverse osmosis effectively removes the following:
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Sediments (debris, rust, sand)
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Organic matter (volatile organic compounds, pesticides, herbicides)
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Microorganisms (bacteria, viruses, protozoa)
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Pharmaceutical residues
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Dissolved minerals
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Asbestos
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Metals (fluoride, chromium, lead, mercury)

Does Reverse Osmosis Remove Pharmaceuticals/Drugs from Water?
Yes, reverse osmosis does remove pharmaceuticals from water. Let’s find out the removal rate.
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Effectiveness of RO in removing pharmaceuticals
The WHO reported that the current wastewater treatment technique at the municipal level does not remove pharmaceuticals from water. Even the most effective techniques, including ozonation, photolysis, and ultrasound, can remove only 20-60% of pharmaceutical residuals.
But thankfully, there is some light at the end of the tunnel. NACWA and AMWA, amalgamating into one body, have provided this helpful list of filtration methods that eliminate pharmaceuticals. Of these, two methods include reverse osmosis (RO) and nanofiltration(NF). As for the NF membranes, the level of pharmaceutical removal varied from moderate to high.
RO membranes, due to their dense and non-porous structure, can effectively isolate a large number of organic macromolecules. In fact, they have achieved >99% rejection rates for all pharmaceutical active compounds, indicating near complete removal. This high level of effectiveness should reassure you about the capabilities of reverse osmosis in removing pharmaceuticals from water.
This is mainly because of the extremely small pore size of the semipermeable RO membrane (0.0001 microns). Thus, RO membranes reveal the highest degree of removal (predominantly 90–95% out of the synthetic water).
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Common pharmaceuticals removed by RO
Reverse osmosis has wide applicability in removing various types of pharmaceutical residues, including:
Antibiotic residues(sulfamethoxazole, trimethoprim, ciprofloxacin, dexamethasone and febantel)
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Antihypertensive agents
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Growth hormones
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Steroids
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Antihistamines
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Lipid regulators
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Pesticides
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Antidepressants
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Painkillers
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Sedatives
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Anti-steroidal anti-inflammatory drugs
Now you are much familiar with how does reverse osmosis remove drugs from water. But is the reverse osmosis technology alone enough for effective removal? Just keep reading!
Enhance RO Systems for Better Pharmaceutical Removal
Active pharmaceutical compounds have been observed in drinking supplies more than ever before and in higher concentrations. Therefore, RO systems combined with other technologies can better prevent most pharmaceutical molecules from passing through.
Combining RO With Other Technologies
Along with reverse osmosis, activated carbon filters and UV features yield higher removal efficiencies. Treatment processes such as advanced oxidation processes (AOPs), ozone oxidation, and powdered activated carbon (PAC) partially remove pharmaceuticals. They are commonly used for water reuse purposes.

If you are looking for an RO system with UV technology, look no further than SimPure RO systems. Our SimPure Y7P series, Y9T, Y10C, and T1-400 series provide an additional level of UV purification and activated carbon filters to remove 99% of impurities.
Tips For Optimizing RO System Performance
If you find your RO system dispensing less quality water, it’s time for system maintenance. Here are a few maintenance tips:
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Thoroughly sanitize the RO components, including storage tanks, faucets, tubing, etc., twice a year.
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Replace the old filters and membranes and install new ones once a year.
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Check for leaks or damage.
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Ensure adequate air pressure.
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Regularly drain the storage tank to prevent bacterial growth
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Periodic water quality testing to ensure the right levels of pH.
Conclusion
Long-time consumption of pharmaceuticals passing through the digestive system to the toilet bowl and reaching your home taps can pose health risks. To avoid pharmaceutical residues, the reverse osmosis water purification technique, aimed at filtering 0.0001 microns size particles, is the best present method. The more pressure, the more efficiently it will separate impurities, including drug traces. Replace your existing water filter with a SimPure UV water filter system and enjoy the improved taste of the filtered water. Drink water that is as clean and pure as it has never been before!
Get SimPure RO+UV Systems for Pharmaceuticals Removal!