Pharmaceuticals in Drinking Water: A Guide to Understanding What's in Your Glass

Emerging contaminants in the United States water supply — including pharmaceuticals, antibiotics, and hormones — are garnering attention from public health experts and the federal government. Since the discovery was made in 1999, more studies have come out revealing contaminants in groundwater sources that the U.S. uses for drinking water.

But how do these pharmaceuticals end up in our water supply, and what impact might they have on the people, animals, and plants consuming them? This article discusses the answers to these questions and more.

History of Pharmaceutical Drugs in Drinking Water

In 1999, Christian Daughton, an environmental chemist with the Environmental Protection Agency (EPA), and Thomas Ternes, who worked for Germany’s ESWE-Institute for Water Research and Water Technology, published a journal article revealing the presence of pharmaceuticals in the freshwater cycle. Its publication sparked a flurry of attention and investigation that has continued to this day.

Additionally, in a study conducted from 2004 to 2009, the U.S. Geological Survey measured effluent samples from three wastewater treatment plants. Researchers discovered that effluents from the plants that received discharge from pharmaceutical manufacturing facilities contained prescription drug concentrations between 10 to 1,000 times higher than the concentrations in the effluent of a typical plant. The phenomenon exposes people to medicines they don’t need and endangers our ecosystem with chemicals that can have profound environmental impacts, altering how living organisms develop and grow.

Even though it’s been almost 20 years since Daughton and Ternes published their findings, research into this problem is still in its infancy. However, the urgency behind this problem is growing. One primary reason for the developing concern is that populations in North America and Europe are aging, and they are increasingly relying on prescription drugs to address a wide variety of health issues. In other words, more people plus more medication means more reasons to worry.

Some people find it alarming that there are no regulations mandating water treatment facilities to filter pharmaceuticals out of the water supply. The EPA requires water treatment facilities to test for nearly 90 different potential contaminants, but medicines aren’t on this list. While the federal government does not expect treatment facilities to test for pharmaceuticals, and most are not equipped to remove them, water treatment facilities can remove conventional pollutants like biodegradable organic compounds from the water supply.

Types of Pharmaceuticals Found in Water

First of all, let’s define what we mean when we use the word “pharmaceuticals.” This term refers to controlled substances that doctors prescribe to humans to treat a wide range of medical conditions. So far, studies have shown that the drugs most likely to be present in drinking water include:

• Antibiotics
• Mood stabilizers
• Contraceptives and other synthetic hormones
• Blood thinners
• Heart medication
• Painkillers

The USGS study found the following medications in the water, traceable up to 18 miles downstream from wastewater treatment plants:

• Metaxalone, a muscle relaxant
• Oxycodone, an opioid pain reliever
• Methadone, an opioid prescribed for pain relief and drug withdrawal
• Butalbital, a barbiturate
• Phendimetrazine, a stimulant prescribed for obesity
• Carisoprodol, a muscle relaxant

A 2008 study even found antianxiety and anticonvulsant drugs, as well as a beta-blocker, in tap water. Researchers have also found over-the-counter medications, lotions, colognes, perfumes, and sunscreen. 

What Causes Pharmaceuticals in Drinking Water?

Researchers believe the following factors may lead to pharmaceuticals ending up in our drinking water:

Human Waste

While researchers believe the human body metabolizes most of the medications people take, a small percentage of these drugs still end up leaving the human body and finding their way into the water supply. One of the main ways prescription drugs get into the water supply is through human waste. When you take a medication, your body metabolizes it, absorbing the parts it needs and sending the rest out in your urine or feces. Sometimes your body may sweat out the excess instead, which then washes down the drain during a shower or filters out of your clothes when you wash them.

Animal Waste

Agriculture is another major source of pharmaceuticals ending up in our drinking water. Millions of pounds of animal waste generated by large-scale poultry and livestock operations in the U.S. contain hormones and antibiotics. These drugs are fed to animals to prevent sickness and make them grow faster. As a result, some of these hormones and antibiotics can leach into our groundwater or enter waterways.

Improper Disposal of Medications

Another primary way that pharmaceuticals end up in the water supply is through people flushing their medications. Until recently, experts recommended flushing unused or expired prescriptions down the toilet to dispose of them. When researchers discovered the chemicals from medications were lingering in the water supply, this recommendation changed, and people started finding alternative ways to dispose of their medications, often through medication take-back programs or mixing them with specific materials before throwing them into the trash. However, despite the change in recommendations, many people still believe flushing is the correct way to get rid of medications, so they find their way into the water supply nevertheless.

Landfill Leachate

Pharmaceuticals in the water supply can also come from landfill leachate. A 2015 study by the U.S. Geological Survey examined leachate from 22 landfills in 12 states, and every leachate sample contained contaminants of emerging concern. The study found 43 prescription pharmaceuticals in the leachate overall. For instance, about 91% of tested leachate samples contained the local anesthetic lidocaine. About 82% had carisoprodol, a muscle relaxant, and 77% contained carbamazepine, an anticonvulsant.

The study also found concentrations as high as 3,800 parts per billion in wastewater treatment effluent near pharmaceutical manufacturing plants and other localized areas of elevated concentration are highly likely. Primary factors in variation are likely to include the pharmaceuticals prescribed or manufactured in the area and the size of the population that uses them.

Environmental Impacts of Drugs in Our Water

Research into how pharmaceuticals in water can impact the environment is still in its infancy — not because it isn't essential, but, as mentioned earlier, the scientific community only began to take this issue seriously in the late ’90s. However, we know we aren’t overestimating this problem's potential.

When scientists find a medication in the water supply, it doesn’t stay there. If it’s in the water supply, it can impact what’s in the soil, the air, and the sediment around the area it flows through. It can also impact wildlife in a particular area. The following are examples of environmental impacts drugs in our water can have:

• Deformities and reduced reproduction: A study focused on zebrafish found that even low traces of drugs may affect them. Scientists recreated conditions in a lab environment to expose them to specific pharmaceutical toxins. The result was a decrease in reproductionand an increase in deformities and developmental problems in their embryos.
• Impact on fertility and development: The ongoing exposure of organisms to these pharmaceuticals is affecting ecosystems. Studies have shown that antibiotics directly impact algae and soil microbes. The steroids found in contraceptives can affect the fertility and development of fish, reptiles, and various invertebrates.

There isn’t a one-size-fits-all solution to this problem. Even though initial studies have shown that pharmaceuticals are present in relatively small percentages, there isn't enough available data to determine the impact these trace amounts have on the environment. The scientific community is working to expand its body of knowledge to better protect the world we live in.

Human Health Implications of Pharmaceuticals in Drinking Water

When it comes to pharmaceutical pollution in the water supply and its impact on human health, there’s good news and bad news.

The good news is that these chemicals are not present in our water supply in large amounts. So far, there has not been any scientific proof that these chemicals dramatically affect human health drastically. However, the bad news is long-term exposure is currently unknown but concerning:

• Compounded amounts of pharmaceuticals: Part of the issue with our exposure to pharmaceutical drugs in drinking water lies in how prolonged and compounded it can become. One glass of water could contain several types of pharmaceutical residues that combine synergistically to create more potent hazards or limit our ability to connect a specific contaminant to a particular adverse health effect.
• Chronic exposure: People also ingest pharmaceuticals in drinking water for years. Even though the individual amounts may be minute, they accumulate significantly over the decades. Chronic exposure over an entire lifespan could mean a person ingests hazardous levels of pharmaceuticals, even if every glass of water seems safe on its own. There may also be the potential for people to build up a resistance to certain drugs from extended exposure, which raises concerns.
• Risks for vulnerable segments of the population: While we've currently only found trace amounts of drugs in our water, these pharmaceuticals are intended for specific uses and can have side effects. While one drug might help one person, it could be detrimental to the health of another. There is a particular concern for the more vulnerable segments of the population, especially pregnant women, older adults, and children. Children are especially at risk because their bodies cannot filter toxins the way an adult body can.
• Allergies and side effects: Another concern is that people may be allergic to certain drugs in our water. Antibiotics, for example, are known to cause allergic reactions in susceptible people. Reactions can be mild or severe, with symptoms ranging from hives and wheezing to potentially life-threatening effects.

Because there's no federal requirement for water treatment facilities to test for or filter out pharmaceuticals, there is no way to tell conclusively what people are ingesting over time. Knowing the side effects the pharmaceuticals in question can have on the human body when ingested in other ways, there is a high probability that they are impacting people to some degree.

Challenges in Detecting and Treating Drugs in Water

Identifying and treating pharmaceuticals in the water supply isn’t as cut-and-dried as it sounds. While some strides are being made toward detecting specific drugs in water, water treatment facilities and the scientific community still face the following challenges:

Surrounding Environmental Conditions

Because pharmaceuticals are chemicals, the surrounding conditions can affect them. Final effects can depend on what other biological organisms are in the water or the soil, how hot or cold it is outside, or how much oxygen is available. All these factors can alter one single chemical's impact on the organisms it contacts.

Continually Changing Chemical Profile

Water treatment facilities face a challenge in each chemical's changing nature. For example, in one year, there can be a significant spike in the concentration of one specific pharmaceutical compound, so the treatment is tailored accordingly. However, the next year rolls around, and there is an uptick in a different chemical. This continually changing chemical profile can be challenging for a water treatment facility because it requires continuous adaptation to the treatment plan.

Recreating the Natural Environment for Studies

While there is a reason to believe the presence of pharmaceuticals adversely affects the environment, scientists face challenges — particularly in being able to recreate the natural environment in their labs and studying these things over time rather than drawing conclusions from short-term observations. So, researching more than the presence of one specific compound will be vital to understanding how pharmaceuticals interact with other chemicals to produce effects — whether good or bad — in the environment.

How Can I Protect My Family?

While you shouldn’t panic over this, there are undoubtedly unwelcome elements in your tap water. What steps can you take to protect yourself and your family from drugs in drinking water and their potentially harmful effects?

1. Don't Flush Pharmaceuticals

Part of correcting a problem is committing to being part of the solution. Start by changing some of your habits when it comes to the drugs you take. Ensure you understand how to properly dispose of your medications. Do not flush them down the toilet or wash them down the drain. Also, take steps to minimize pharmaceutical waste. Don’t buy more medicine than you can use before it expires. Ask your doctor for samples if you’re trying a new medication rather than filling a whole prescription you may not use.

2. Invest in a Water Filtration System

Your family deserves water that is clean, healthy, and tastes great. You can enjoy all these benefits when you invest in a water filtration system designed to filter out contaminants that reside in your drinking water. By purchasing a Multipure Drinking Water System, you can reduce the chlorine, Forever Chemicals, lead, microplastics and other contaminants that can be found in your home’s drinking water.

Designed to fit either on your kitchen countertop or below the sink — eliminating bulky bottles or pitchers — the Multipure Drinking Water System takes out the stuff you don’t want and leaves behind clean, great-tasting water for drinking, cooking and washing your fruits and vegetables. Multipure also offers Bath and Garden Products — filters for bathtubs and showerheads, plus options for your whole house and yard.

Sometimes, people assume water doesn’t have to be as clean if they're not planning to drink it, but this assumption couldn’t be further from the truth. Exposure to water and the contaminants in it comes from simple tasks like showering or washing your hands. Chlorine in tap water can have a drying effect on your skin. And, when you use tap water to keep your lawn green or your roses in bloom, you’re putting those contaminants back into the ground around your home.

3. Stay Informed and Advocate for Change

Another way to help your family and society is to educate yourself about local water quality reports and advocate for stronger regulations on medication disposal and water treatment.

Many local health departments test water for contaminants and may have programs for homeowners who want to test their well water. The EPA also requires all community water systems to send out an annual water quality report — Consumer Confidence Report — so you are informed on the quality of your water.

You can also join community efforts to raise awareness about this issue, such as attending town hall meetings or supporting organizations focused on clean water initiatives. Collective action can lead to policy changes that improve water safety and protect public health from pharmaceutical contamination.

What's Next?

While our understanding of pharmaceuticals' impact on our water supply is still somewhat lacking, scientists generally agree that any level of exposure — no matter how small — is potentially harmful. And, while they are still working toward researching the specific effects associated with this dilemma, there’s no question you should take whatever steps you can to reduce your exposure to any unnecessary chemical or substance.

That’s where Multipure comes in. Thanks to our extensive selection of water filtration systems, our customers have discovered firsthand the benefits of having clean, filtered water in their homes — for drinking, washing, and even gardening. Water filtered through our solid carbon block filters isn't merely cleaner, but it looks and tastes better, too.

Don’t wait to make the change to cleaner water. Contact Multipure today and let one of our representatives help you decide which of our filtering options is best for your home.