What are Volatile Organic Compounds (VOCs) in Water?

Volatile organic compounds, or VOCs for short, are a common type of EPA-regulated drinking water contaminant.

It’s important to be aware of the risks of volatile organic compounds (VOCs), particularly as they’re so widely used, making them a highly likely environmental pollutant.

In this guide, we’ve shared all you should know about VOCs, including what they are, how you can test for them, and how to eliminate them from your water supply.

🔎 What Are VOCs (Volatile Organic Compounds)?

Volatile organic compounds are organic chemicals that are released by a broad range of industrial, agricultural, and household products, including paint thinners, solvents, fertilizers, and gasoline.

VOCs have very low boiling points, which means that when they’re exposed to “normal” air temperatures, they’re quick to convert to a gas or vapor form.

Even when used in temperatures below freezing, VOCs are capable of converting into a gas, which is why they’re known as “volatile” compounds.

In Water As	Perchloroethylene (PCE), Trihalomethane (THMs), Methyl tert-butyl ether (MTBE)
Sources	Groundwater leaching and disinfection of public water supplies Products used in daily basis (gasoline, glues, paint, cleaning formulas, permanent markers, and more)
Maximum Contaminant Levels (MCLs)	EPA: PCE - 5 ppb THMs - 80 ppb MTBE - 13 ppb EWG: PCE - 0.06 ppb THMs - 0.15 ppb MTBE - 13 ppb
Potential Health Risks	Carcinogenic effects, dizziness, kidney and liver damage
Treatments	Activated Carbon Filters

☣️ Most Common VOCs in Water

The commonly detected VOCs in public water supplies are:

• PCE (perchloroethylene): A byproduct of industrial solvents, typically used as a degreaser for industrial processes or in dry cleaning applications. You may also find PCE in at-home laundry and dry cleaning products as well as shoe polish and certain solvents.
• Trihalomethane: A water disinfection byproduct produced when water is disinfected with chlorine or chloramine. Chlorine merges with organic material naturally present in the water, producing byproducts including trihalomethane. This is a big issue for people who drink from city water supplies. If you disinfect private wells with chlorine, you’ll likely face the same problem.
• Methyl tert-butyl ether (MTBE): This VOC is used as a lead substitute to improve the octane reading of gasoline. The main causes of MTBE water contamination are spillages and leaking underground storage tanks.

📥 Where Do Volatile Organic Compounds Come From?

VOCs are present in thousands of products that are used on a daily basis. These include gasoline, glues, printer inks, cleaning formulas, varnishes, fuels, paints, permanent markers, and much more.

If you’re familiar with the distinct whiff you get at the gasoline station or when you remove the lid off a permanent marker, you’ll already be familiar with the smell of VOCs being released from a product. Once a VOC is exposed to air, it takes on a gaseous form immediately.

VOCs don’t just pose an environmental hazard in the air, though – these chemical pollutants are also detected in groundwater and public water supplies.

🚱 How Do VOCs Get Into Water?

VOCs are usually a byproduct of human activity. Some of the most common activities that result in VOC contamination in surface water and groundwater are:

• Improper VOC disposal, leading to groundwater leaching.
• Chlorine disinfection, resulting in chemical reactions that release VOCs as a byproduct.
• Pollution, caused by fuel spillages on the ground or leakage from a storage tank underground resulting in groundwater contamination.

Once VOCs get into a water supply, natural environmental occurrences such as precipitation cause these organic chemicals to merge into rivers, streams, and aquifers in private wells, affecting water quality.

Some VOCs, such as those released from plants, are naturally occurring, but they’re much more commonly found as a direct result of human behavior or a human-related mistake.

⚠️ Are VOCs Dangerous?

Some VOCs are dangerous, while some have few known health effects, and others haven’t been studied enough, so we’re not aware of whether they’re dangerous or not.

Sources like the EPA say that VOCs may have dangerous effects including eye, nose and throat irritation, kidney, liver, and nervous system damage, headaches, nausea, and cancer.

🩺 Health Risks Associated With VOCs

A Total Exposure Assessment Methodology report by the EPA found that around 12 common VOCs were found in concentrations up to 9 or 10 times higher indoors than outdoors.

When the problem is, quite literally, so close to home, it’s easy to see how volatile organic compounds may pose so many human health effects.

Some of the most common potential health effects associated with prolonged exposure to VOCs include:

Carcinogenic effects

According to the Environmental Working Group, there are currently 12 detected VOCs that are classed as “potentially carcinogenic” (cancer-causing) – with 9 of these being classified by the EPA:

• Vinyl chloride
• Benzene (from gasoline)
• Styrene
• 1,2,3-Trichloropropane
• 1,1,2-Trichloroethane
• Tetrachloroethylene (both PCE and PERC)
• Trichloroethylene (TCE)
• 1,4-Dioxane
• 1,2-Dichloroethane
• Carbon tetrachloride
• 1,2-Dichloropropane
• Dichloromethane (methylene chloride)

Not included in this list, but still important to know about, is MTBE, which has been proven in animal studies to cause kidney and liver tumors.

Neurological Effects

Studies have found that exposure to MTBE in the air or drinking water may have damaging neurological effects, from headaches and nausea to dizziness and even depression.

Health Risk To Organs

VOCs can also pose a health risk to a number of organs in the human body, including the kidneys and liver. Additionally, certain VOCs have shown the potential to cause nerve damage.

🧪 How to Test for VOCs in Water

VOCs, once waterborne, can affect your water quality without affecting its taste at all. While you can smell airborne VOCs, in liquid form, they present no smell or taste.

Testing your water is the only way to detect volatile organic compound contamination.

Look for state-certified laboratories in your area that can test water for VOCs like PCE, Trihalomethane, and MTBE.

The process of getting your water tested is:

1. Order a lab test kit online and wait for it to arrive.
2. Take a sample of your drinking water supply and send it to the laboratory.
3. Wait for the lab to perform testing.
4. Receive your results to determine the quantity of VOCs in your water, and whether this quantity exceeds the maximum levels set by the EPA.

Laboratory water testing for VOCs commonly costs around $100 to $200.

📉 Are VOCs In Water Regulated?

The EPA currently regulates 23 VOCs in public drinking water systems, so if you use city water, you know that legally, your local authority must reduce VOCs to below the Maximum Contaminant Level set by the EPA.

However, not all VOCs are regulated, so some drinking water supplies may contain unsafe levels of unregulated chemicals.

If you own a private well, your water supply isn’t regulated. It’s your job to test for VOCs and employ suitable water treatment for VOC reduction to make your well water safe for drinking.

✅ How to Remove VOCs from Drinking Water

Here are some of the best methods of VOCs removal from drinking water.

Best Option: Activated Carbon Filters

Activated carbon filters are the most effective solution for removing VOCs, including benzene and PCE, from drinking water. These filters use a process called adsorption to pull chemical contaminants out of a water supply.

There are lots of different carbon filters for various use points, from the smaller refrigerator or pitcher filter, to the multi-stage whole house carbon filter unit. There’s a carbon filter for every requirement and every budget.

Carbon filtration systems also remove chlorine, so they’re a great choice for treating chlorinated drinking water supplies.

Some carbon filter media are designed to handle a greater quantity of VOCs than others. Look for a filter that’s certified for VOCs reduction or removal if you want to be certain that it performs as advertised.

📑 Final Word

VOCs contaminate drinking water supplies across the US. Thankfully, removing these dangerous chemicals from our drinking water is possible with a simple, affordable water treatment process: activated carbon filtration.

If you’re new to water filtration and want a good place to start, we recommend water filter pitchers for VOCs removal. Most pitcher filters are made from carbon-based media and can remove more than 90% of VOCs, making them an affordable, effective solution for at-home use.

The Clearly Filtered Water Pitcher is the best pitcher filter you can buy today, removing up to 99% of 91 different VOCs.

❔ FAQ

What Is Vinyl Chloride?

Vinyl chloride is a colorless, flammable VOC used to produce PVC. It’s commercially manufactured and a Class 1 carcinogen, meaning that it has a high cancer-causing potential. You can remove vinyl chloride from water with activated carbon filters.

Does Reverse Osmosis Remove VOCs?

Reverse osmosis systems can remove a whole host of EPA-regulated contaminants, including lead, fluoride, chromium, and bacteria. But the reverse osmosis membrane separation process itself doesn’t remove VOCs. If the RO filter comes with a carbon pre-filter or carbon post-filter, it should be able to filter VOCs.

Does Boiling Water Remove VOCs?

No. Boiling drinking water will increase the concentrations of VOC as the heat will evaporate some of the water. You’d need your own DIY distillation setup to catch the evaporated water particles and send them into a clean chamber – a process that takes several hours.