2,4-D, short for 2,4-dichlorophenoxyacetic acid, is an organic compound that’s widely used as a herbicide and has been used as a pesticide on turf, lawns, and farmland since the 1940s.
Here, we’ve shared the potential risks of 2,4-dichlorophenoxyacetic acid in drinking water. You’ll also find other important information about this contaminant, including how it contaminates water supplies and how to test for it in your water.
📌 Key Takeaways:
- 2,4-D is a pesticide and herbicide that’s used to control broadleaf weeds on crops, forestry sites, lawns, and turf.
- This organic compound typically enters water supplies as a result of runoff and seepage from contaminated ground.
- 2,4-D is very soluble in water and has several known health risks.
Table of Contents
- ❔ What Is 2,4-D In Water?
- 🚰 How Does 2,4-D Get Into Water?
- 🔎 How To Know If Your Water Contains 2,4-Dichlorophenoxyacetic Acid
- 🚱 Is 2,4-D In Drinking Water Dangerous?
- 📉 Is 2,4-D In Tap Water Regulated?
- 🧪 How To Test For 2,4-D In Tap Water
- 👩🏽⚕️ What To Do If You’re Concerned About 2,4-D In Your Water
- ⚠️ Other Ways You Might Be Exposed To 2,4-D
- 📑 Final Word: Removing 2,4-D From Water
❔ What Is 2,4-D In Water?
2,4-D, or 2,4-dichlorophenoxyacetic acid, is a selective herbicide that’s used to control weeds including dandelion, chickweed, clover, and plantain. It’s used in forestry and on farmland, turf, home lawns, and according to Mark A. Peterson of Dow AgroSciences in an article published by Cambridge University, “Since its discovery and initial commercialization in the 1940s, 2,4-D has been an important tool for weed control in a wide variety of crop and noncrop uses.”
2,4-D is highly soluble in water and has the chemical formula C8H6Cl2O3. It’s made from chloroacetic acid and 2,4-dichlorophenol, and is available in various different forms, including esthers, salts, chemicals, and acid form.
2,4-dichlorophenoxyacetic acid is favored for its ability to kill weeds while having little effect on grassland and most agricultural crops. This widely used herbicide first became available for commercial use in 1945 and is now one of the oldest herbicides in the world.
Despite its known health effects, 2,4-D is still used as an active ingredient in more than 1,500 herbicide products today.
In the US, the EPA has approved the use of Enlist Duo, a herbicide combining 2,4-D and the weed killer Roundup (also known as glyphosate), and the registration of this product was renewed in 2022. In an attempt to protect the environment, the EPA requires the manufacturer to share runoff and spray drift measures on the product label, which all users of the herbicide are required to follow.
You might hear 2,4-D referred to as one of its trade names, including Aqua-Kleen, Lawn-Keep, Plantgard, Salvo, Weedone, and Weedar.
🚰 How Does 2,4-D Get Into Water?
The main causes of 2,4-D contamination in drinking water are runoff and infiltration from turf and farmland treated with this herbicide.
2,4-D may enter an above-ground water source (such as a river and lake) if it’s carried from contaminated land in rainwater, snow, or flooding.
It may also enter groundwater sources (like wells and springs).
Chemical leaks and spills may also cause 2,4-D to enter surface water sources that are used to supply drinking water.
Different forms of 2,4-D have different effects in the environment. The ester forms of this herbicide have the potential to be highly toxic to aquatic life.
How do we end up drinking water that’s contaminated with 2,4-D?
When water is processed at a treatment plant, the filtration methods used often aren’t designed to remove herbicides and similar complex contaminants. So, even if your water is potable and disinfected, it may still contain low levels of 2,4-dichlorophenoxyacetic acid.
Thankfully, 2,4-D has a short half life and a low persistency in water. The chemical degrades rapidly under aerobic conditions, so the risk of high concentrations of 2,4-D in your drinking water is minimal.
🔎 How To Know If Your Water Contains 2,4-Dichlorophenoxyacetic Acid
2,4-dichlorophenoxyacetic acid is said to give water a poor taste and smell, but it’s unlikely that trace levels of this contaminant will be noticeable to most people.
If you want to know for certain whether or not your water contains 2,4-D, use one of the following detection methods.
Check Your Water Quality Report
First, if you have municipal water, check your water utility’s most recent Consumer Confidence Report, also called a Water Quality Report, and see if 2,4-D is listed as a detected contaminant.
Your water utility should routinely test the water supplied for drinking and note their findings in the Consumer Confidence Report. If 2,4-D has been detected, the Report should note the range of concentrations present in the water, and the average concentration from this range.
Check your water company’s website to find your latest Consumer Confidence Report online.
Test Your Water
You might prefer to use your own at-home testing methods for 2,4-D in water, or you might have a private water supply that isn’t treated by a water utility.
In this case, you can learn about your water’s 2,4-D concentration by using a laboratory contaminant test.
2,4-D water tests aren’t super common, and it might be worth contacting your local authority if your region has a known problem with this contaminant. Your local authority can guide you on where to find 2,4-D tests and potentially offer you a free or discounted test.
🚱 Is 2,4-D In Drinking Water Dangerous?
2,4-D in drinking water is considered dangerous because it has several known health effects and is slightly toxic.
According to the International Agency for Research on Cancer, 2,4-D is a possible carcinogen. The chemical has been found to increase the body’s lymphocytes, potentially causing non-hodgkin’s lymphoma. However, the EPA doesn’t classify it as potentially cancerous because of “insufficient evidence in humans and limited evidence in experimental animals”.
If you drink water with high concentrations of 2,4-D, you might experience the following symptoms:
- Aggressive behavior
Some of the known long-term health effects of exposure to 2,4-D in water include:
- Kidney failure
- Birth defects
- Damage to the kidneys and endocrine glands
- Skeletal muscle damage
- Fertility problems
What we know about 2,4-D so far suggests that the chemical doesn’t build up in the body. While it’s thought to be readily absorbed into the bloodstream, 2,4-D should be flushed from the body within around 4 days, primarily in the urine.
📉 Is 2,4-D In Tap Water Regulated?
2,4-D in tap water is regulated by the US Environmental Protection Agency (EPA), which produces Primary Drinking Water Standards for contaminants that might compromise the safety of a drinking water supply.
Under these Standards, the EPA has enforced a Maximum Contaminant Level (MCL) of 0.07 mg/L, or 70 PPB (parts per billion) for 2,4-D in public tap water, meaning that water utilities must reduce their 2,4-D levels to within this concentration.
The Maximum Contaminant Level Goal (MCLG) – the maximum amount of 2,4-D that the EPA believes can be present in water without causing health effects – is also 0.07 mg/L.
Some organizations believe that the EPA legal limitations for 2,4-D are too lenient, given the contaminant’s potential effects in the human body.
For instance, the Environmental Working Group (EWG) has established a non-enforceable Health Guideline of 20 PPB for 2,4-D, based on its own research into the potential health effects of this chemical.
🧪 How To Test For 2,4-D In Tap Water
There are only a few laboratory tests for 2,4-D. You might find tests for pesticides and herbicides that detect 2,4-D amongst other contaminants, or you might find specific tests that solely detect 2,4-D.
To test for 2,4-D with a laboratory test, follow these steps:
- Order your preferred test and wait for it to be shipped to you.
- Take one or several samples of your water, following the test instructions.
- Send your samples to the laboratory for analysis.
- Wait for your results to be emailed to you (usually within 2 weeks).
There’s one specific reason to consider testing your water for 2,4-D: if you have a private drinking water supply and you’re concerned about 2,4-D contamination, especially if you live in a region with known problems with 2,4-D in natural surface waters or groundwaters.
👩🏽⚕️ What To Do If You’re Concerned About 2,4-D In Your Water
If you’re concerned about 2,4-D drinking water contamination, we advise you to do the following:
- Find out whether you’re at risk of drinking 2,4-D in your water. You can learn which states have reported 2,4-D in their public drinking water supplies in this EWG database.
- It’s highly unlikely that you’ll be exposed to high doses of 2,4-D in your water if you’re on a municipal supply. If 2,4-D is detected in your water below the EPA MCL but you don’t want to drink even trace amounts of this chemical, you’ll need to install a water filtration solution to remove 2,4-D at home.
- If you get your water from a private, non-regulated supply, it’s your job to test for certain contaminants and install a water treatment system when necessary. Speak to your local authority to learn more about the contaminants that have been detected in your local groundwater supplies.
- Contact your doctor if you think you’ve been exposed to 2,4-D and you’re concerned about the potential health effects.
⚠️ Other Ways You Might Be Exposed To 2,4-D
There are a few other ways, aside from drinking 2,4-D in your water, that you might be exposed to this herbicide in one of its various chemical forms:
- From eating contaminated foods – Since 2,4-D is used to control weed growth on many types of crops, it’s possible that you might be exposed to this herbicide through eating contaminated foods. 2,4-D is often used on field corn, sugar cane, hazelnuts, soybeans, spring wheat, and barley in the US.
- From incorrectly handling 2,4-D – Certain acid and salt forms of 2,4-D are known to cause severe eye irritation when handled by humans. Incorrect handling of the chemical – such as if you’re using it to treat your lawn – could result in health problems.
- From occupational exposure – If you work in an agricultural role that involves handling 2,4-D, you’re at risk of dermal (skin) exposure or inhaling the chemical.
📑 Final Word: Removing 2,4-D From Water
2,4-D has been linked to several unwanted health problems, including cancer, so we don’t blame you if you wat to remove this contaminant from your drinking water supply.
The most effective way to remove 2,4-D from your water supply is with a granular activated carbon filter.
This filter uses a sponge-like process called adsorption to pull certain contaminants, including pesticides and herbicides, out of the water as it passes through.
👨🔧 Choose a granular activated carbon filter that’s sold by a reputable manufacturer and has test results that showcase its ability to reduce or remove 2,4-D.