Chlordane in Water

🀝 Our content is written by humans, not AI robots. Learn More

Chlordane is a man-made chemical insecticide that was used as a pesticide. It’s insoluble in water and is now banned in the US.

Below, we’ve shared everything you need to know about chlordane in water, including what it is, how it affects your health, and more.

πŸ“Œ Key Takeaways:

  • Chlordane is a pesticide that was used in the past on crops and in home gardening products.
  • This drinking water contaminant was banned in the US in the 1980s, but it’s still manufactured in the country to be used in other parts of the world.
  • Chlordane has several potential health effects, including reproductive damage, developmental delays, and liver effects.

❔ What Is Chlordane In Water?

Chlordane, also known as chlordan, is an insecticide that was used between the late 1940s to the late 1980s for agricultural and domestic uses for seed and soil treatment and termite control.

The chemical was banned for most uses in 1983 by the US Environmental Protection Agency due to its potential to harm the environment and human health. For a time, its only legal use in America was for termite control, until all uses of the chemical were banned in 1988.

Although chlordane is no longer in use, the issue is that this insecticide breaks down slowly in the environment and can stay in the soil for decades.

In water, chlordane is largely insoluble and sticks to the sediment and soil particles found naturally in the water source.

Thankfully, because chlordane hasn’t been used in the US since the 1980s, our risk of exposure to this chemical is now much lower than it used to be. However, if you live near land that was treated with chlordane, you might still be at risk of inhaling chlordane or drinking water contaminated with this pesticide.

1 gallon chlordane insecticide

🚰 How Does Chlordane Get Into Water?

There are two main ways that chlordane can enter a drinking water supply:

  1. Through runoff from a treated area
  2. As a result of improper waste disposal

Runoff is the most likely cause of chlordane water contamination. Because chlordane lingers for so long in soils, it still poses a threat in areas that were treated with the chemical decades ago.

Rain, snow, and flood water carry chlordane in soils and sediments into streams and rivers, which transport the chemical into water bodies that are used as drinking water supplies. Water treatment plants don’t have the facilities to eliminate chlordane, which is why it’s occasionally found in treated water supplies today.

Because it sticks so strongly to soils, chlordane is unlikely to contaminate groundwater – although groundwater contamination isn’t impossible.

πŸ”Ž How To Know If Your Water Contains Chlordane

Chlordane doesn’t have a color in water, and it’s either odorless or has a smell that’s described as “mild” and “irritating”.

That isn’t enough physical evidence for you to accurately detect chlordane by taste or smell alone. Instead, we recommend using one of the following methods to determine your likelihood of drinking chlordane in your water:

Check Your Water Quality Report

If your water comes from a municipal supplier, check your most recent Consumer Confidence Report (or Water Quality Report) to see if chlordane has been listed as a detected contaminant.

Your local water utility should produce an annual Water Quality Report that displays all the contaminants detected in your drinking water in the utility’s testing.

If chlordane has been detected, the utility should note the range detected, and the average concentration present in the treated water supply.

You can ask your water utility for a copy of your Consumer Confidence Report, or check for the report on your water utility’s website.

2021 Denver water quality report
source: Denver Water’s 2021 Water Quality Report

Test Your Water

Another option is to test your water for chlordane.

This is the best option if you use a private water supply and you have reason to believe that it might be contaminated with chlordane, or if you want to confirm your water utility’s test results.

You can buy general pesticide tests that detect a range of chemicals, including chlordane. You might also find a laboratory that tests specifically for chlordane.

We’ve shared more on the testing method for chlordane later in this guide.

🚱 Is Chlordane In Drinking Water Dangerous?

Chlordane is considered a dangerous drinking water contaminant, and numerous studies have linked human exposure to this chemical to a range of serious health effects.

According to the CDC, some of the symptoms and health effects of exposure to chlordane in drinking water are:

  • Headaches
  • Confusion
  • Dizziness
  • Irritability
  • Liver damage
  • Nervous system effects
  • Behavioral effects
  • Changes in blood cells
  • Birth defects

Chlordane is also considered a probable human carcinogen and has been linked to liver cancer and other cancers when high concentrations are ingested over long periods.

Additionally, it’s thought that chlordane affects our ability to have children, although studies on the chemical’s potential reproductive effects are limited.

Nausea after drinking water

πŸ“‰ Is Chlordane In Tap Water Regulated?

Chlordane is regulated by the US Environmental Protection Agency, which oversees water utilities in the country and ensures they’re providing drinking water that’s safe for human consumption.

The EPA Maximum Contaminant Level (MCL) for chlordane is 2 PPB (parts per billion). The EPA also has a Maximum Contaminant Level Goal (MCLG) for chlordane of 0.

What’s the difference between the MCL and the MCLG?

The MCL is the concentration of chlordane that water utilities are legally required to sustain in their water supplies. So, a water utility must reduce its chlordane levels it 2 PPB or below according to EPA regulations.

The MCLG is the maximum level of a contaminant that can be present in a water supply before potential adverse health effects may occur. That means that even legal levels of chlordane in water (up to 2 PPB) might have potential health effects. However, the MCL reflects what the EPA believes water utilities can reasonably achieve with their water treatment processes.

Organizations like the Environmental Working Group (EWG) have set their own more stringent regulations for chlordane in tap water. The EWG’s Health Guideline for chlordane is 0.3 PPB (parts per billion). This Guideline was defined as a public health goal by the California Office of Environmental Health Hazard Assessment, but it isn’t legally enforceable.

Water test

πŸ§ͺ How To Test For Chlordane In Tap Water

You’ll struggle to find a DIY test kit for chlordane that you can use to get an instant reading of your water’s chlordane levels.

Instead, you’ll need to look at laboratory tests, which are fairly expensive and take 1-2 weeks to generate results.

We recommend paying for a chlordane lab test for your water only if you have a specific reason to be concerned about this contaminant in your local area.

To test your water for chlordane with a laboratory test, follow these steps:

  1. Order your test online and wait for it to arrive at your home.
  2. Follow the test instructions to take one or several water samples.
  3. Ship the samples back to the lab and wait for the results (usually within 7-10 days).
Water testing with tap score

πŸ‘©πŸ½β€βš•οΈ What To Do If You’re Concerned About Chlordane In Your Water

If you’re concerned that you might be exposed to chlordane in your drinking water, follow these steps:

  • First, check the EWG tap water database for chlordane to see if your state has reported chlordane in its drinking water.
  • Your municipal supplier should reduce chlordane to below the EPA legal limit of 2 PPB. If they have, but you don’t want to drink even low levels of chlordane in your water, you’ll need to look into installing a suitable filtration system at home.
  • If you get your water from a private source, like an underground well, you’re responsible for your own water testing and treatment. Speak to your local authority if you want to learn more about the chlordane risk in your local area.
  • If you think you’ve been exposed to chlordane in any way, contact your doctor for a checkup as soon as possible.
RKIN U1 countertop RO dispensing cool water

⚠️ Other Ways You Might Be Exposed To Chlordane

Because chlordane is no longer used, our potential for chlordane exposure (aside from in our drinking water) is much lower.

However, we may still be exposed to chlordane in the following ways:

  • From inhaling indoor air. If your home is on a site that was treated with chlordane, especially if it was once treated for termites with this chemical, you might have high indoor chlordane levels in the air even years after the treatment.
  • From eating chlordane-contaminated foods. Even now, chlordane is still in our food supplies due to its persistence in the environment. Foods grown or reared in soils contaminated with this chemical may contain trace amounts of chlordane.
  • From digging in contaminated soils. Digging in soils that were treated with chlordane, or soils around homes that have a history of chlordane termite treatment, may increase your risk of dermal (skin) exposure to the chemical.

πŸ“‘ Final Word: Removing Chlordane From Water

Long-term exposure to chlordane has several concerning health risks, including nervous system effects and liver damage. It’s also possibly carcinogenic.

If chlordane is detected in your water source, we recommend removing it with one of the capable water treatment methods.

πŸ‘¨β€πŸ”§ The best water filter for removing chlordane is the granular activated carbon filter, which pulls chlordane particles out of water using a process called adsorption.

Look for filters that have third-party testing data that supports their ability to reduce chlordane in drinking water.

  • Jennifer Byrd
    Water Treatment Specialist

    For 20+ years, Jennifer has championed clean water. From navigating operations to leading sales, she's tackled diverse industry challenges. Now, at Redbird Water, she crafts personalized solutions for homes, businesses, and factories. A past Chamber President and industry advocate, Jennifer leverages her expertise in cutting-edge filtration and custom design to transform water concerns into crystal-clear solutions.

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top