Does Your Water Contain an Unsafe Level of Cadmium?

Today, I’ll continue my review of some of the more common drinking water contaminants with a look at Cadmium. I’ll touch on how Cadmium can affect water quality and share information on things you can do to minimize your family’s exposure to the contaminant.

Cadmium, a soft, silver-white metal, is found in the Earth’s crust. It typically gets into our drinking water supply in the following ways: 1) through the erosion of natural deposits, 2) through the corrosion of galvanized pipes, 3) from metal refineries, or 4) from runoff from discarded batteries or paints. Consuming water containing Cadmium at levels equal to or greater than 0.005 mg/L can cause adverse health effects.

Fortunately, Cadmium is one of the drinking water contaminants regulated by the EPA. This means public water companies are required to monitor their water supply for Cadmium and work to ensure the water they provide their customers does not exceed the legal limit for the contaminant. However, even with this standard in place, it’s still possible for your tap water to contain excessive amounts of Cadmium. Using data from the EPA, I estimated as many as 20 thousand Americans were exposed to water with potentially unsafe Cadmium levels at least once from 2015 to 2019.

How Cadmium Can Affect Water Quality and Your Health

Both natural processes (e.g., erosion of naturally occurring deposits in the Earth’s crust) and human activities (e.g., waste disposal) can contaminate our water supply with Cadmium.

What is Cadmium, exactly? Cadmium is a naturally occurring metal used in a variety of consumer products, including batteries and paints.

How can drinking water that contains Cadmium affect your health? If you consume water that contains elevated levels of Cadmium over many years, you may develop kidney damage.

At what level can Cadmium cause health problems? Cadmium is known to cause adverse health effects when its concentration in drinking water is at or above 0.005 mg/L.

In an effort to protect our health, the EPA established legally enforceable standards to limit the amount of Cadmium in our drinking water. Public water companies are required to ensure the concentration of Cadmium in the water they provide their customers is kept at or below 0.005 mg/L.

Given available treatment technology, water utility companies should be able to provide drinking water that meets this quality standard. However, at least one public water system violated the regulatory limit for Cadmium in 2019.

Does Your Drinking Water Contain a Harmful Amount of Cadmium?

Public water companies are required to provide customers with an annual water quality report, also known as a Consumer Confidence Report (CCR). Inside this report, you’ll find important information about your drinking water, including where it comes from, and whether it tested positive for any regulated contaminants like Cadmium.

Most Populated Areas with Violations for Cadmium from 2015 to 2019

Water System
Granbury, TX
Acton MUD
Montgomery, NY
Holiday Mobile Park Inc.
Crown King, AZ
Crown King Water Company
Salinas, CA
Vista Del Toro WS

If you’re curious to know how much Cadmium was found in your city’s drinking water, grab a copy of the latest CCR and look for the section of the report that covers “Inorganic Chemicals.” Here, you’ll find test results for Cadmium as well as other contaminants like Antimony, Arsenic, and Mercury.

How to Interpret Your Water Quality Report

When looking at your water quality report, you’ll see test results for Cadmium reported in Parts per Billion (ppb). 1 mg/L equals 1,000 ppb, so 0.005 mg/L is equivalent to 5 ppb.

Below is an example of what you might see on your annual water quality report if Cadmium is detected in your town’s drinking water:

Example Water Quality Report

MCLG (1)MCL (2)Average
Your Water

Definitions from the EPA:
1. Maximum Contaminant Level Goal (MCLG) – The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety and are non-enforceable public health goals.
2. Maximum Contaminant Level (MCL) – The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to MCLGs as feasible using the best available treatment technology and taking cost into consideration. MCLs are enforceable standards.

In this example, water samples contained an average of 7 ppm of Cadmium, exceeding both the public health goal level (MCLG) and the legal limit (MCL) for the contaminant.

Will You Be Notified If Your Water Contains an Unsafe Level of Cadmium?

In addition to providing you with an annual quality report, your water company is required by the EPA to notify you if they identify a problem with your drinking water.

If your water company delivers water that could negatively impact your health, they have to notify you of the situation within the timeframe set by the EPA. Depending on the severity of the issue, the company is given 24 hours to 30 days to provide this notice.

If your city’s water exceeds the Maximum Contaminant Level (MCL) for Cadmium, your water company must notify you within 30 days of the violation. Typically, you will receive this notice via the media or through the mail.

What Can You Do to Remove Cadmium from Your Tap Water?

Fortunately, if you want to limit your family’s exposure to Cadmium, there are several affordable yet effective options for removing the contaminant from your tap water.

But how can you tell which products work and which ones don’t? Well, if you want peace of mind, I recommend choosing a water treatment product that is certified by NSF International (NSF) to be effective at removing Cadmium from water.

What does the NSF certification represent? When a product is NSF certified to remove Cadmium, you can rest assured that:

  • the manufacturer’s contaminant reduction claims have been verified;
  • the system was tested to confirm it adds nothing harmful to the water;
  • the system has been found to be structurally sound;
  • the product’s advertising, literature, and labeling have all been verified as accurate;
  • and there is testing in place to determine whether the quality of the product is consistent over time.

Do all NSF certified water filters work against Cadmium? Water treatment devices can earn certification for meeting one or more NSF standards or protocols. But only certain NSF certified products, like Reverse Osmosis devices that meet NSF standard NSF/ANSI 58 for Cadmium, are certified to reduce the amount of the Cadmium in your water.

One such product, OptimH2O Reverse Osmosis + Claryum by Aquasana, is NSF certified to remove up to 95.3% of the Cadmium found in your tap water. This device requires installation underneath your sink, so the manufacturer recommends enlisting the help of a professional to make sure it gets done right.

3 steps for selecting the right water treatment system for your family:

  1. Review your area’s annual water quality report to find out what’s in your drinking water.
  2. Determine which contaminants you’d like to reduce from your water.
  3. Select a water treatment product that is NSF certified to work effectively against those contaminants you’d like to reduce from your tap water.

Just remember, no matter which water treatment product you choose, you need to make sure to perform the routine maintenance suggested by the manufacturer. This will help keep the device in proper working order and limit your family’s exposure to Cadmium.



I’ve moved several times over the years, so I know just how stressful it can be to relocate. I want to help put your mind at ease. That’s why I research and write about all the things I think you should consider when moving to a new town.

Recent Content