How Does a Lead Water Filter Work?

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The water crisis in Flint, Michigan shows how water contamination can deteriorate our health and even cause death in some cases.

Thousands of Flint citizens were exposed to lead in their drinking water, killing 12 people and making dozens sick.

Lead contamination can cause several health issues in adults and children alike. Even worse, young kids can end up with irreversible health problems like brain damage, hampered physical development, low IQ, and more.

Fortunately, lead water filters can eliminate up to 99.9% of the metal, providing healthy, clean drinking water. But how do lead filters work to remove the notorious water contaminant? We’ll uncover it in the guide below.

Key Takeaways

There are different types of lead water filters. These are:

  • Activated carbon filters – Adsorbs lead into its surface pores
  • KDF-55 filters – Causes redox reaction trapping soluble lead
  • Reverse osmosis systems – Lead gets rejected by semipermeable reverse osmosis membrane
  • Water distillers – Water evaporates leaving all lead behind

How Does a Lead Water Filter Work?

Using a lead water filtration system is one of the easiest ways to remove lead from water.

Whole House and Single-Point Lead Filtration Systems

Thereby, you can choose between point-of-use (POU) and point-of-entry (POE) water filters.

A POU lead filter will clean your water at a single point, such as your kitchen sink. This type of filter is mainly used for drinking purposes and comes in form of an under sink or countertop system, a faucet unit, as a pitcher, etc.

POE water filtration systems supply the entire house. As such, they need to be plumbed into the main water line. The benefit: You get lead-free water at every single tap.

Lead Purification Systems

The common water purification systems for lead removal include:

  • Activated carbon filters: These filters use adsorption for optimal removal of lead and few other heavy metals. Carbon filters also remove chemicals and improve waste taste. Nonetheless, not all activated carbon filters work effectively when it comes to lead reduction. Even more, a few lose their removal capacities pretty fast.
  • Reverse osmosis systems: Using an RO system is one of the best ways to eliminate lead from your home water supply. A good semipermeable reverse osmosis membrane rejects more than 99% of the heavy metal.
  • Distillation: Though not a water filter per se, a water distiller is the most effective and safest device to eliminate all lead from water.
  • KDF-55 filtration: KDF-55 converts soluble lead into an insoluble form, which is then electroplated onto the filter media.

Different Water Filter Cartridges and Membranes

How to Make Sure Your Water Filter Really Removes Lead

Lead contamination is not something to be brushed off the shoulder. Many water filters work great for optimal lead removal, but many don’t.

Generally, a lead water filter must have an ANSI/NSF certification, particularly for lead reduction. So when purchasing a product, look for ANSI/NSF standard 53 certifications or testing. Furthermore, check the product manual for lead reduction rates.

NSF International is an independent, non-profit organization that sets industry standards. Third-party firms like the CSA (Canadian Standards Association) or the WQA (Water Quality Association) certify particular products based on these industry standards.

For a lead water filter to achieve certification from either agency, it must reduce lead levels below the EPA’s action level of 15 parts per billion. 15 ppb isn’t perfect, but it’s a good start.

On a side note, some RO systems are certified against NSF standard 58 for lead removal. Both standards are fine.

Using the Right Kind of Water Filter

In all honesty, lead removal isn’t so much about the filter model but the type of filtration method used. As mentioned before, KDF filtration, carbon filtration, reverse osmosis, and distillation are the go-to methods for removing lead from water at home.

You can find them in the form of under-the-sink water filters, whole house filtration systems, countertop units, water filter pitchers, faucet filters, gravity-fed systems, water distillers, several types of RO systems, and more.

As long as there exists an NSF standard 53 certification for lead reduction, you can go for one or another filtration system for your home.

Replacing Old Filter Cartridges

With carbon water filters and reverse osmosis systems in particular, it’s important to replace the filter elements on a regular basis to keep everything functioning optimally. Otherwise, lead reduction capacities will exhaust eventually.

Check Your Lead Levels

You cannot choose an appropriate lead filter system for your home unless you know about lead concentrations in the water. Once you’ve figured that out, you can go shopping accordingly.

Not sure how to check lead levels? No worries! Here are a few tests that indicate the amount of lead in water.

DIY Tests

You can purchase a DIY testing kit for $10-$50. However, note that a few kits only test your water for one or two water analytes, whereas others check several impurities and contaminants, including lead.

Also, some do-it-yourself testing kits only give yes/no results for lead contamination. Simply put, you will know that you have lead in your water, but how much? The test will not specify it.

Water Quality Report from Supplier

You can also find out about lead levels in your water through a consumer confidence report. Since city water suppliers are bound to conduct annual water tests and publish their reports for free, you can access the latest edition and easily check for lead content.

That said, note that these reports do not consider lead that enters your water supply through household plumbing or distribution channels. In other words, you cannot rely on your local water quality report for 100% accuracy.

Laboratory Test

If you’re looking for the most reliable way of determining lead levels in your water, we suggest sending a water sample to a certified laboratory.

A lab professional conducts testing per the industry standards and provides you with the most precise findings.

It’s best to run multiple tests to know the exact lead concentration in your water. Since lead presence is inconsistent, a single test might not give accurate results.

Removing the Lead Source

As an alternative to filtering lead, you can also try to identify and get rid of the lead contamination source.

For instance, your home’s plumbing system can be the culprit. If possible, you should consider renewing it.

If you’re on well water, ask a certified contractor to check the well and the pump – are they contributing to lead in your water supply?

Other Ways to Reduce Lead Exposure

Use Cold Water

Though this isn’t a practical solution, it works for the time being.

Avoid using hot water directly from the tap. Hot water absorbs lead faster than cold water; therefore, it’s best to use cold water instead.

You can always heat up water on the stove or in an electric kettle.

Furthermore, the CDC suggests flushing water before utilizing it for cooking or drinking purposes. So, if you haven’t used water overnight, run it for 1-2 minutes. This will lower lead levels.

We recommend not to waste the water, though. Instead, you can collect it for watering your plants.

Kitchen Faucet

Can Lead in Water Make You Sick?

The Flint crisis has explained enough about the detrimental effects of ingesting lead. So, yes, lead does not only make you sick but can prove to be fatal!

Even in small amounts, lead exposure can cause muscle and joint pain, fatigue, and headaches.

Aside from that, it can cause severe health issues including reduced kidney function, cardiovascular issues, reproductive problems, and high blood pressure.

What’s more, kids may suffer from a rather serious and long-term impact of lead ingestion. It can cause brain damage, reduced appetite, constipation, loss of concentration, poor IQ, vomiting, and inhibited physical development.

Unfortunately, this infamous contaminant can also adversely impact pregnant women. Lead can pass the placental barrier and cause premature birth or miscarriage in a worst-case scenario.

If you have any thoughts about the question, how does a lead water filter work, please don’t hesitate to leave a comment below!

About the Author Gene Fitzgerald

Gene Fitzgerald is one of the founders of BOS and currently head of content creation. She has 8+ years of experience as a water treatment specialist under her belt making her our senior scientist. Outside of BOS, Gene loves reading books on philosophy & social issues, making music, and hiking.
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