Nearly a decade ago, thousands of Flint, Michigan residents were exposed to high levels of lead in their drinking water. But it wasn’t until children got sick that they knew something was wrong.
Of the many contaminants in their water supply, it wasn’t the one they could see and taste that was harmful. It was lead — a colorless, odorless neurotoxin.
How does lead get into the public drinking water supplies, and are you at risk? Does reverse osmosis remove lead from water, or do you need a special filtration system? Let’s take a closer look at this devastating contaminant and how to reduce your lead exposure.
Key Takeaways:
- Yes, reverse osmosis is a process that can remove lead from water.
- It works by pushing water through a semi-permeable membrane, trapping the lead particles on one side of the membrane while allowing clean water to pass through it.
- Reverse osmosis systems can reduce the amount of lead in your drinking water by up to 99%, so you can feel confident that the water you and your family are consuming is safe.
How Does Lead Get into Drinking Water?
Lead is an element in the Earth’s crust. Abundant in the environment, it was once a miracle metal popular for use in plumbing. Tough but malleable, it was used in underground water lines throughout the country.
As pipes corrode, the lead inside seeps into the water on its way to your home. Lead pipes and plumbing fixtures are also common in homes built before 1986. A fraction of lead contamination comes from industrial waste, but the majority comes from lead pipes. More than a million American homes are affected.
Further reading: Signs of lead in your drinking water
The Dangers of Lead Poisoning
Lead contamination is a serious health threat for all age groups, but it’s particularly dangerous for children and pregnant women because their bodies absorb lead better.
The health effects of lead poisoning include:
- Muscle weakness
- Fatigue
- Headaches
- Abdominal pain
- Seizures
- Developmental delays
- Behavioral problems
- Learning disabilities
- Infertility and miscarriage
Undetected, the effects of lead in water are cumulative and can cause coma or death.
While the Environmental Protection Agency and the Centers for Disease Control and Prevention acknowledge that no amount of lead in drinking water is safe for children, the legal limit is set at 0.05 parts per million because it’s manageable for public water systems. If you want lead-free water, additional filtration is up to you.
What Is Reverse Osmosis Filtration?
Osmosis is the movement of substances across a semi-permeable membrane from areas of high concentration to low concentration.
Reverse osmosis is the opposite. Reverse osmosis filters use pressure to push water through an RO membrane with microscopic pores, forcing contaminants larger than water molecules to remain on one side. Clean drinking water is collected in a storage tank, and the contaminants go down the drain.
How Is Pressure Applied to the Reverse Osmosis Membrane?
If you drink city water, the incoming household water pressure is usually high enough to do the trick. But if you have a low-pressure well, you need an RO treatment system with an electric or permeate pump.
Does a Reverse Osmosis System Remove Lead from Drinking Water?
Reverse osmosis water filters are extremely effective at removing lead from water. Combined with a carbon prefilter, they can reduce lead levels up to 99 percent.
What Other Contaminants Does a Reverse Osmosis Filter Remove?
Reverse osmosis membranes are vulnerable to chlorine, and they can’t remove most chemicals. But reverse osmosis filtration systems are equipped with carbon filters.
Together, they’re the dynamic duo of water filtration. They remove lead plus:
- Chlorine
- Chloramines
- Pesticides
- Herbicides
- Volatile organic compounds
- Heavy metals
- Drug residue
- Microplastics
- Emerging contaminants and other impurities
Reverse osmosis systems are also effective for removing bacteria larger than the membrane’s pore size — typically 0.001-.0001 microns.
Reverse Osmosis Versus Whole-House Water Treatment Systems for Lead
Whole-home filters are plumbed into your water supply line in the basement or garage. They provide an endless supply of water on demand, but they can’t remove lead from pipes and plumbing fixtures inside your home.
The RO process is slow and can rarely keep pace with house-wide water demand, so most RO filters are installed on the countertop or under the kitchen sink and provide water only for drinking and cooking.
But since most lead exposure occurs from consuming contaminated tap water; RO filters are ideal because they remove lead from interior pipes. Human skin absorbs little lead, but you can add a KDF shower head filter to purify your bathing water.
Reverse Osmosis Systems — Pros and Cons
RO systems win the blue ribbon for filtration capability, but like other drinking water filters, they have pros and cons. Let’s compare their advantages and disadvantages.
Advantages — Comprehensive Filtration
There’s no better water treatment system for removing harmful contaminants than a reverse osmosis unit. If safe drinking water is your goal, an RO filter is the solution.
Compact Size
Compared to a whole-home water filter, an RO unit takes very little space.
Easy Installation
Unlike whole-house water systems, reverse osmosis units require no permanent changes to your plumbing. They can be installed in under an hour with no special tools.
Portability
RO systems are apartment-friendly and portable. Perfect for nomads, they disconnect easily and can travel with you.
Disadvantages — Limited Capacity
Whole-home filters provide clean water on demand throughout your home. RO systems have a maximum capacity of 10-75 gallons per day.
They’re Cold Water Only
Hot water can damage the RO membrane, so reverse osmosis systems have dedicated dispensing faucets for drinking water. Warm water is still accessible for washing your hands through your regular faucet.
Water and Energy Use
For every gallon of pure water an RO filter produces, it creates up to two gallons of waste water, adding to your utility bill. In drought-prone areas, water pressure may not be sufficient for systems to work without a pump, so you’ll pay more for electricity, too.
Taste
RO filters remove lead, but they also strip water of the healthy minerals that give it its characteristic flavor. Some say it’s great-tasting water comparable to bottled, but others disagree. Most people say that reverse osmosis water tastes flat at first but that they get used to it after a few weeks.
Cost
An RO system costs less than a whole-house filter but significantly more than a carbon filter alone. Still, a reverse osmosis system is your best bet for removing lead contamination.
Testing Your Water for Lead
Doing a test is the only reliable way to detect excessive levels of lead in water. Municipalities do a good job of monitoring water quality, but tap testing is limited to a handful of homes per year.
Doing a water test is simple. Communities with underground lead pipes may offer them free for residents. Otherwise, we recommend purchasing a home test kit online.
Test strips cost as little as $10-$20, but we suggest SimpleLab’s Tap Score because it’s affordable, easy and accurate. And if there’s lead in your water, results include product recommendations. If you’ve never purchased a filtration system before, it’s time-consuming, so the advice is a plus. SimpleLab doesn’t sell water filters —they work only for you.
Other Ways to Reduce Lead Exposure
A water filter is the best long-term solution for lead. But if testing shows high levels, you need to take immediate action by:
- Switching to bottled or distilled water.
- Using only cold water. Warm water coaxes lead from pipes.
- Clean faucet aerators weekly to remove solid pieces of lead.
- Letting water run for two full minutes before drinking it to flush out loose particles.
Boiling water does not remove lead because its boiling point is higher than water.
Final Thoughts
Until lead pipes are a thing of the past, lead in water remains a serious health issue. So, why take chances when an RO system will not only remove lead but will also improve your overall water quality? Clean water is essential for your health, and with the right filtration system, it’s just a step away.