Lead is one of the most common drinking water contaminants, and it’s also one of the worst – so it’s understandable if you want to banish lead from your water supply.
Activated carbon filters are incredibly popular methods of water treatment, but how effective are these filters at removing lead?
Some activated carbon filters can remove up to 90% of lead, but not all. Don’t buy an activated carbon filter and just assume that it can remove lead, because this might not be the case.
In this guide, we’ll share how activated carbon filters treat drinking water and what they remove, in what circumstances these filters remove lead, and the best alternative filtration options for lead removal.
Table of Contents
📤 What Are Activated Carbon or Charcoal Filters?
An activated carbon water filter is a type of filter that removes contaminants with the adsorption process.
There are two common types of activated carbon water filters:
- Activated carbon block – These filters are made by compressing carbon powder into a solid block.
- Granular activated carbon (GAC) – These filters are made by pouring loose carbon granules into a filter cartridge or tank.
Carbon block filters typically have much smaller granules than GAC filters – up to 20 times smaller. The small pores of a carbon block filter, combined with the compact nature of the media, allow for slower and more thorough contaminant removal, offering higher purification rates than GAC.
GAC filters have their benefits, though. Because of their loose granule design, they have faster flow rates than carbon block filters, and they tend to last longer, too.
🔃 How do Activated Carbon Filters Work?
Activated carbon filters adsorb contaminants in drinking water. When water flows through the filter media, its contaminants adhere to the surface of the media, and are unable to pass to the other side with water particles.
Because activated carbon filters have a very large surface area, they’re able to trap thousands of contaminants in their pores before replacement filters are needed.
🪨 Do Charcoal Filters Remove Lead?
Standard activated carbon filters don’t offer guaranteed lead removal. This is because lead doesn’t adhere to carbon in the same way that other organic contaminants do.
Look at the filter’s micron rating to work out its lead reduction. Special activated carbon filters with a 1-micron rating should be able to remove most lead from water. That’s because their pores are small enough to physically trap lead, so although lead doesn’t stick to the media, it’s too large to pass through.
In short, some AC filters remove lead, but not all of them.
How to Know if an Activated Carbon Filter Removes Lead
The best way to know whether a carbon filter removes lead is to check for an NSF (National Sanitation Foundation) 53 certification.
If a water filtration cartridge has been certified to this Standard for lead removal, it means it has been third-party tested and proven to reduce lead down to a certain level.
NSF certifications are something to boast about, and most manufacturers share this information as a selling point for their products. You can also use the NSF website to search for a specific brand or product to see if it’s certified.
Carbon water filters don’t have to be officially certified to remove lead, but certifications offer reassurance that a manufacturer’s claims are accurate. Second-best to an NSF certification is third-party laboratory testing to NSF Standards.
If you can’t find any information about certifications or third-party testing, contact the manufacturer and ask for a datasheet to back up their claims.
✅ What Else Do Activated Carbon Filters Remove?
Aside from lead (in some instances), activated carbon water filters also remove:
- Volatile organic compounds (VOCs)
- Disinfection byproducts
Carbon block filters with tiny pores can sometimes go one step further, removing microbiological contaminants, mercury, arsenic, asbestos, and radon from drinking water.
Note: Neither GAC nor carbon block alter water’s total dissolved solids (TDS) rating because they’re only designed to remove specific contaminants, and can’t completely purify contaminated water.
🚰 Alternative Ways to Remove Lead from Water
Activated carbon is a potential option for removing lead and other harmful contaminants from drinking water. But this type of water filter isn’t your only solution.
Other ways to remove lead from your tap water include:
Reverse Osmosis Systems
Reverse osmosis water purification is a guaranteed method of lead removal. This process removes almost all TDS, including volatile organic compounds, some forms of bacteria, free chlorine, arsenic, fluoride, nitrogen, agricultural chemicals, and other heavy metals.
RO systems use a semi-permeable membrane that has a tiny pore size, reducing up to 97% lead.
The downside of reverse osmosis is that it wastes water during the filtration process, and it slows water flow because of the numerous filter stages involved.
Check out this guide to learn about which RO systems are best in 2022
Water distillers are also used to purify water, removing impurities that are harmful to human health.
During the distillation process, water is boiled until it evaporates in a boiling chamber. This water vapor rises and travels down a cooling corridor, before condensing out of the spout. The impurities that can’t evaporate at the same temperature as water – including heavy metals, chlorine, chemicals, fluoride, pesticides, microbes, and other pollutants – all remain in the boiling chamber.
Learn more about the best water distillers for use at home in this post.
The biggest setback of water distillation is that water flow is very slow – it takes up to 6 hours for 1 gallon of clean water to be produced. Distillers also require electricity to operate, and can’t be used for large-scale filtered water production.
🧠 Activated Carbon Lead Removal FAQ
What’s so bad about lead?
Lead is a heavy metal that’s often used in manufacturing. It’s incredibly dangerous if it gets into our drinking water because it’s a cumulative toxicant, meaning it builds up to harmful levels over a period of months or years.
Even tiny amounts of lead are dangerous. According to the EPA, the side effects of drinking lead in tap water include nervous system damage, impaired hearing, learning disabilities, cardiovascular problems, reproductive issues, and decreased kidney function. Lead in drinking water can also cause reduced fetal growth and premature birth in pregnant women.
How does lead get into our water?
There are two common ways that lead gets into our tap water: through industrial discharge and pipe leaching.
Industrial discharge occurs when factories irresponsibly dispose of their waste, and lead leaches into the environment. In some cases, lead can get into surface water or groundwater sources, and isn’t adequately filtered out when it’s treated for public consumption.
Pipe leaching results from lead pipes. When water passes through pipes made from lead, some of the lead leaches into the water. When water sits in lead pipes, it picks up even more lead than running water. Lead was commonly used in plumbing pipes until the late 1980s, when it was banned. However, the ban didn’t affect existing lead pipes, so many of us still get our water from lead supply lines today.
How can you reduce your lead exposure?
Aside from filtering your water to ensure it’s free from lead, you can also reduce your lead exposure by:
- Checking your home for lead pipes and appliances, and replacing these with lead-free alternatives
- Redecorating if you think your walls were painted with lead paint
- Keeping your home clean to prevent an accumulation of lead dust
- Taking steps to keep lead out of your home if your job or hobby involves the use of lead
What can’t an activated carbon filter remove from water?
We know what they can remove, but do activated carbon filters miss? Namely, activated carbon filters can’t remove minerals and salts, heavy metals, and the majority of dissolved inorganic substances. The manufacturer’s website should tell you what a filter can remove. If you’re looking to remove a specific contaminant, and it isn’t listed in the filter’s contaminant reduction description, you know to look elsewhere.
Which filtration removes lead the best?
The more thorough lead filtration removal solution is reverse osmosis. But that doesn’t mean that this type of filter is best for you. A reverse osmosis system is expensive, and it might actually remove more impurities than you want – such as healthy minerals that the human body needs. Carbon filter media is also worth considering, as long as you find a filter with small enough pores to remove lead particles.
Do carbon filters remove heavy metals?
Yes, carbon filters remove heavy metals. But these filters are only designed to remove certain contaminants, and they typically only remove around 50% of heavy metals. You’re best looking at a water purification method like reverse osmosis, if you want to remove as many heavy metals as possible.