Are Charcoal Filters Safe? Or, Are There Side Effects?

From filter jugs claiming to purify water to drinking bottles with Bamboo charcoal water filters that attract “contaminants,” there’s a whole new generation of water purifiers claiming to free your drinking water from toxins.

But a question we need to ask ourselves is, “do we really need to use these charcoal filters?”

And in fact, far from being a healthy source of water, could we be inadvertently doing more harm than good by using the filters to clean our water?

In this article, we’ll look into possible charcoal water filter side effects. We’ll also address some of the safety concerns that come with using this water purification method.

Using a Charcoal Filter: What Are the Side Effects?

Generally speaking, it’s quite rare to experience side effects from water derived from charcoal filters. This is because charcoal filters produce some of the cleanest mineral-rich water you can ever get.

However, a quick trip to some forums indicates that users have experienced some adverse effects by using the charcoal-filtered water.

That said, let’s look at some of the more common side effects of using charcoal filter water:

Taste

There is no distinct taste from using a charcoal filter. Only when you don’t.

Without a filter, most water from the city has a distinct chlorine taste and smell.

Normally, water from the tap is chlorinated to kill germs. Unfortunately, a “residual” amount of this substance remains in the water.

Now, if left in large quantities, chlorine can be irritating and usually leaves a metallic taste in the mouth. 

The good news is, the residual chlorine is safe for consumption. Even though there are some side effects, a majority of the users only have an issue with the taste.

Also, it is easier to clear this taste by use of activated carbon water filters that easily draw chlorine from the water.

And while these filter will work fine, you could just let the water lie in the fridge for 12-24 hours, and with time, the chlorine gas will evaporate.

If you have a well, then you may have odors or tastes from the minerals or other matter that the filter can remove.

Filters Can Harbor Bacteria

A recent study has found that carbon filters can harbor bacteria if they’re not replaced often. (Source)

With time, the surface area of the charcoal filter media becomes filled, thus preventing further adsorption of contaminants. Or, in the case of mechanical filtration, the filter media becomes so clogged with debris preventing the effective free flow of water.

While the latter is easier to spot, since the rate of water generated slows down dramatically, it’s not easy to tell when the surface of the filter media becomes full and needs replacement.

Either way, leaving your media filter exposed could be a recipe for bacterial growth, and so, you need to replace your charcoal filters frequently.

You’ll need specific filters to get rid of bacteria. Check out some of the filters below from Amazon to see which one will be best to get rid of your bacteria.

Contaminated Replacement Charcoal

Unlike municipal water, personal filters are usually not subject to any government oversight or regulation, save for NSF International that provides certification and standards.

The lack of any governing body and high consumerism on charcoal filters has led to the abundance of sub-standard charcoal filters in the market.

In case you inadvertently purchase an inferior quality or non-certified replacement cartridge, the results will be sub-standard. It might even introduce impurities in your drinking water. 

Case in point, if the carbon replacement material was not tested for material safety, it can introduce impurities from the materials in the manufacturing process.

Can Charcoal Water Filters Make You Sick?

In general, no they will not make you sick. However, there is one issue.

They may not be filtering things that can make you sick and you will have a false sense of security. It all depends on the quality of the water and what needs to be filtered out.

Now before you decide whether this form of water is right for you, here are some of the health side effects you need to be aware of:

Charcoal Filtration Doesn’t Remove Bacteria

First things first, activated carbon filters are somewhat limited to what they can remove from the water, and if anything, they don’t remove all the nitrates, bacteria, viruses, and dissolved minerals. 

Unlike metals, these components pass through the filters because they’re not bound to the carbon.

That said, the filtered water isn’t necessarily hazardous, and in most cases, the tap water you drink is usually treated to remove bacteria and other organisms, and so, it’s not always a big deal when this stuff slips through.

If you have tested your water and see that you have bacteria like coliform, then you need to use the right kind of filter.

Possible Tooth Decay

Some types of charcoal filters use ion exchange to filter out more contaminants. One of the things it is very good at removing is fluoride.

Some people want the fluoride out of their water but most don’t. If you don’t know that you’re removing the fluoride then there is an increase in risk of tooth decay. You will have to make sure you use a toothpaste high in fluoride to make up the difference. Or, stick with simple charcoal water filters that don’t use ion exchange.

Bacterial Growth

As we had mentioned earlier, unmaintained filters have a detrimental impact on water quality and your health as well.

See, an old filter is not only going to be less effective and slow, but really gross and grimy.

When you don’t replace your filters as required, the filter media might grow mold and impart material such as microbes and bacteria in your water.

So, yes, a charcoal filter can actually add more bacteria in your water. 

This condition is even made worse in the moist environment of the pitcher since it offers the perfect condition for bacteria multiplication, and this can make you sick if you continue using the old filter.

In any case, a German Study found out that the number of bacteria on tap water was significantly less than the amounts in filtered water after several weeks of use. By the end of the study, researchers concluded that the filter media had a biofilm growing on it. In some cases, the bacteria colony was up to 10,000 times more than those in the tap water. 

But can these bacteria make me sick?

It all depends.

In most cases, it won’t but it depends on the type of bacteria. If you have coliform or e coli, and your water supply only has it in small amounts, then the charcoal filter may grow the bacteria to unsafe levels. 

It pays to test your water for coliform before you start using a filter anyway.

What Do Charcoal Filters Remove?

Carbon filters are quite effective at removing and reducing hundreds of chemicals and contaminants.

However, studies by EPA and NFS claim that charcoal filtration is effective at removing between 60-80 chemicals. 

Some of these include chlorine, radon, benzene, solvents such as trihalomethane, and volatile organic compounds such as herbicides and pesticides.

In addition to these harmful components, filters similarly remove the bad taste and odor from the water.

That said, the effectiveness of the purification process is dependent on several factors including the type of carbon used and form of carbon use (GAC or carbon block)

Benefits of Charcoal Water Filters

Here are some of the numerous benefits of using charcoal water filters;

Doesn’t Remove the “Good Stuff”

Unlike other water filtration systems, charcoal water filters do not remove some of the essential minerals and ions that are healthy for our bodies.

The chemical composition and structure of the activated charcoal attracts and absorbs the unhealthy organic compounds, while allowing the healthy minerals to pass and remain in the water.

Unfortunately, this process doesn’t remove all the pathogens and micro-organisms, and it’s for this reason that charcoal filters are used in conjunction with other water filtration methods.

It Makes Water Healthy

As we had mentioned earlier, the charcoal water filter removes plenty of nasty stuff for the water, including the chemicals and compounds.

Even better, activated charcoal can add essential elements such as calcium, iron, and magnesium back into your water, thus improving the overall water quality.

Improves Flavor

Even though the addition of chlorine is necessary to prevent the propagation of bacteria, it usually leaves a metallic taste in the mouth. 

A charcoal filter, however, not only absorbs the nasty smell, but they’re equally effective and removing the odors, hence making the water more palatable.

Cost Effective

Charcoal filters are relatively inexpensive to produce, and unlike other filtration systems, they’re not costly to run.

Easy Maintenance

Sure, the media filters require constant replacement once the charcoal is used, but the good thing is that replacement parts are relatively cheap and easy to install.

Typically, your water media filter should be replaced every six months, but if you’re unsure, look at the clarity of the water and see whether it has changed. Also, you can observe to see whether the taste has changed or whether the flow rate has decreased.

How To Reactivate Activated Carbon

Unfortunately, all good things come to an end, and with time, the activated carbon eventually stops working.

There will be a time when your filter is no longer active, and you may want to reactivate it. Unfortunately, it is not possible to do this yourself at home.

It requires subjecting carbon to temperatures of up to 900 degrees Celsius.

Beyond the heat requirements, there’s also the safety aspect. When the carbon is reactivated, it releases all the adsorbed impurities into the air in the form of vapor. The vaporized impurities are toxic. To prevent the release of these gases into the atmosphere, this process should be handled in an inert gas chamber.

FAQ About Charcoal Filters

Conclusion

Should I use carbon water filters?

In my opinion, carbon water filters are quite effective at removing the hazardous elements form our tap water. Charcoal water filters are as safe as they are effective.

Sure, they don’t get rid of all the elements, and some users claim to experience side effects, but the charcoal water filter side effects are non-harmful, and instances of irritation are far in between.

The most crucial thing, however, is to ensure that you frequently replace your carbon filters because, to me, they appear to be the most prevalent cause of side filter side effects.