Tap water can contain bacteria, viruses, heavy metals and hormone-disrupting plasticizing chemicals like bisphenol A (BPA). In our increasingly polluted modern environment, using a water filter can help remove as many contaminants as possible from drinking, cooking and shower water.

But are water filters actually proven in studies to reduce contaminants, or do companies just make convincing marketing claims? Which water filter brands are shown to reduce contaminants the most? What contaminants should people be aware of? And are there any water filter brands that should be avoided?

In this article we'll answer all of these questions and more, as we review studies on water filters to determine which successfully reduced the most contaminants.

We'll explain whether or not tap water is really a health concern, and document how one water filter brand may actually add contaminants to water.

Finally, we'll recommend one countertop water filter, one whole-house water filter and one shower filter.

Is Tap Water Actually Contaminated?

A few categories of contaminants in tap water that consumers should be most conscious of are heavy metals, estrogenic plastic chemicals and pesticides.

Heavy metals like lead, arsenic and mercury are present in municipal tap water in many jurisdictions. Although the limits are regulated in the US by the Environmental Protection Agency (EPA), any amount of heavy metal intake is toxic, so limiting exposure as much as possible may be beneficial for health.

Pesticides are also present in tap water, although thanks to efficient water treatment facilities in the US, their levels may actually be lower in tap water than in rainwater, based on environmental studies conducted in New York State.

We also know from medical research that hormone-disrupting chemical bisphenol A (BPA) is present in tap water in many countries. 

Tap water is safe to drink in most parts of the US, but it seems logical for any consumer who can afford it to invest in a research-backed water filter to reduce contaminant intake.  

An excellent exposé by Vox highlighted how a particular type of contaminant called PFAS has become a problem in much of America's water supply, and this is just one type of contaminant that can exist in tap water:

Best Countertop Water Filter

Brita Soho is our top pick for an affordable and effective countertop water filter.

An independent laboratory called ConsumerLab tested several of the leading water filters and found that the Brita Soho With Longlast Filter was the most effective overall.

Brita Soho reduced 100% of the chlorine, 100% of the mercury, 100% of the cadmium and 100% of the lead from the test water, and reduced arsenic by 15.4%.

The most impressive result from the testing was that Brita Soho reduced microplastics in tap water by 100%, and it was the only countertop filter tested that did so.

It's currently retailing for $63.37 with a replacement filter. This ends up costing well under $1 per day for clean drinking water for the whole house.

As the author of this article, I've used a countertop Brita filter for years. The water tastes "purer" and I use it for everything from drinking water to tea to cooking water.

Best Whole-House Water Filter

Aquasana Rhino Whole-House Water Filter is our top whole-house water filtration pick.

When you install a whole-house filter, it filters water in all taps and all showers throughout the house, so it's the most thorough way to remove contaminants.

Aquasana's device is independently tested and certified to reduce toxins, and we haven't come across any tested shower filters, so this seems to be the most effective way to guarantee a reduction of chlorine and chloramine exposure in the shower.

Whole-house water filters have a high upfront cost, but are relatively cost-efficient over long periods of time because of how long they last. 

The Aquasana Rhino filter costs $2,418 at the time of updating this article, but comes with a warranty and is guaranteed to last for 10 years. This equates to a cost of $0.66 per day.

This makes the whole-house filter actually cheaper than purchasing separate countertop and shower water filters over a 10 year period.

Best Shower Water Filter

Many consumers are unaware of this, but exposure to contaminants in water is likely higher during a shower than from drinking water.

This sounds counterintuitive, because drinking water is directly ingested, but chlorine in shower water reacts with organic matter at high temperatures and forms trihalomethanes such as chloroform.

This is proven in medical research, and we know chloroform to be carcinogenic (cancer-causing). These harmful compounds are inhaled and absorbed through the skin during hot showers.

Unfortunately, ConsumerLab hasn’t tested the effectiveness of different shower filters at the time of updating this article, and no shower filter companies we researched published any testing of their products at all.

Sprite SL2-CM Shower Filter is our top shower filter pick because it's easy-to-install (we've used it personally), affordable (only $21.82 currently) and has great reviews.

We would prefer to recommend a shower filter based on test results, but the shower filter industry seems behind the drinking water filter industry in this regard. If a shower filter brand emerges with tests proving its efficacy, we will update this article and recommend it.

As the author of this article, I've used the Sprite shower filter for nearly a decade. I have to replace the showerhead every few years due to rust and/or mold, and replace the filters about twice a year.

I can really tell the difference when a new shower filter is installed. I can't smell the chlorine in the water anymore.

Which Water Filters Should I Avoid?

We recommend avoiding the ZeroWater 6-cup Water Filter Pitcher because ConsumerLab testing found it to actually add microplastic particles to the water samples.

We don’t know how that’s even possible.

Perhaps their filter media contained microplastics that leached out, or the filter itself was made with cheap plastics that leached into the water sample. Regardless, we recommend avoiding this product and brand entirely as this data is concerning.

Conclusion

Contaminants like heavy metals, pesticides and microplastics are present in tap water throughout much of the world, as an unfortunate consequence of pollution.

Water filters can reduce the toxic load on the body by reducing exposure to these toxins in drinking water and shower water.

We recommend the Brita Soho filter for drinking water and the Sprite shower filter. While the Brita has solid research backing, the Sprite doesn’t yet, and we will update this article if tests emerge on the efficacy of shower filters.

We recommend Aquasana's Rhino filter for whole-house water filtration, and believe that whole-house filtration is the most effective and simple way to reduce toxin exposure from water overall.

Tap water should be safe to drink in most regions of the US, but water filtration seems like a logical, affordable choice for most consumers as a precautionary measure.