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Water purification tablets are the packable solution to a big environmental problem: unsafe drinking water. According to a recent report by the WHO and UNICEF, 2 billion people (worldwide) lack access to safely managed drinking water at home, and nearly 8 out of 10 people who continue to lack basic drinking water services live in rural areas. Although it may be a no-brainer to treat water in remote, rural areas, it’s also an important consideration when hunting, camping, or hiking. A seemingly pristine river, alpine lake, or backcountry stream could also be hiding pathogens, so it’s essential to resist the urge to fill up your water bottle and take a sip without first disinfecting the water. 

Common types of water treatments include filtration, ultraviolet light, and tablets for water purification, but a combination of these methods is best. However, water purifying tablets are the easiest (and often the most portable) way to produce safe drinking water outdoors, and are an excellent backup option in case of an emergency. 

Water purification solutions can come in tablet, liquid, or powder form, and when used correctly, these treatments are safe for consumption. We’ve researched all three types and found the best water purification tablets for remote hiking, camping, hunting, and fishing.

Things to Consider Before Buying Water Purification Tablets

Before purchasing water purification tablets, there are factors to consider such as the active ingredients, taste, the time it takes to purify the water, and what pathogens the purification system is protecting you from. Keep in mind that water purifying tablets are designed for use in freshwater, and will not work on salt water. 

Active Ingredients

Water purifying products primarily use chlorine dioxide, sodium chloride, or iodine as the main purifying agent. When used as directed in very small quantities to disinfect water, these mineral and chemical compounds are generally considered safe to consume. According to the CDC, around 5 percent of large water-treatment facilities in the United States use chlorine dioxide to treat drinking water. 

However, when mistaken for medications, vitamins, or candy and consumed whole, water purification tablets can be poisonous and lead to a variety of uncomfortable gastrointestinal (and other) side effects. It’s also worth noting that because disinfecting products are considered pesticides, they must be registered with the EPA for use in the United States. 

Time to Purify

The time it takes for tablets and drops to purify water depends on the product itself, as well as the temperature of the water, and can range from 35 minutes to four hours (specifically, when treating for Cryptosporidium). A general consensus across products has shown that cold water takes longer to purify than warm or hot water. All products decontaminate water in one step. However, while some are also able to neutralize flavor and color in the same step, others require a second step to complete that process, which can extend the time it takes to make water potable by a few extra minutes. 

Protection Type

Not all purification tablets treat for the same thing. Chlorine dioxide kills bacteria, viruses (such as enterovirus, hepatitis A, norovirus, and rotavirus) and protozoan cysts like Cryptosporidium and Giardia—parasites that cause diarrheal diseases. These pathogenic bugs can be found in water contaminated by human and/or animal feces. Chlorine dioxide has also been used by municipal water treatment plants to kill a variety of waterborne pathogens since the late 1940s. 

Sodium chloride and iodine are effective against Giardia and several types of bacteria and viruses. Always check the packaging of the product to ensure it offers the protection you’re looking for.

Best Overall: Potable Aqua Chlorine Dioxide Tablets

Best Overall

Why it Made The Cut

The potable aqua chlorine dioxide purification tablets are a solid choice for hiking, camping, and hunting, thanks to the ultra-portable packaging and ability to improve the taste and clarity of drinking water in a single step.

Key Features

  • Quantity: 30 individually-packaged tablets
  • Time: One tablet purifies one liter of water in four hours
  • Active ingredient: Chlorine dioxide

Pros

  • Low-profile wrappers take up minimal space
  • Meets EPA microbiological purification standards
  • Made in the USA 
  • Excellent rating in the Better Business Bureau (BBB)

Cons

  • Longer purification time
  • Not suitable for long-term daily use

The Potable Aqua Chlorine Dioxide Water Purification Tablets offer safe drinking water in recreational and emergency situations. When used as directed, they’re effective against bacteria, viruses, and cysts such as Giardia and Cryptosporidium. In addition, Potable Aqua Chlorine Dioxide tablets meet EPA microbiological purification standards.

According to the manufacturer, these tablets have demonstrated between four and seven times the biocidal activity of equivalent doses of sodium hypochlorite, have more than double the oxidizing capacity of chlorine, biodegrade in the environment, and do not generate harmful byproducts. The one drawback, however, is it takes four hours to work—so a little advanced planning is needed if you’re out on the trail. 

Parent company Wisconsin Pharmacal Company and the Potable Aqua brand have donated to global relief efforts where clean water is needed. The tablets are made in the USA with both domestic and imported materials. 

Best Value: Potable Aqua Water Germicidal PA+ Tablets

Best Value

Why It Made The Cut

The potable aqua water purification tablets with PA+ Taste Neutralizer are our pick for best value because of their affordability and flavor/color neutralizing option.

Key Features

  • Quantity: 50 tablets per bottle
  • Time: Two tablets from each bottle can purify one liter in 35 minutes
  • Active ingredient: Tetraglycine hydroperiodide

Pros

  • Stored in recyclable glass bottles
  • Made in USA 
  • Removes iodine taste
  • Quick purification

Cons

  • Two-step process to purify and neutralize
  • Not suitable for long-term daily use

Potable aqua water germicidal PA+ tablets are a lightweight and affordable backup for filters, but can be used alone for emergency disinfection to treat drinking water of questionable bacteriological quality. This two-step water purification system purifies water in just 30 minutes, with an additional five minutes to reduce color/flavor of the iodine treatment with the PA+ neutralizing tablets.

The potable aqua purification system is EPA registered and is effective against bacteria, viruses, and many cysts such as Giardia. However, it is not effective against Cryptosporidium cysts. The tablets are made in the USA and are packaged in small, recyclable glass bottles.

Best Iodine: Coghlan’s Two-Step Purification System

Best Iodine

Why It Made The Cut

Coghlan’s two-step drinking water purification system offers a neutralizer to eliminate the taste and color of notoriously unpleasant iodine treatment.

Pros

  • Made in the USA
  • Excellent rating in the BBB
  • The majority of paperboard packaging utilizes recycled content

Cons

  • Not suitable for long-term daily use
  • Two-step process to purify and neutralize
  • Iodine treatments take longer in cold water
  • Doesn’t protect from all pathogens 

Coghlan’s two-step drinking water system is ideal for wilderness and backcountry activities as well as emergency preparedness, and can quickly treat water in 35 minutes. Plus, this affordable iodine treatment kit includes germicidal purification and neutralizer tablets, making biologically questionable water safe to drink with no iodine taste or color. The system is EPA registered as a water purification product and protects against Giardia and bacteria.

Coghlan’s is a family-owned business headquartered in Winnipeg, Canada (with a U.S. presence as well) that specializes in outdoor equipment. The brand works with US-based organization Opportunity Partners to offer adults with special needs and disabilities a chance to participate in a traditional work environment by providing jobs packaging Coghlan products.

Best Tasting: Katadyn Micropur M1 Purification Tablets

Best Tasting

Why It Made The Cut

Katadyn Micropur M1 purification tablets have a lightweight and low-profile packaging that fits in the tiniest space in your pack. Plus, they don’t leave you with an unpleasant aftertaste.

Key Features

  • Quantity: 30 individually packaged tablets
  • Time: One tablet purifies one liter of water in four hours
  • Active ingredient: Chlorine dioxide

Pros

  • Low-profile foil wrappers take up minimal space 
  • Protects against several bacteria and viruses
  • Minimal taste

Cons

  • Longer purification time
  • Not suitable for long-term daily use

The Katadyn Micropur M1 Purification Tablets result in fresh-tasting water that is effective against several types of microorganisms, bacteria, protozoa, viruses, and cysts—including Cryptosporidium. If you plan on spending a lot of time in the woods around a basecamp and don’t need the tablets to be immediately purified, these EPA-registered tablets are a great choice. The longer purification time (four hours) means that you’ll need to treat them at the campsite or in your car while you’re out exploring, but you’ll come back to clean drinking water without an aftertaste.

Katadyn is a brand under The Katadyn Group, a global corporate group headquartered in Switzerland (although the tablets are produced in Germany) with a broad portfolio covering self-sufficient nutrition and drinking water supply. The brand participates in humanitarian and emergency relief efforts around the world by offering water purification and filtration systems. 

Best for Survival: PURINIZE Water Purifier Drops

Best for Survival

Why It Made The Cut

Purinize water purification drops reduce/inactivates more than 200 biological and chemical contaminants and is even safe for daily use.

Key Features

  • Quantity: Two-ounce bottle of drops
  • Time: 20 drops purify up to one liter of water in one hour
  • Active ingredient: Mineral salts

Pros

  • 100 percent non-toxic and chemical-free
  • No chemical aftertaste
  • Made in the USA

Cons

  • Slightly longer purification time
  • Plastic bottle dispenser 

Purinize is a 100 percent natural, mineral-based water purifier that disinfects and clarifies questionable water from any freshwater source. Its formulation of mineral salts eliminates or reduces contaminants including pathogens (bacteria, viruses, and protozoa) as well as heavy metals, industrial and agricultural chemicals, pharmaceuticals, and more. Purinize is EPA registered and meets NSF/ANSI standards. When stored correctly, it does not expire and is safe for consistent, daily use.

Purinize uses a combination of methods to purify: reduction-oxidation to convert compounds into less-toxic particles, and coagulation-flocculation to remove suspended pollutants. This causes them to clump and settle, but can easily be removed with a cloth or paper filter. 

The Michigan-based company donates water purification products to programs in Haiti and Belize (with certain customer purchases).

Best for Traveling: Aquatabs Water Purification Tablets

Best for Traveling:

Why It Made The Cut

Aquatabs water purification tablets are our pick for traveling to a location where clean drinking water is a legitimate concern thanks to the variety of water-borne diseases these effectively treat.

Key Features

  • Quantity: 100 individually packaged tablets
  • Time: One tablet purifies up to 22 ounces of water in 40 minutes
  • Active ingredient: Sodium dichloroisocyanurate

Pros

  • Low-profile wrappers take up minimal space and travel well
  • Effectively purifies smaller bottles of water
  • Very affordable for a large number of tablets

Cons

  • Wrappers are not easily recyclable 
  • Not suitable for long-term daily use

Aquatabs water purification tablets are ideal for traveling as well as for outdoor activities and emergency preparedness thanks to their ability to kill 99.99 percent of Giardia cysts, cholera, typhoid, dysentery, and other water-borne diseases. The tablets dissolve quickly and result in clean-tasting water in just 40 minutes. Tablets are individually packaged to preserve freshness and have a 4- to 5-year shelf life. Aquatabs tablets are EPA-registered and meet NSF/ANSI standards

Aquatabs is headquartered in Ireland, and its parent company Kersia is ISO 9001 and GMP certified (for quality management practices). The company works with local partners and NGOs to bring sustainable water disinfection solutions to target communities struggling with access to fresh water.  

Best for Large Quantities: Aquamira Chlorine Dioxide Water Treatment

Best for Large Quantities

Why It Made The Cut

Aquamira’s chlorine dioxide liquid treatment is designed for treating water in bulk and is ideal for water storage for recreational or emergency use. It’s great for RVs, too!

Key Features

  • Quantity: Two-ounce bottles
  • Time: Both bottles purify up to 60 gallons of water in 15 minutes
  • Active ingredient: Chlorine dioxide

Pros

  • Stored in recyclable glass bottles
  • Also offered in unbreakable, travel-friendly packaging 
  • Quick purification time
  • Made in the USA

Cons

  • Difficult to use for smaller doses without optional droppers
  • Not suitable for long-term daily use

Aquamira chlorine dioxide water treatment is an excellent choice for treating larger quantities of water thanks to its two-part system that makes it easy to treat large tanks and containers of up to 60 gallons. This liquid purification method takes just 15 minutes, but effectively kills illness-causing bacteria and enhances the taste of stored water. Unlike iodine or other treatments, Aquamira won’t discolor water and can actually improve its taste. 

The product itself has a four-year shelf life when stored correctly and sealed, treated water is good for five years. Plus, Aquamira’s liquid formula controls the buildup of slime in water storage containers. 

Aquamira is headquartered in Logan, Utah, and has an excellent rating with the BBB. In addition, the company has been recognized for its humanitarian efforts in providing access to clean and safe drinking water around the world.

Product Comparison 

BrandAntisepticFormat# of StepsTreatsTime
Potable AquaChlorine DioxideTablets11L4 hours
Potable AquaTetraglycine HydroperiodideTablets21L35 minutes
Coghlan’sTetraglycine HydroperiodideTablets21L35 minutes
KatadynChlorine DioxideTablets11L4 hours
PurinizeMineral SaltsDrops11L1 hour
AquatabsSodium DichloroisocyanurateTablets122oz40 minutes
AquamiraChlorine DioxideDrops260gal15 minutes

How We Made Our Picks 

We combed through more than two dozen water purification solutions and narrowed it down to products with the easiest guidelines for how to use the tablets/drops, best shelf life, those with minimal taste, recyclable packaging, and EPA registration, while, most importantly, focusing on safety and effectiveness of the products and the bacteria and viruses they can treat against.

The products above cover different antiseptic types and purification times. Special consideration was given to companies with humanitarian and emergency aid programs, as well as products made in the USA. We also evaluated European brands that produce products domestically but have a North American presence.

FAQs

How much do water purification tablets cost?

Water purification tablets and drops range from approximately $8 to $40 depending on the number of doses in the package. Some brands offer a small discount for products purchased in multi-packs or bulk. They’re very affordable, even more so when you’re able to maximize usage before the expiration date.

Do water purification tablets expire?

Tablets and drops used for water purification do expire, although most have a shelf life of up to five years when properly stored in the original packaging. Individually-packaged doses are less likely to degrade over time, as opposed to exposing an entire bottle of tablets to air every time it’s opened. It’s important to pay attention to the expiration date because the efficacy cannot be guaranteed once expired, and the effects of drinking contaminated water can range from unpleasant to lethal.

Water purification tablets vs boiling: is one better than the other?

According to the CDC, boiling water is the most effective method to kill viruses, bacteria, and parasites in water used for drinking, cooking, and cleaning. However, bringing a heating element along on an adventure isn’t always possible, and what happens if it breaks? When boiling isn’t an option, water purification tablets are an excellent backup.

According to Howard D. Backer, MD, MPH for the Wilderness Medical Society, water brought to a rapid boil should be adequately disinfected in seconds, but boiling for one minute is recommended by the CDC to add a margin of safety.

How effective are water purification tablets?

Tablets for water purification are very effective at treating for microorganisms; however, the active ingredient determines which microorganisms it is most effective for. How do water purification tablets work? They use chemistry to purify water, which is why you’ll see sediment drop to the bottom of the container being treated. For the best results, combine tablets with a portable filter to catch solid matter.

Are water purification tablets safe?

Water purification tablets are designed to neutralize contaminants, making water safe to drink, brush your teeth with and wash your hands. Generally, water purifying tablets and drops are safe, but there are some additional considerations. For example, most of these types of products are not designed for extended daily use. Water purification tablets are only necessary to treat water from questionable sources and aren’t needed for public drinking water that has already been processed. 

According to the National Capital Poison Center, when used excessively, water purification treatments can cause immediate irritation of the mouth, throat and stomach, resulting in a burning sensation, nausea, abdominal pain and vomiting. Iodine-based purification can result in delayed effects if used over a longer period of time. The risks of poisoning depend on a variety of factors, so it’s important to follow the instructions for use to minimize risk.
 
In addition, not everyone can use water purification tablets. For example, iodine tablets can present health risks for people with thyroid conditions, iodine allergies, and pregnant women.

How should I dispose of the water purification packaging in the backcountry?

When space is at a premium, these treatment systems won’t take up much room. Plus, most of the packaging is recyclable, making it easy to drop it in the nearest recycling bin when you pack out your waste. Properly disposing of waste is one of the 7 Principles of Leave No Trace, a comprehensive guideline to ensure your outdoor adventures have minimal impact on outdoor spaces for wildlife, waterways, and people.

Final Thoughts

The Natural Resource Defense Council states that contamination cannot be contained by a line on a map and that transboundary pollution—including industrial, agricultural, and municipal discharge—is a real issue. Untreated water can harbor dangerous germs that can turn an idyllic outdoor experience into something out of a horror story. 


So, whether you’re looking to treat water for an RV, a campsite full of kids, or to keep yourself safe on the trail, any of these water purification drops or tablets could be a great choice to have as a backup. However, the Potable Aqua Chlorine Dioxide Tablets meet EPA microbiological purification standards, giving them the edge as the best overall choice. Or, if you’re looking for a natural option, consider the Purinize Water Purifier Drops for outdoor activities, travel abroad, and emergency situations.