Copper is the first metal ever used by humans, first discovered around 9,000 BC it was used to make water pitchers throughout the Bronze Age. Today, you can find this reddish chemical element coating our pennies, water pipes and even in some water purifiers. From copper pitchers to active copper cartridges, this mineral is sometimes used as a disinfectant in the treatment of drinking water.
Copper in water purifiers is a safe and effective non-chemical method of water treatment. Copper is a biocidal agent against waterborne microbes and has been registered in the U.S. Environmental Protection Agency (EPA) as the first solid antimicrobial material. Storing water in copper containers over 16 hours is effective at killing up to 98% of contaminating diarrheagenic bacteria.
In this article, we will explore the positive and negative properties of copper and discuss why it is a good idea to choose water purifiers that contain this metal. When appropriate, we will recommend the best product to ensure the safety of your drinking water.
How does copper affect the body?
Copper naturally occurs in rocks, soil, water, sediment and, to some extent, even in the air. It is present in the human liver as well as in breast milk, where it plays a crucial role in the development of babies.
Yet the human body cannot synthesize copper, so a dietary intake is necessary.
Consuming trace amounts of copper is essential to human health, as it has various biological functions such as helping accelerate hemoglobin formation, and is a fundamental component of human proteins and metalloenzymes (enzyme proteins that contain metal ions).
At the same time, exposure to high concentrations of copper can cause gastrointestinal disturbance including abdominal pain, cramps, nausea, diarrhea and vomiting.
Copper toxicity is rare in healthy individuals, as people are generally exposed to very low concentrations through the water. However, levels higher than the tolerable limit fixed by the U.S. EPA (1.3mg/L) have been detected in drinking water on occasions, especially when there are corroded pipelines and the water is stagnant or partially flushed.
Prolonged exposure can lead to liver and kidney damage, mucous irritation, central nervous problems and other difficulties. Yet accidental poisoning is more likely due to children swallowing copper coated coins.
Is copper safe in a water purifier?
Copper ionization as a non-chemical water treatment is considered a safer and more eco-friendly technology than chlorination, especially when dealing with Legionella bacteria.
The storage of drinking water in copper pots as a purification method dates from ancient times, between the 5th and 6th millennium BC, and is mentioned in early Ayurvedic and Egyptian medicine texts.
This was later scientifically validated when copper and copper alloys were found to be highly effective antibacterial agents after 7 to 8 hours of contact with pathogenic organisms, such as leaving water at room temperature in a copper container overnight.
Other studies suggest that it takes 16 hours for copper to kill all bacteria.
But, it’s important to note, when the raw water contains very high concentrations of bacteria (10,000 colony-forming units of bacteria per ml of water), it is likely to produce leaching of the copper, resulting in water with potentially toxic levels of copper ions beyond the WHO limits.
Thus copper is a slow but excellent antimicrobial agent, capable of killing more than 98% of bacteria after a period that ranges between 7 to 16 hours.
It is still effective when dealing with high concentrations of pathogenic microorganisms, but the resulting water may contain levels of copper that can cause gastrointestinal distress in the short term, and other more serious problems after prolonged consumption.
The Best Water Purifiers With Copper
Surfaces made of uncoated copper or copper alloys (mixtures of metal that have copper as their main component, such as bronze and brass) are great at neutralizing bacteria. The antimicrobial properties of copper surfaces make things like copper dispensers, bottles and even faucets a promising additional tool for the purification of water.
Copper is also introduced into water filter process media such as Kinetic Degradation Fluxion (KDF).
KDF contains high-purity finely granulated zinc and copper alloys that reduce contaminants in water using an oxidation/reduction (redox) chemical reaction. There are two product lines for KDF medium application, both meeting the US EPA and Food and Drug Administration standards for maximum limits of zinc and copper in potable water:
- KDF 55 Medium: designed to remove or reduce chlorine and water soluble heavy metals (including lead, mercury, nickel, and chromium), as well as controlling scale, bacteria and algae.
- KDF 85 Medium: removes or reduces iron and hydrogen sulfide, as well as controlling scale, bacteria and algae.
The best water purifiers that use copper are the ones that combine KDF with other filtration technologies for optimal water quality and safety.
Here are our top recommendations of an under sink, countertop, and reverse osmosis system that use KDF medium (copper) for their antimicrobial properties:
Waterdrop 10UB Under Sink Drinking Water Filtration System
This Waterdrop Ultrafiltration system combines an activated carbon filter and KDF medium with a polyester membrane to effectively reduce chlorine, heavy metals, chemicals, sediment and other large particles.
The KDF media inhibits the growth of harmful substances enabling the filter to last longer. Replacement filters can be purchased in three sizes 8000-, 16000-, or 24000-Gallons that are also interchangeable if you wish to increase or decrease sizes later.
It uses advanced ultrafiltration technology to reduce contaminants including bacteria and other microorganisms up to 0.01 microns.
It comes with a dedicated faucet, and you can easily install it yourself.
It also retains minerals such as potassium, calcium, sodium, and magnesium, so you get better tasting water.
APEX MR-1030 Countertop Water Filter
This APEX KDF-55 Countertop water filter for the kitchen sink combines copper and zinc with granular activated carbon to effectively reduce the most common contaminants found in tap water, such as sediments, hydrogen sulfide, pesticides, chlorine, chloramine, and other harmful chemicals.
It also reduces heavy metals such as lead, iron, and mercury, with four stages of purification, pH balancing, remineralization and taste enhancement.
iSpring 6-Stage Reverse Osmosis System
The iSpring 5-Stage Reverse Osmosis System has three pre-filters that combine carbon technology with KDF copper and zinc medium to remove large contaminants, chlorine and chloramine.
A reverse osmosis membrane removes smaller contaminants, and a post-treatment with granulated carbon polishes the purification process. Finally, an alkaline remineralization filter gives an extra touch to the final taste, alkalinity and mineral content of your drinking water.
Is activated copper harmful?
Activated copper used in water filters is generally safe for human health, as long as it remains within the international standards. The drinking water standards established by the US EPA are 1300 ug/l, copper concentrations that exceed this may cause abdominal pain, nausea, vomiting or other gastrointestinal issues.
Copper is one of the less reactive metals and appears as an active ingredient in copper ionization water treatments and KDF copper-zinc media filters.
The copper content in the KDF filter media, meets the US EPA and Food and Drug Administration standards for maximum limits of zinc and copper in potable water.
Copper-silver ionization is believed to be a safe and effective method to purify water that, as opposed to chlorine and chloramine (most commonly used in water utilities), has no disinfection by-products. The ions released into the water supply, capable of killing Legionella bacteria and other waterborne pathogens, are safe for human consumption and do not cause damage to the plumbing environment.
Still, most water filtration systems or softeners remove copper from tap water.
Is it safe to drink from a copper bottle?
Copper bottles are safe to store drinking water. The antibacterial properties of copper can provide a measure of protection from water borne infections, with 98% of bacteria killed in water left in a copper bottle at room temperature for a period of 7 to 16 hours.
The amount of copper released from the bottle during its storage may provide health benefits, although copper deficiency is not a common concern in developed countries.
This means that most people already get their necessary daily intake of copper with their food (shellfish, seeds and nuts, organ meats, wheat-bran cereals, whole-grain products, and chocolate). Still, the levels of copper that the vessel may release are generally within the tolerable limits determined by the World Health Organization (WHO).
However, when storing highly contaminated water there is a risk of unsafe levels of copper leaching into your water. A simple solution is to store only safe drinking water in your copper bottle, change the water regularly and keep the bottle clean.
Distilled water is slightly acidic, which might enhance copper leaching, as opposed to regular drinking water, and should be avoided.
Another thing to keep in mind is that copper is an excellent conductor of heat, so storing hot water can burn your hands or your mouth when in contact with the metal.
The following copper water bottle is one of the best currently available:
Kosdeg Copper Water Bottle
This copper water bottle by Kosdeg is made of 100% pure copper, without any other metals, alloys or lining, and it comes with a leak proof cap.
It is recommended to use only plain water instead of acidic liquids such as citric juice or coffee, and to avoid filling it with hot or boiling water.
The manufacturer recommends using this copper water bottle in moderation and not storing the same water for more than 6 to 8 hours.