Cryptosporidium is a surface water contaminant that’s known to cause a waterborne disease called cryptosporidiosis.
Here, we’ve shared our top 5 methods of removing cryptosporidium oocysts from drinking water.
📌 Key Takeaways:
- Cryptosporidium is a parasite that’s found in sewage systems and the fecal matter of infected humans and animals.
- If it contaminates drinking water supplies, cryptosporidium causes cryptosporidiosis, with symptoms including diarrheal and stomach cramps.
- The best methods of removing cryptosporidium from water are reverse osmosis, ceramic filters, absolute 1-micron filters, UV purifiers, and water distillation.
Table of Contents
- 🤔 What Is Cryptosporidium & Where Does It Come From?
- 🩺 Potential Health Effects of Cryptosporidium
- 🧪 How To Test For Cryptosporidium In Water
- ✅ How to Remove or Kill Cryptosporidium from Drinking Water
- ⚗️ Does Boiling Water Remove Cryptosporidium?
- 🥇 Which Water Filters Are Best For Cryptosporidium Removal?
🤔 What Is Cryptosporidium & Where Does It Come From?
Cryptosporidium (known as “crypto” for short) is a protozoan parasite that enters surface water supplies through sewage overflows, agricultural runoff, and direct contamination of fecal matter.
In its egg-like form, cryptosporidium is known as cryptosporidium oocysts.
Public water systems may contain low levels of cryptosporidium. Chlorine disinfection, a common method of drinking water treatment, is not an effective way to kill this parasite. Variations of disinfection with chlorine dioxide and ozone are moderately effective, but are still unlikely to kill cryptosporidium entirely.
Cryptosporidium has a tough outer shell that is often resistant to treatment with chlorine-based disinfectants.
🩺 Potential Health Effects of Cryptosporidium
The most likely outcome of drinking water containing cryptosporidium is a diarrheal disease called cryptosporidiosis.
Some of the symptoms of this disease are:
- Watery diarrhea
- Nausea and vomiting
- Stomach pain
- Dehydration
- Fever
- Weight loss
An infected person may experience these cryptosporidiosis symptoms for 1-2 weeks after contracting the disease. In some cases, cryptosporidiosis may occur for long periods, recurring at intervals over a period of 30 days or longer.
People with compromised immune systems may suffer serious health effects as a result of contracting cryptosporidiosis.
🧪 How To Test For Cryptosporidium In Water
You can’t see, taste, or smell cryptosporidium in water, which means that the only way to know whether or not your water contains this parasite is to conduct a test.
DIY test kits aren’t capable of detecting cryptosporidium. You’ll need to pay for a laboratory test with a more complex testing process. Lab testing kits often cost upwards of $500 because of the difficulty of testing for crypto.
To use a laboratory test kit to detect cryptosporidium in your water, follow these steps:
- Order the test kit online and wait for it to arrive at your home.
- Use the included sample vials and follow the instructions to take a sample of water from your faucet.
- Mail the sample back to the laboratory.
- Wait for your test results (usually within 10-14 days), which will be delivered to you via email or post.
Because of the high cost, we don’t recommend testing for crypto in your water unless you have a private well and somebody in your home has contracted cryptosporidiosis – and you’ve ruled out all other possible causes of this disease.
If you get your water from a municipal supplier, ask to see recent testing from your water utility rather than spending your own money.
✅ How to Remove or Kill Cryptosporidium from Drinking Water
Here, we’ve shared our top 5 recommended methods of removing cryptosporidium with an at-home water treatment system:
Reverse Osmosis System
Cryptosporidium removal effectiveness: >99%
Reverse osmosis is one of the most effective methods of removing cryptosporidium from drinking water.
RO systems use a treatment process called membrane separation to separate impurities from water molecules. This process takes place in a semi-permeable membrane, which has a pore size as small as 0.0001 microns.
Cryptosporidium is about 3-4 microns in size. So, when this parasite comes into contact with the semi-permeable membrane, it’s unable to filter through the pores, and rebounds back into the RO chamber. Here, the cryptosporidium is flushed down a drain with wastewater.
Reverse osmosis systems are the best water treatment systems for folks who want to protect their families from cryptosporidium and the majority of other tap water contaminants, including bacteria, viruses, heavy metals, chemicals, and giardia cysts.
You can buy a reverse osmosis water filtration system for $300-$650. Under-sink and countertop RO systems are popular choices.
1-Micron Absolute Filter
Cryptosporidium removal effectiveness: >99%
A standard water filter won’t filter out cryptosporidium or any other waterborne pathogens because these tiny contaminants will simply slip through the filter’s pores along with the water molecules.
However, a water filter with a 1-micron rating should have small enough pores to block cryptosporidium and prevent it from passing through with water.
There are two types of filter micron ratings: absolute micron rating and nominal micron rating.
When looking for a water filter that can remove cryptosporidium effectively, look for absolute micron filters. These filters will provide consistent cryptosporidium removal, while a nominal 1-micron filter (which has pore sizes as small as 1 micron) may allow 20-30% of cryptosporidium to slip through.
You can find 1-micron absolute filters in portable water filters designed for filtering backcountry water sources (such as straw filters and hanging gravity filters), as well as some countertop water filters and water filter pitchers.
Depending on the filter type, the upfront cost for a 1-micron absolute filter is anything from $30 to $250. You will need to replace the filter when it becomes saturated with contaminants, usually after 2-6 months.
UV Purifier
Cryptosporidium removal effectiveness: >99.99%
A UV purifier is a point-of-entry water treatment system that doesn’t remove crypto from water, but instead deactivates this parasite and prevents it from reproducing and causing disease.
When water flows through the UV chamber, the ultraviolet light penetrates the cell walls of harmful microorganisms and scrambles their DNA, rendering them incapable of causing harm in an infected human.
There have been concerns over the effectiveness of UV purification to treat water containing cryptosporidium. However, if your water is non-turbid and you have a strong UV light, it should effectively deactivate up to 99.99% of crypto in your water.
The average cost of a POE UV light, which treats your whole home’s water supply, is $1,000-$1,300.
Ceramic Water Filter
Cryptosporidium removal effectiveness: >99%
Ceramic water filters have a pore size that’s as small as 0.3 microns, which means they’re another effective method of removing cryptosporidium in drinking water.
These water filters have a network of tiny pores on a ceramic cartridge, which trap contaminants as water molecules pass through.
As well as cryptosporidium, ceramic filters can remove pathogenic bacteria, giardia lamblia, and (if the filter contains an activated carbon core), chemicals like chlorine and PFAS.
Make sure to check the pore size of a ceramic filter before you buy it, and check the test results to see what it removes.
You can find ceramic filters in countertop water filter systems, under-sink water filters, and portable filters, costing $50-$150 on average.
Water Distiller
Cryptosporidium removal effectiveness: >99%
A water distiller boils water until it vaporizes, then condenses it into a separate container, leaving the contaminants behind in the boiling chamber.
This countertop unit is another highly effective method of addressing crypto in water because boiling water kills this microorganism.
Distillation is considered a water purification method because it eliminates virtually all water impurities, including bacteria, viruses, chemicals, and heavy metals.
However, the distillation process takes hours, so a water distiller isn’t the best solution for you if you want near-instant access to crypto-free drinking water.
The average cost of a countertop water distiller is $250-$400.
⚗️ Does Boiling Water Remove Cryptosporidium?
No, boiling water doesn’t remove cryptosporidium – but it is a highly effective method of killing cryptosporidium, which means you can use this method to make crypto-contaminated water safe to drink.
To kill cryptosporidium by boiling the water, follow these steps:
- Fill a pot with drinking water and put it on your stove on a high heat.
- Wait for the water to reach a rolling boil.
- Let the water boil for at least 1 minute.
- Transfer the water to a clean storage container and wait for it to cool before drinking.
Boiling water is a good option if you just need a short-term solution to safe drinking water and you don’t want to buy bottled water. You can also use this method if your local authority issues a boil water notice due to the detection of cryptosporidium in the water supply.
🥇 Which Water Filters Are Best For Cryptosporidium Removal?
The best water systems for cryptosporidium removal depends on your personal situation.
For instance, if you’re not restricted by budget and you want to remove as many contaminants as possible from your water, RO systems are probably your best choice.
Otherwise, if removing cryptosporidium is your main goal and your budget is smaller, consider more affordable treatment methods, like ceramic filters and absolute 1-micron filters. However, you will need to consider additional treatment if you ever decide that you want to remove a greater number of contaminants in the future.
We recommend asking yourself a few questions before you start shopping, including:
- How much do I want to spend upfront and on yearly filter replacements?
- What are my installation and maintenance preferences?
- What’s my preferred filter use point? (i.e. under-sink, countertop, whole home)
- Do I want to remove any other contaminants alongside cryptosporidium?
- Do I know of any contaminants or water parameters (e.g. turbidity) that could affect a filter’s ability to reduce protozoan parasites like cryptosporidium?
Regardless of the filter type you choose, we recommend looking for an official NSF Standard 53 or Standard 58 certification for cyst reduction or removal, which tells you that the filter has been third-party tested and deemed capable of performing according to the manufacturer’s claims.
Do cold temperatures kill Cryptosporidium? If its in a public water system, at what outdoor temperature is it likely to be gone? Thanks.
Cryptosporidium cysts can only become inactivated rapidly when exposed to temps −20 °C (-4 °F) or below.