Composting Human Waste: Our Complete Guide

composting human waste
With the proper safety measures and hygiene practices, you can compost your poop to produce human waste compost that’s excellent for your plants and soil. Consider a compost toilet for your home or outhouse to help you with proper waste collection and management for your compost pile. 

It’s advisable not to add solid, unprocessed human waste directly to your compost pile until you understand the proper steps to safely and hygienically manage it and make it suitable for compost. 

The Best Way to Compost Human Waste: A Step by Step Guide

Remember that organic material isn’t 100% safe when composting human waste.

Always follow the proper steps to ensure most disease-causing pathogens are killed. 

Various methods are involved in composting human waste depending on the duration intended for the composting process. 

Step 1. Install Your Composting Toilet and Bin

Your first step would be ensuring you have a properly functioning composting toilet with the bin installed. 

It’s best to compost poop from a urine-diverting composting toilet. These toilets come with two chambers, one collecting only feces while the other collecting urine. 

For the perfect composting conditions, the waste material collected must be slightly damp and not diluted with urine or water.

Alternatively, you can use an outhouse because if the contents are too wet, proper composting will be difficult, and the resulting compound will stink.

Step 2. Place the Collected Waste in a Dedicated Composter

Do not place unprocessed poop directly in your compost pile. 

Instead, use a dedicated composter specifically designed to handle human waste. 

The container should have lots of ventilation, mustn’t leach out the bottom or sides, and should be placed away from rain or snow.

A rotating compost bin is one of the best solutions to ensure all requirements for a bin are met. 

Step 3. Add Mulch or Green Plants to Your Bin

Once you start composting, you can add nitrogen and carbon-rich materials such as grass clippings or vegetable waste. 

Adding these nitrogen-rich organic materials creates the perfect conditions for thermophilic bacteria to prosper in your bin.

Ensure you don’t overdo the additions because you might make the contents too damp. 

Step 4. Monitor Your Bin Regularly

While you don’t have to open the bin daily, monitoring its content occasionally is wise. 

If the contents seem too wet, you can add sawdust or dry leaves and grass to absorb the moisture.

On the other hand, if the contents are too dry, you can add some water or nitrogen-rich green plants. 

Always ensure the contents are only slightly damp for the best composting conditions. 

Step 5. Add the Resulting Contents to Your Compost Pile

You should never add composted human waste directly to your plants. 

Always add it to your compost pile first for further composition and to neutralize the intensity of any remaining pathogens.

Comparably, never use human waste compost on edible plants because dangerous bacteria could still exist even after composting. 

How Long Does It Take for Human Waste to Compost?

The time taken to compost human waste varies depending on the method chosen, including:

1. Hot Composting

This process involves 3 phases, construction, rebuilding, and reduction, which takes about 20 days to kill all dangerous bacteria, pathogens, and eggs in feces.

It would help if you had a proper-sized compost bin to ensure your compost heats up sufficiently, which is average, four feet wide, and high. 

The sun is your primary heat source for this method, and any shade can slow down the process. 

High temperatures of about 65°C must be reached to properly decompose the waste and make it suitable for fruit trees and food crops. 

2. Vermicompost

This composting process involves introducing earthworms into your compost bin to help speed up the composting process.

These vermin eat and digest about 1.5 times their body weight daily and are also effective at breaking down organic matter in soil due to their constant burrowing behavior. 

Nonetheless, worms function best at temperatures below 30°C and, thus, might not prosper much when in direct contact with human feces. 

Vermicomposting creates excess moisture, which can only be drained to a specific limit. 

Similarly, the success of this method requires a neutral pH inside your composting bin, which cannot be achieved with urine present. 

The ammonia in urine kills the worms making it harder for them to speed up the composting process through vermicompost.

It can also take a few months to compost your waste using the vermicomposting method.

3. Cold Composting

Cold composting is the most commonly used method to decompose human waste in a compost bin because it’s simple.

This method involves exposing the organic matter to temperatures below 40°C, which can take months for the composting process to complete.

Yet, the major drawback of using this method is that the pathogens in your poop aren’t entirely broken down, making it riskier. 

The World Health Organization, WHO, guidelines recommend that you must compost human waste for six months before using it as a fertilizer for your plants. 

This duration is best for destroying any STH eggs and larvae, posing a threat to public health. 

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Composting human waste using a compost toilet

Can You Eat Vegetables Grown in Human Waste?

Yes, you can eat vegetable-grown in human waste as long as the poop was composted correctly using the proper steps. 

You cannot eat any food crops grown in fresh manure or poop because the waste material may contain harmful bacteria that contaminate your plants and cause diseases when consumed.

Proper composting using high temperatures helps these dangerous bacteria that could otherwise cause various diseases through your food. 

Large-scale composting facilities have the technology and heat to compost human waste under high temperatures for extended periods efficiently. 

The products from these facilities have been approved and regulated by the EPA Environmental Protection Agency to ensure they’re effective at reducing bacteria and pathogens to a minimum. 

Yet, it’s best to avoid using human waste compost as fertilizer for your edible plants because the poop may still contain traces of dangerous bacteria even after proper composting. 

What Is Human Waste Compost Good For?

Human waste compost has various benefits, including:

  • It’s rich in plant-healthy nutrients like potassium and phosphorus, which are essential in making fertilizers. 
  • It ensures your soil maintains sufficient water levels and reduces the need for irrigation. 
  • It reduces the carbon footprint contribution by wastewater treatment plants through toxic chemicals. 
  • It’s an excellent water conservation solution that ensures less water is wasted through flush systems creating more options for scarce drinking water.
  • Compostable toilets provide a better sanitation solution in areas without electricity and water.

However, as much as human waste compost is good for plants, it also contains harmful pathogens and bacteria that can affect people when consumed in edible plants. 

What About Urine in Composting Human Waste?

Large quantities of urine in your compost bin have enough ammonia to slow the composting process but not enough to stop it. 

Feces have less ammonia than urine, and you can, thus, decompose human waste faster.

Still, urine is a sterile compound that quickly evaporated using the exhaust fan of modern composting toilets. 

Urine also contains high nitrogen content that’s good for your garden soil. 

You can opt to install a composting toilet that comes with two separate chambers, one of which is designated for urine disposal.

Are Human Feces Good Fertilizers?

Yes, human feces have good fertilizing potential because they provide your plants with essential nutrients and organic matter that contribute to improving soil quality.

Still, using unprocessed human waste as fertilizer is risky due to the existing pathogens; you must use a proper composting process to kill any dangerous bacteria.

Why Is Poop Used as Fertilizer?

There are instances whereby unprocessed human waste is used as fertilizer, especially when the demand for fertilizer skyrockets or in places with poor-quality soil. 

Still, using night soil and human waste manure as fertilizer is risky because the unprocessed poop contains disease-causing microorganisms or pathogens.

The night soil commonly has worm infections like ascariasis, whose eggs in the feces are transmittable between infected and uninfected people. Yet, some developing countries still use night soil, but the risks are stagnant.

The secreted material needs proper composting to reduce the risks of using poop as a fertilizer. 

What Is the Role of Bacteria in Composting Poop?

Bacteria are chemical decomposers of human waste in compost bins. 

These bacteria break down organic matter to produce moisture, heat, carbon dioxide, humus, and stable organic matter.

The human waste is converted into valuable minerals, and with the introduction of microorganisms in the compost pile, it’s transformed into organic fertilizer. 

Can Worms Compost Human Feces?

Yes, you can use worms in your compost pile to help compost human feces better and faster.

Even so, you must ensure the waste involved comes in solid form because the presence of excess urine kills the worms and affects the entire process.

Different techniques exist for vermicomposting, and the most common one involves getting a vermicomposter and adding the worms to it with the waste material. 

Vermicomposting is a preferred method because it helps reduce the number of pathogens in poop by about 60%, including Salmonella and e-coli. 

Without these pathogens in your compost pile, you’re free to use the composted waste as fertilizer for your plants. 

Still, you can always leave the poop outside for about a year before composting to ensure it’s safe for use and all pathogens have died.

Is Human Poop Considered a Hazardous Waste?

Human feces isn’t classified as hazardous waste. Still, it must undergo additional processes and be under extra care before being safe for use as a fertilizer. 

Poop can only be hazardous if it has dangerous bacteria causing bacteria and illnesses like rotavirus, pinworms, cholera, e—Coli, dysentery, and hepatitis, among others.

These underlying conditions are dangerous and can be fatal to anyone that comes into contact with the concerned feces and thus, considered a biohazard. 

Still, since human waste isn’t medical waste, there aren’t any regulations on handling the organic material, and, therefore, it is legal to use in your compost pile. 

You should always ensure you’re wearing the right gear when composting human waste in a compost pile because feces can be dangerous, unlike regular compost material like cardboard.

Can I Use Toilet Paper in My Composting Toilet?

Yes, you can!

Your composting toilet will benefit from adding any toilet paper.

Toilet paper is made of natural material and is a good source of carbon which helps reduce the odor from the feces and maintain the required pH. 

It would help if you never dumped diapers, tampons, or wipes into the composting toilets or bins. 

Most of these forbidden products are made from non-organic materials and toxic chemicals that prevent them from decomposing and can also affect the state of your compost. 

What Are the Costs for a Composting Toilet?

Depending on your supplier, a self-contained composting toilet can cost about $1,400 or more.

We know what you’re thinking… $1,400 isn’t cheap! Well, compared to a fully functional traditional toilet with a flush system and its septic tank, it’s very affordable. 

A septic tank system alone can cost you about 75% more than the original price of a self-contained compost toilet. 

If you’re more of a handy guy, on the other hand, you can opt for a DIY approach which could cost you a stunning $50. Unbelievable right?

Nonetheless, you must install an outdoor composting bin before constructing your composting toilet. 

Most necessities for a DIY composting toilet are standard, including cover material for the waste, bucket, sawdust or shavings, plywood, medical-grade toilet seat, and other assorted hardware. 

Break the Waste Cycle

We artificially create nutrients to grow our food, consume it, defecate, and throw our excrement away, thus, polluting our environment while spending billions on trying to save it. 

This endless cycle is highlighted in The Humanure Handbook, one of the most brilliant creations by Joseph Jenkins that explains how to break the waste cycle for our good effectively. 

Take a moment to appreciate this guide to human waste composting and read the book to get a clearer picture of what you’re signing up for and the good it can do for you. 


Discovering composting as a way of life or even better, as nature’s way of recycling, Ana dedicates her time to trying out new methods of composting at home. Her goal is to share everything that she’s learned in the hopes that it will help others discover the amazing rewards of composting.

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