Can You Grow Food With Human Waste?

Fertilizer is an essential component of any flourishing horticultural project. Fertilizer provides added or supplemental nutrients to help plants reach their fullest potential – sort of like the human need for vitamins and minerals. 

Manure is the most popular and easily accessible fertilizer. Many farmers employ elaborate manure collection procedures and spread it across their crops to promote healthy growth.

You most likely consider manure as strictly sourced from animals, but some farmers are moving towards human waste due to a lack of resources.

So, can you use human poop to grow food? Read on for more information on the fertilizer of the future.

Pile of manure of a farm being processed

Can You Grow Plants With Human Feces?

The short answer is yes! You can grow plants with human feces. There are organizations within the United States currently making this abundant source of fertilizer more practical than ever. 

If the idea of using human waste as fertilizer makes you cringe, do not worry – farmers and agricultural manufacturers do not use untreated human waste. Sewage and other potentially dangerous sources are not the collection points for fertilizer.

Untreated Human Feces

Repurposing human waste is not a new practice. Deemed night soil, many cultures use human excrement as fertilizer for crops. Night soil has been used with great success, starting in the vast agricultural fields of ancient China.

However, like most practices of yore, its longevity does not mean it is healthy. The feces used by ancient cultures were untreated and often packed with diseases. Feces is a waste product developed by your body to expel everything it does not need. 

If used as fertilizer, the dangerous bacteria and pathogens in untreated human poop can seep into soil and crops – and become fatal. 

Treated Human Feces

Today, farmers implement human feces to grow plants and vegetation under careful supervision and study. In the United States, human waste goes through an extensive process regulated by the Environmental Protection Agency (EPA).

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The EPA describes benefits such as water reuse, affordability, and improved overall soil structure. Once the human poop reaches the EPA standards, it becomes a biosolid. Nearly half of all of the biosolids in the United States end up on large agricultural plots of land and our beloved public forests. 

Biosolids do not resemble human feces. The extensive treatment process turns the solid waste into sludge combined with rainwater and other wastewater. Human waste must experience at least one round of EPA-approved treatment protocols before it becomes a biosolid.

The treatment process involves removing pathogens and reducing odor by adding healthy bacteria. Then, the waste becomes a Class B biosolid and is safe when used with care in specific situations where the remaining pathogens will not cause harm. 

The second treatment implements high heat to kill any remaining damaging substances leftover from the initial Class B procedures. Following the heat treatment, the human waste becomes a Class A biosolid and is safe for use in any garden, field, or other horticultural activity. 

Class A biosolids typically end up in agricultural manufacturing plants, national forests, parks, or community gardens. Organizations such as the U.S. Composting Council strive to get this nutrient-rich fertilizer to growers while debunking myths about using human waste.

Is Human Poop Toxic?

The primary issue with using human poop as fertilizer is, well, poop is gross – and most people do not want to think about their fruits and veggies growing in human waste.

Gardeners and growers have issues with the concept, as they get up close and personal with their soil and may worry about odors or illness.

The Illinois Poison Center states feces is considered nontoxic. This advice is available in the event of a small child encountering the product and ingesting it whole or from residue under their fingernails.

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The waste mentioned in the nontoxic-versus-toxic debate is untreated human waste – that looks and smells like poop.

Treated BioSolids

However, treated biosolids look like any other fertilizer you would see at the store. Once growers master the mental hurdle of using feces fertilizer, applying it for everyday farming and gardening will become much less arduous.

In addition to the ickiness of being wrist-deep in human poop, applying waste to plants promotes concern. Many growers ask themselves, is human poop toxic? Do I want to put everything someone has ever ingested into the flowers, herbs, vegetables, and other plants I am trying to grow?

Using human waste as fertilizer may seem off-putting, but consider the number of unknown toxins in your water, cosmetics, and even the air in your home that you inhale or ingest daily. A few of the toxic materials you likely encounter are: 

  • Chloroform – found in tap water
  • Parabens – preservatives used in makeup that cause cancer
  • Pesticides – used on grocery items to prevent bug infestations

The bottom line? Human waste as fertilizer endures much more testing than the other products we use every day.

A 2009 EPA report found evidence of harmful residue from pharmaceuticals, steroids, and other chemicals in 74 random samples – much less than what you discover in treated human feces.

How Can You Use Human Feces?

If you are motivated to repurpose your waste, you’re in luck. There are several creative ways to put your poo to use. 


Nowadays, composting toilets are gaining followers for personal use and large-scale applications, such as music festivals. Cabins in remote areas also utilize composting toilets. Composting toilets can cost about $80 to $130, but you can DIY your composting toilet for much less.

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Are you wondering how a composting toilet works? Here is how the earth works its magic: 

  1. You pee or poop into a large bucket, similar to a port-o-potty.
  2. A natural filter such as sawdust, sugar cane residue, or rice goes over your waste to diminish the smell and encourage decomposition.
  3. Once filled, empty the waste into a large bin that can withstand temperatures above 250 degrees Fahrenheit.
  4. The contents naturally develop into compost that you can use for plants. Do not use your untreated waste for any foods you plan to eat raw.

It takes time for your compost to evolve fully, but it is a beneficial material that can help cut down on excess water usage.

Bio Fuels

Cultures worldwide use human waste for fuel daily. Nations like Ghana, Rwanda, and China have not only exceeded their hesitation for using biological waste – they surround themselves with the product.

So, how do you create biofuel from human poop? The process is surprisingly simple. Without oxygen, human waste breaks down and gives off gasses like carbon dioxide and methane. 

These byproducts can be captured and used as renewable energy. In Rwanda, prisons seek to save money on firewood by heating prisons with biogas from the waste of inmates.

Medical Procedures

Poop transplants are legitimate medical advancements used to help treat serious diseases.

Some patients become so ravaged by medical treatments and sickness that they need healthy bacteria reintroduced into their bodies to fight off customary threats.

Diseases like C. difficile, commonly known as C. diff., can kill patients by weakening their immune systems (potentially to death). C. diff, which causes chronic diarrhea, can be treated using a fecal transplant to help the patient gain strength and fight back.