One of the world’s greatest mathematicians and physicists was Isaac Newton. Newton’s third law of motion loosely translates that for every action, there is an equal and opposite reaction.
The pedestrian application of this law is that if you push someone, they will push back, or with every food you eat, you have to generate waste.
Every human, regardless of age, has to generate waste. The process of eliminating human waste depends on the region, seeing that some countries use sewage systems, and others are not so lucky.
However, is it possible that we can all use human waste to improve our gardens? This article focuses on human poop and how it can be composted.
Is Human Waste Compostable?
Human waste is compostable, although the composting process will differ depending on the location where the process is taking place. For instance, human waste should not be added to the general home compost bin unless adequately managed. A composting toilet can do the job for you, even if it is at home.
On the other hand, it is generally safe to compost human waste at an industrial composting plant. The main reason why composting human waste at home in your composting bin is discouraged is because of the harmful bacteria and pathogens that could be present in the waste.
To effectively kill them, hot compost is therefore advised and is primarily absent in most domestic composting bins. However, if yours is a hot one, go right ahead.
Human waste is rich in plant-healthy nutrients, making it ideal for growing your crops, especially as fertilizer or compost. However, it also contains viruses, pathogens, and bacteria that the standard home composting process cannot effectively remove.
This makes composting human waste using such domestic bins unsafe for the process in general and also for vegetables, berries, fruit trees, and other edible plants. This is why a composting toilet is advised, although it also has its own rules about composting human waste.
Alternatively, use large-scale composting facilities, which have the technology and heat to process the waste at high temperatures for a lengthy period. The resulting product is heavily regulated and frequently tested by the Environmental Protection Agency (EPA) to ensure bacteria and pathogens are below detectable levels.
Where the waste is approved, it makes for perfect fertilizer that can improve soil quality and reduce the dependence on chemical fertilizers.
There are expert composters who argue against using composted human waste on edible plants, primarily because of the slight chance that dangerous bacteria are still alive in the human waste.
This is absolutely true, and you should avoid using human waste or composted human waste as fertilizer on your edible plants, fruits, or other plants.
The only time such compost can be completely safe is if it undergoes a hot compost and all the harmful pathogens are killed in the process. The pathogens and bacteria can live through the waste, be taken up by the edible plants, and end up in your system once again.
The only safe place to take the uncomposted waste, other than the sewerage system, is burying it. If you have to use it, apply it to non-edible plants.
Otherwise, wait for the fecal matter to go out, then compost it, or take it to an industrial plant and hot-compost it before applying it to edible plants or crops.
Can You Use Human Poop as Fertilizer?
Yes, human poop can be used as fertilizer. In fact, it has been used for a similar purpose for centuries. According to JSTOR, in eighteenth-century Japan, human excrement played a vital role in agriculture.
In fact, the potential use of human excreta as a fertilizer in agricultural fields can be an incentive for people to collect and treat fecal sludge so it can be used to increase soil health.
Unfortunately, prejudice and lack of knowledge have stood in the way. The application of human excreta-derived fertilizer (HEDF) in agriculture does not pose a risk of pathogens or heavy metals.
However, according to a group of scientists from the School of Water, Energy, and Environment at Cranfield University in the UK, local regulations and perceptions can be a problem.
Dried human feces are high in phosphorus, potassium, and some micronutrients. This is why human excrement has been proven to have an excellent fertilizing potential, providing essential plant nutrients as well as organic matter, contributing towards building soil structure and reducing erosion.
Where the excreta is treated appropriately, like composted under the appropriate heat, and killing all pathogens, the poop will make for a good fertilizer that is safe to use for agricultural purposes. Unfortunately, not so many farmers or gardeners prefer to use such bio-solids as fertilizer due to the prejudice imposed on them.
Luckily, since they have a positive effect on the soil, farmers might not discriminate against such a fertilizer.
The primary risk associated with using human poop as fertilizer is the potential disease-causing pathogens present in the poop, as well as the antibiotics, hormones, and endocrine disruptors that appear in such manures.
Is Human Faeces a Hazardous Waste?
Human waste is not hazardous waste, although it requires additional care before using as fertilizer or before composting. Human feces can be classified as hazardous if they contain dangerous diseases and bacteria such as cholera, rotavirus, E. coli, pinworms, norovirus, hepatitis, and dysentery, among others.
These conditions are dangerous and, at times, fatal, meaning the fecal matter will be a biohazard. However, human waste is not classified as medical waste, so there have to be additional regulations on how such material is handled.
They also require proper disinfection by experts specializing in human waste clean-up because of the high exposure risk to infectious diseases.
Failure to clean up such waste can result in similar health conditions affecting those cleaning the waste. It might also result in litigation in different jurisdictions.
Generally speaking, hazardous waste is any waste that presents a substantial threat to public health or the environment. It is illegal to dispose of both hazardous and non-hazardous waste at the same landfill site in several jurisdictions, for the hazardous waste will affect the land, underground sources of water, nearby rivers, and, of course, the environment in general.
Also, depending on the toxicity of the hazardous waste, it could be between dangerous and fatal to humans, animals, and birds living next to or coming into close contact with the landfill.
The most common items described as hazardous include certain paints, inks and pigments, solvents, pesticides, electric waste, and vehicle fluids, among others.
Human waste, luckily, does not fall under such a category, although a lot of caution should be exercised when handling fecal matter that contains bacteria or diseases like those mentioned above.
Rather than considering human waste as hazardous, it is best to classify it as offensive waste. Offensive waste is any waste that is non-infectious but may be unpleasant or cause offense to those who come into contact with it.
Offensive waste includes condoms, urine, vomit, medical or veterinary waste, incontinence pads, sanitary waste, nasal secretion, sputum, and, of course, human and animal feces.
The moment you meet with any of these waste, they will offend you and could be even so if you are a member of certain religions.
A common misconception about offensive waste is that because it is not technically hazardous, it may be placed into general waste as long as it is done with caution. This is incorrect, and you should separate such offensive waste from other general waste and put it in an offensive waste bin.
How Long Does It Take for Human Waste to Compost?
The duration upon which human waste composts is entirely dependent on the composting process used.
1. Cold Composting
This is the classic composting process and can easily be done at home. Here, organic matter is collected and exposed to weather conditions, usually at temperatures not higher than 40°C.
With such temperatures, the composting process is particularly slow. It can be slower if either the weather conditions do not facilitate the process or the contents inside the composting bin are placed improperly.
Composting human waste using the cold composting process will take months, and pathogens in the fecal matter will not be destroyed.
2. Vermicompost
This is the composting process where earthworms are introduced into the mix. The worms can eat and digest 1.5 times their body weight per day, and since they inherently dig through everything, they are best suited to breaking down organic matter.
Unfortunately, fecal worms, even if the name suggests otherwise, do not like direct contact with human feces. Composting using worms creates a lot of moisture, which can then drain to a certain extent. The worms also feel most comfortable at temperatures not beyond 30°C.
The method of composting fecal matter also relies on a neutral pH inside the composting bin. Additionally, urine should not get into the worm compost as the ammonia in urine can kill the hard-working worms. Where the process is done well, it can take a few months, but a slightly shorter time than when cold-composting
3. Hot Composting
Hot composting involves construction, rebuilding, and reduction phases. The entire process can take about 20 days and is the sure way to kill all pathogens and eggs present in fecal matter.
It is the best way to ensure human waste is composted properly and can be used on edible fruits and food crops as the matter undergoes high temperatures of about 65°C.
How Do We Dispose of Human Waste?
Advancements in life have enabled us to eliminate our waste through toilets. Toilets are available all over the world and require enough water for proper running. Unfortunately, there are some areas where such water may be unavailable, there are breaks in the sewer line, or the toilets are inaccessible entirely.
Of all ways to dispose of trash, human waste should never be disposed of with regular trash and should be placed in a separate waste bag.
In doing so, such waste can then be taken to the municipal, city, or local composting facilities that use hot compost and come up with compost that is safe for use on edible crops.
You can also come up with your own makeshift toilet where you use a plastic bucket and seat lids.
There are also portable or camp toilets that can be purchased and the mechanism to empty them is easy once they fill up. Another thought is to look for compostable toilets that have a mechanism on how to eliminate or compost human waste with ease.
You can also look for commercially made waste bags that contain powdered absorbent and bacterial enzymes that break down human waste, allowing the entire bag to be disposed of in regular trash. However, you will still need a bucket and seat lid for when a toilet is not available.