WASTE VS. MANURE
"Science now knows that the most fertilizing and
effective manure is the human manure . . .
Do you know what these piles of ordure are . . . All this is a flowering field, it is green grass, it is the mint and thyme and sage . . . it is the guilded wheat, it is the bread on your table, it is the warm blood in your veins."
By dumping soil nutrients down the toilet, we increase our need for synthetic chemical fertilizers. Today, pollution from agriculture, caused from siltation (erosion) and nutrient runoff due to excessive or incorrect use of fertilizers,52 is now the "largest diffuse source of water pollution" in our rivers, lakes, and streams.53 Chemical fertilizers provide a quick fix of nitrogen, phosphorous, and potassium for impoverished soils. However, it's estimated that 25-85% of chemical nitrogen applied to soil and 15-20% of the phosphorous and potassium are lost to leaching, much of which can pollute groundwater.54 This pollution shows up in small ponds which become choked with algae as a result of the unnatural influx of nutrients. In 1992, for example, the state of Florida was required to build some 35,000 acres of marshlands to filter farm-related runoff that was polluting the Everglades.55 From 1950 to 1990, the global consumption of artificial fertilizers rose by 1000%, from 14 million tons to 140 million tons.56 In 1997, US farmers used 20 million tons of synthetic fertilizers,57 and half of all manufactured fertilizer ever made has been used just since 1982.58 All the while, hundreds of millions of tons of compostable organic materials are generated in the US each year, and either buried in landfills, incinerated, or discharged into the environment as waste.
Nitrate pollution from excessive artificial fertilizer use is now one of the most serious water pollution problems in Europe and North America. Such pollution can cause cancer, and even brain damage or death in infants.59 Most cases of infant poisoning occur when infant formula is made with nitrate POlluted water.60 A 1984 US EPA survey indicated that out of 124,000 water wells sampled, 24,000 had elevated levels of nitrates and 8,000 were polluted above health limits (10 mg/liter).61 In fact, a 1990 EPA survey indicated that 4.5 million Americans were POtentially exposed to elevated levels of nitrates from drinking water wells alone.62
The squandering of our water resources, and pollution from sewage and synthetic fertilizers results in part from the belief that humanure and food scraps are waste materials rather than recyclable natural resources. There is, however, an alternative. Humanure and food refuse can be composted and thereby rendered hygienically safe for agricultural or garden use. Much of the eastern world recycles humanure. Those parts of the world have known for millennia that humanure is a valuable resource which should be returned to the land, as any animal manure should.
Farmers know that animal manure is valuable. They know that animal manures are digested crops, and that crops are soil, water, air, and sunshine converted into food, and the best way to use that manure is to put it back into the fields from where it originated. So the farmer loads up the manure spreader and flings the manure back onto the fields, thereby cleaning up his barn, saving himself lots of money on fertilizers, and keeping his soil healthy. Sounds reasonable enough. But what about human manure?
Humanure is a little bit different. It shouldn't simply be flung around in a fresh and repulsive state. It should undergo a process of bacterial digestion first, usually known as composting, in order to destroy possible pathogens. This is the missing link in the human nutrient recycling process. The process is similar to any animal's: a human grows food for herself on a field, or in a garden. The food is consumed and passes into the digestive system where the body extracts what it needs, rejects what it doesn't need at the time, or what it can't use, then excretes the rejected material.
At that moment, the digestive system is no longer responsible for the excretion. It's now time for the brain to go to work. The human mind has basically two choices - consider the excretion to be waste and try to get rid of it, or consider the excretion to be a resource which must be recycled. Either way, the body's excretion must be collected. As waste, the material must be dispensed with in a manner that is safe to human health and to the environment; as a resource, the humanure should be naturally recycled.
In some areas of the world, such as Asia, humanure may be applied raw to fields without being composted beforehand. Containers of human excrement are set outside residences in Asia to be picked up during the night and taken to the fields. The content of these containers is called, appropriately enough, "night soil." That is NOT what this book is about.
Raw humanure carries with it a significant potential for danger in the form of disease pathogens. These diseases, such as intestinal parasites, hepatitis, cholera, and typhoid are destroyed by composting, either when the retention time is adequate in a low temperature compost pile (usually considered to be two years) or when the composting process generates internal, biological heat (which can kill pathogens in a matter of minutes). Raw applications of humanure to fields, on the other hand, are not hygienically safe and can assist in the spread of various diseases which may be endemic to areas of Asia. Americans who have traveled to Asia tell of the "horrible stench" of night soil that wafts through the air when it is applied to fields. For these reasons, it is imperative that humanure always be composted before agricultural applications. Proper thermophilic (heat-producing) composting destroys possible pathogens and results in a pleasant-smelling material. Low temperature composting, given adequate time, will yield a compost also suitable for agricultural purposes.
At the very least, raw night soil applications to fields in Asia do return humanure to the land, thereby recovering a valuable resource which is then used to produce food for humans. Composted humanure is used in Asia as well. Cities in China, South Korea, and Japan recycle night soil around their perimeters in greenbelts where vegetables are grown. Shanghai, China, a city with an expected population of 14.2 million people in 2000,63 produces an exportable surplus of vegetables in this manner.
Humanure can also be used to feed algae which can, in turn, feed fish for aquacultural
enterprises. In Calcutta, such an aquaculture system produces 20,000 kilograms
of fresh fish daily.64 The city of Tainan,
Taiwan, is well known for its fish, which are farmed in over 6,000 hectares
of fish farms fertilized by humanure. Here, humanure is so valuable that it's
sold on the black market.65
Source: The Humanure Handbook. Jenkins Publishing,
PO Box 607, Grove City, PA 16127. To order, phone: 1-800-639-4099.