Monday, January 12, 2009

Know Your Shit...Manure and Antibiotics

By Al Brooks

In our embrace of organic farming, we used to shun chemical fertilizers, and rightly so. They do harm to soil microorganisms and produce bloated crops with less flavor and nutrition. But some new studies have uncovered problems with manure, our favorite fertilizer for organic crops, that now cause us to examine where a particular batch of manure comes from and what went into the livestock that produced it.

According to tests conducted at the University of Minnesota, many food crops absorb the antibiotics leaching into the soil from the manure of livestock fed these chemicals. Antibiotics are introduced into livestock feed in order to increase growth and prevent infections. We have long understood the environmental harm, done by the application of excess manure, to our waterways because of runoff. But the researchers at the University of Minnesota discovered that vegetables such as corn, potatoes and lettuce absorb antibiotics when grown in soil fertilized with livestock manure.

Close to 70 percent of the total antibiotics and related drugs produced in the United States are fed to cattle, pigs and poultry, according to the Union of Concerned Scientists. And about 90 percent of that is excreted in the urine and manure. According to an article in Rachel's weekly #993:

"The Minnesota researchers planted corn, green onion and cabbage in manure-treated soil in 2005 to evaluate the environmental impacts of feeding antibiotics to livestock. Six weeks later, the crops were analyzed and found to absorb chlortetracycline, a drug widely used to treat diseases in livestock. In another study in 2007, corn, lettuce and potato were planted in soil treated with liquid hog manure. They, too, accumulated concentrations of an antibiotic, named Sulfamethazine, also commonly used in livestock."

Heat (cooking and canning) and other processing can reduce the levels of some antibiotics in foods, but Sulfamethazine, for one is not affected by heat. Of greatest concern are those vegetables that are commonly eaten raw, like lettuce and cabbage, and those tubers that are in contact with the soil and may absorb greater quantities, like potatoes, carrots, and radishes.

Health officials fear that eating vegetables and meat laced with drugs meant to treat infections can promote resistant strains of bacteria in food and the environment. Past studies have shown overuse of antibiotics reduces their ability to cure infections. Over time, certain antibiotics are rendered ineffective. But scientists have evidence that there may be other serious consequences. Antibiotics also may have contributed to the explosive rise in asthma and allergies in children over the last 20 years. Again, quoting from Rachel's Weekly:

"Researchers at Henry Ford Hospital in Detroit, following 448 children from birth for seven years, reported that children who received antibiotics within their first six months had a higher risk of developing allergies and asthma."

"Such health concerns led the European Union (EU) in 2006 to ban antibiotic use as feed additives for promoting livestock growth. But in the United States, nearly 25 million pounds of antibiotics per year, up from 16 million in the mid 1980s, are given to healthy animals for agriculture purposes, according to a 2000 report by the Union of Concerned Scientists."

Composting of manure, since heat is generated by this process, can break down some of the antibiotics. But if a farmer or gardener wishes to be free of this contamination entirely, s/he must know the pedigree of the manure applied to the food crops. Until we put in place regulations similar to those in the EU, where antibiotics can be given only to sick animals, we must each, individually apply the precautionary principle and avoid using even "natural" fertilizers whose source is unknown.


  1. I am certainly in agreement with the article's content regarding the
    > prevalence of synthetic antibodies present in livestock manure.
    > Unfortunately, the USDA National Organic Program (NOP) does not have
    > restrictions on the sourcing of animal manures at this time. At the time
    > the rule was written and promulgated (2002), it was "believed" (narrowly
    > defined) that animal manures from organically managed sources was not
    > commercially available to all who needed it. Therefore, animal manures
    > can come from any source and the growers that use it from any source can
    > still be certified to the USDA standard--provided the application of these
    > manures is consistent with Section 205.203 of the standard.
    > The EU organic standard requires that the source of manure may not come
    > from CAFO's but may still contain antibody residues if the manure came
    > from livestock in need of immediate medical attention--which is the
    > variance allowed for sick livestock that the article below describes in
    > the last paragraph.
    > However, since the NOP is a government program subject to due process and
    > public comment, this rule CAN BE CHANGED!! It will be an arduous process
    > and the likelihood of this rule changing may be minimal. But, it will
    > most certainly take a concerted effort among all who are concerned to
    > change the way this rule (CFR 205.203) is currently written. If we think
    > the NOP is WORTH salvaging and changing to better ensure the longevity and
    > sustenance of our land and water based ecosystems and the health of our
    > livestock and the public at large, then we need to be confident that our
    > efforts can bring about the positive change we seek. This can and should
    > apply to all of the current language in the USDA National Organic Final
    > Rule (CFR 205) that we think does not address our current and future
    > physio-ecological crises.
    > It really depends on whether or not we think the USDA/NOP is the
    > appropriate medium by which we regulate the organic products we produce
    > and consume and how relevant such a program can be to meet our current and
    > future socio-ecological demands. Otherwise, there is really no reason to
    > support market-based organic horticulture/agriculture as it is defined by
    > the USDA today.
    > For those who do want to make the USDA program work for us, there are at
    > LEAST two potential ways to accomplish this:
    > 1. Build a movement of your peers and network with relevant organizations
    > to petition the NOP to amend the current rule to regulate how organic
    > growers source animal manures.
    > 2. Attend quarterly National Organic Standards Board meetings to persuade
    > the NOSB to make recommendations to the NOP to change the way Section
    > 205.203 is written as it applies to the acquisition and utility of animal
    > manures.
    > 3. And, of course, one can never leave out potential/relevant direct
    > action initiatives.
    > I am always available to discuss such attempts...

  2. Great Article Post Simply Wonderful....

    Smith Alan