Sunday, May 23, 2010

Evidence of the benefits of organic food

Defining the benefits of organic food has largely been left to word of mouth, occasional media coverage, and the promotional efforts of organic advocates. Even though many large food and beverage corporations, like Kraft Foods, have rapidly moved to acquire significant stake in both fresh and processed organic products, the specific sales points of "organics" go largely unmentioned on product packaging and in advertising.

These comparisons need to be evaluated with care because neither conventional nor organic farming practices are uniform.
For the environment
In several surveys that have looked at smaller studies to build an overall comparison between conventional and organic systems of farming a general agreement on benefits has been built. In these surveys it has been found that:
*Organic farms do not release synthetic pesticides or herbicides into the environment - some of which have the potential to harm local wildlife.
*Organic farms are better than conventional farms at sustaining diverse ecosystems. That is, populations of plants and insects, as well as animals.
*When calculated either per unit area or per unit of yield: Organic farms use less energy and produce less waste - waste such as packaging materials for chemicals.
See "Organic FAQs" in the journal Nature for more details.
One study found a 20% smaller yield from organic farms using 50% less fertilizer and 97% less pesticide. Studies comparing yields have had mixed results. Supporters claim that organically managed soil has a higher quality and higher water retention. This may help increase yields for organic farms in drought years. One study of two organic farming systems and one conventional found that, in one year's severe crop season drought, organic soybean yields were 52% and 96% higher than the conventional system and organic maize yields were 37% higher in one system, but 62% lower in the other. Studies are also consistent in showing that organic farms are more energy efficient.
For producers
For those who work on farms, there have been many studies on the health effects of pesticide exposure. Even when pesticides are used correctly, they still end up in the air and bodies of farm workers. Through these studies, organophosphate pesticides have become associated with acute health problems such as abdominal pain, dizziness, headaches, nausea, vomiting, as well as skin and eye problems. In addition, there have been many other studies that have found pesticide exposure is associated with more severe health problems such as respiratory problems, memory disorders, dermatologic conditions, cancer, depression, neurologic deficits, miscarriages, and birth defects. Summaries of peer-reviewed research have examined the link between pesticide exposure and neurological outcomes and cancer in organophosphate-exposed workers.
For consumers
A study publish by the National Research Council in 1993 determined that for infants and children, the major source of exposure to pesticides is through diet. A recent study in 2006 measured the levels of organophosphorus pesticide exposure in 23 school children before and after replacing their diet with organic food. In this study it was found that levels of organophosphorus pesticide exposure dropped dramatically and immediately when the children switched to an organic diet.
Most conventionally grown foods contain pesticides and herbicide residues. There is controversial data on the health implications of certain pesticides. The herbicide Atrazine, for example, has been shown in some experiments to be a teratogen, even at concentrations as low as 0.1 part per billion, to emasculate male frogs by causing their gonads to produce eggs effectively turning males into hermaphrodites.
The US Environmental Protection Agency and state agencies periodically review the licensing of suspect pesticides, but the process of de-listing is slow. One example of this slow process is exemplified by the pesticide Dichlorvos, or DDVP, which as recently as the year 2006 the EPA proposed its continued sale. The EPA has almost banned this pesticide on several occations since the 1970s, but it never did so despite considerable evidence that suggests DDVP is not only carcinogenic but dangerous to the human nervous system especially in children.

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