I was under the impression that organic crops could not use any pesticides. So I was surprised to learn in the Wikipedia entry that they can in fact use pesticides as long as they are natural.
It is a common misconception that organic agriculture does not use pesticides. Some pesticides used on organic farms contain inorganic copper - and since copper is not biodegradable, this can lead to toxic copper accumulation in the soil. Approved organic pesticides are relatively less effective and must be applied at high levels (e.g. copper salts, sulfur) or must be applied frequently (e.g. pyrethrin). Other toxic pesticides that are approved for use by organic producers include ryania, Sabadilla, and rotenone.This site explains more:
Contrary to what most people believe, "organic" does not automatically mean "pesticide-free" or "chemical-free". In fact, under the laws of most states, organic farmers are allowed to use a wide variety of chemical sprays and powders on their crops.As loyal Fat Knowledge readers are aware, I am not a big fan of the term "natural". First, natural is a vague term that can easily be manipulated. Second, lots of people equate it with healthy, and that is just not true. Hemlock is natural, but I sure ain't going to drink it. Spider venom is natural, but it sure isn't healthy for humans. Smoking tobacco leaves is natural, but it still causes cancer (and probably more than all "non-natural" items combined).
So what does organic mean? It means that these pesticides, if used, must be derived from natural sources, not synthetically manufactured. Also, these pesticides must be applied using equipment that has not been used to apply any synthetic materials for the past three years, and the land being planted cannot have been treated with synthetic materials for that period either.
The question shouldn't be whether they are natural but how healthy they are for humans and the environment. And what is the verdict on "natural" pesticides?
When you test synthetic chemicals for their ability to cause cancer, you find that about half of them are carcinogenic.Great, so about 1/2 of natural pesticides are carcinogens, and rather than actually test them they get a free ride due to their natural status. Hopefully they will do some testing and figure out which pesticides are the healthiest for humans and animals in the surrounding area and use them. Until then, maybe we need a "Pesticide-Free" Organic label. :)
Until recently, nobody bothered to look at natural chemicals (such as organic pesticides), because it was assumed that they posed little risk. But when the studies were done, the results were somewhat shocking: you find that about half of the natural chemicals studied are carcinogenic as well.
This is a case where everyone (consumers, farmers, researchers) made the same, dangerous mistake. We assumed that "natural" chemicals were automatically better and safer than synthetic materials, and we were wrong.
When you look at lists of pesticides allowed in organic agriculture, you find warnings such as, "Use with caution. The toxicological effects of [organic pesticide X] are largely unknown," or "Its persistence in the soil is unknown." Again, researchers haven't bothered to study the effects of organic pesticides because it is assumed that "natural" chemicals are automatically safe.