A U.S. Department of Agriculture survey of produce that found nearly 20 percent of organic lettuce tested positive for pesticide residues piqued our interest. Lots of the lettuce contained quite a bit of spinosad, a pesticide marketed by Dow Chemical under the brand name Entrust.
When people are buying organic food, they often make the incorrect assumption that there are no pesticides. It’s true that organic production often uses fewer dangerous chemicals, but certain pesticides are allowed.
It turns out that a key factor in chemicals being cleared for use on organic crops is whether they occur naturally. Spinosad, for example, comes from the soil bacterium Saccharopolyspora spinosa. It can fatally scramble the nervous systems of insects. It’s also poisonous to mollusks.
Read the whole story at NPR.com