Agricultural storage facilities get in contact with a lot of different pesticides. On the one hand, insecticides are directly applied in the silo to control pests. On the other hand, pesticides are applied on the crops and are thereby transported into the collection centres.
The results of a FiBL Project in 2014 suggested that pesticides most probably accumulate on and in concrete silo walls over years. Thus, stored organic cereals and oilseeds could be contaminated with prohibited substances. Since some pesticides are very persistent under the dry conditions in the collection centres, a possible contamination may happen years after their last application. This may lead to cases of pesticide-residues in products, where the cause is not clearly evident.
Bio Suisse