Systemic are those pesticides that spread in all plant tissues, for example passing through the peel to reach the fruit pulp.
These plant protection products, in fact, are absorbed by the roots or leaves and from here, carried by the sap, they spread in the rest of the organs of the treated plant.
Unfortunately, therefore, removing the peel of a fruit drives away most of the interferers, but does not guarantee the complete removal of all pesticides.
In the photo kiwi with and without peel. Kiwi is absolutely one of the fruits with the lowest presence of pesticides
