The European Food Safety Authority (EFSA) has published a report that investigates the occurrence of 21 active substances frequently present in organic products that are not compliant with organic regulations, and identifies possible reasons for their presence in organic foods.

The 21 active substances included in the report are not naturally occurring, and are not authorized for use in organic production, but have been or are approved for use in plant protection products. 

For each substance, several potential sources of residues were identified, such as the accumulation of residues in soil, the transfer of residues from water sources used for irrigation, and spray drift from conventional crops. Since some of the substances are registered as biocides or veterinary medicines under REACH, these uses may also release residues in the environment that may be transferred from the environment to plants and to food/feed commodities

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