Of the 256 mostly synthetic pesticide active substances allowed only in conventional agriculture, 55% carry health or environmental hazard warnings; for the 134 natural active substances that are also allowed in organic agriculture, only 3% do. Warnings about possible harm to the unborn child, suspected carcinogenicity, or acute lethal effects were found in 16% of the pesticides used in conventional agriculture, but in none of the pesticides approved for organic use. Setting health-based guidance values for acceptable occupational or dietary intake was considered appropriate by EFSA for 93% of conventional but only 7% of natural active pesticides substances.

“The differences we found are as significant as they are unsurprising when one takes a closer look at the origin of the respective pesticide active substances,” says Helmut Burtscher-Schaden, biochemist at GLOBAL 2000 and lead author of the study: “While around 90% of the conventional pesticides are of chemical-synthetic origin and underwent screening programs to identify the substances with the highest toxicity (and thus highest efficacy) against target organisms, the majority of the natural active ingredients are not even ‘substances’ in the strict sense, but living microorganisms. These make up 56% of the pesticides approved in organic farming. As natural soil inhabitants, they do not have hazardous substance properties. Another 19% of organic pesticides are classified from the outset as ‘low-risk active ingredients’ (e.g. baking powder, ferric phosphate) or approved as basic substances (e.g. sunflower oil, vinegar, milk).”

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