Munich - Only 11 per cent of farming areas are arable land. Unfavourable weather, desiccation, salinisation and climate change are further threats to crop yields. To feed the current global population of 7 billion, pesticides are used around the world. TÜV SÜD's food experts provide information on residue levels in food products and give tips on buying local and seasonal produce.
Plant protection products, also known as pesticides, are essential for maximising crop yields. Around 500 different chemicals with extremely varied spectra of activity are currently approved in the EU. Herbicides, which control the growth of undesired plants, make up the largest class of substances. Fungicides protect plants against fungal diseases, whereas insecticides protect them against harmful insects. Some individual chemicals are even approved for use in organic farming.
As inexpert application of these substances may have far-reaching consequences for people and the environment, their approval, sale and use in the EU is subject to strict regulations. Germany, for example, continuously monitors the maximum residue levels (MRLs) in food and feed products. Food products are tested and analysed as sold, i.e. with skins and without prior washing or cleaning. "With very few exceptions, the data obtained in government monitoring show that residue levels of individual substances were generally not unsafe for people", says Dr Andreas Daxenberger, food expert at TÜV SÜD. Germany's Federal Office of Consumer Protection and Food Safety, for example, analyses data from thousands of samples taken from retailers, farms and importers throughout the various German states.
To date, a total of over 17,000 samples have been tested for pesticide residues. Strawberries, table grapes, green salads and other food products that have showed high residue levels in the past are checked more frequently. On average, 38.5 per cent of all samples were found to be completely free of any measurable pesticide residues. In 58.3 per cent of the samples the food supervisors measured residues below the maximum residue level. 3.2 per cent of the samples contained residue concentrations above the defined maximum level which, however, are not associated with any health risk. The percentage of samples containing residues above the maximum residue level has decreased over recent years. Today, pesticide residues have become insignificant in potatoes, asparagus, onions, cauliflower, broccoli and other brassicas. The same goes for baby and infant foods and organic food products. In terms of pesticide residues, organic products fare even better than conventional food products. Interested consumers can contact the food safety authority in their German states to obtain specific information on residue analysis.
However, individual chemicals are only one side of the coin. "When it comes to the question of how to avoid and how to assess the health impacts of multiple pesticide residues in a food product, further studies are needed", says Daxenberger. Studies should aim at understanding how a combination of multiple residues affects people's health. When plants or soil are treated with a range of different pesticides, this range may also show in the produce grown. At present, European food safety authorities are discussing ways to avoid multiple residues.
From the perspective of a well-balanced and healthy diet, consumption of fruit and vegetables is recommended throughout the year. As no universally valid statements can be made on regional and national differences in residue levels, consumers can scarcely influence their residue intake by buying seasonal and local produce. Consumers who wish to reduce the use of pesticides should opt for organic products. A mixture of organic and conventional produce is on offer in almost all shops and supermarkets nowadays.
Regarding fruit and vegetables, thorough washing and rinsing under running water is advisable, purely for reasons of good food hygiene. Fruit and vegetables with tougher skins should be scrubbed with a vegetable brush or microfibre cloth, to at least remove some of the surface residues on the skin. Make sure to remove the outer leaves of green salads. Consumers using the peel of citrus fruits should choose organic produce, as the label "untreated" only means that the fruit has not been surface-treated.