Insect remuneration on the basis of neonicinoids was once considered a miracle cure, but today it is clear how toxic they are for the environment. In 2018, the EU countries banned the use of the most important of them- Clothianidin, Thiametoxam and Imidacloprid- afterwards, after the European Food Safety Authority had also confirmed the harmfulness of fabrics for wild and honey bees.
However, the problem is far from over. Because what is considered too dangerous in the EU can obviously be expected of developing countries. The ban in the EU does not prevent exports to other regions of the world. The Swiss research platform Public Eye reported in autumn 2021 on the basis of the export documents it had viewed that exports of neonicotinoids banned in the EU with a volume of almost 3900 tonnes were registered from the EU alone from September to December 2020. This quantity is sufficient to spray the entire agricultural land in Germany, Denmark and the Benelux countries together.
The poisons are mainly exported to countries of the global South, where biodiversity is still high and whose ecosystems are therefore to be specially protected this year with the new World Nature Conservation Agreement in the fight against global species extinction.
Poisons for the developing world
Neonicotinoids were first introduced in the 1990s and are now the world's most widely used insecticides. They act systemically: the plants absorb the poison and distribute it throughout their organism. Insects then absorb it through the stems, leaves, flowers or plant juices. Once in the body, it damages as a neurotoxin in a variety of ways species against which it is not actually intended: bees, butterflies, birds, soil organisms and aquatic organisms.
The fact that harmful pesticides are now used in other world regions is also from the EU for cheap meat and fruit; This is fueling an ever greater intensification of agriculture in developing countries. And in Germany itself, the problems with neonicinoids after the far -going ban are also not over. Because even years after their use, the poisons can still be found in floors and waters of the agricultural landscape.
On the one hand, this is due to the fact that only a small part of the neonicotinoids is absorbed by the plants. Researchers estimate that in the most common form of treatment – pickling seeds with the agent before sowing – less than two percent of neonicotinoids end up in the plant. More than 98 percent of the insecticidal toxin gets into the soil. Because neonicotinoids have a half-life of more than three years, depending on the product, they accumulate in the soil. There they cause considerable damage.
Case and day
Examinations of Brazilian researchers show, for example, that the neonotinoid imidaclopride is particularly dangerous for earthworms. This group of animals places most of the animal biomass underground and is considered to be extremely significant for the flooring. Neonicotinoid concentrations that are common in the field can therefore be immediately fatal for earthworms. In addition, the worms in the study generally avoid pesticide -contaminated soils and had a lower reproductive rate in such so much than in unencumbered surfaces; Both damage the profitability.
Ants are similarly important for soil life. Researchers also found significant damage caused by neonicotinoids in them. Thus, the number of workers looking for food in experimentally contaminated colonies was significantly lower than in uncontaminated ones. In another species, even the behavior changed significantly with chronic exposure to a neonicotinoid: The animals became significantly more aggressive in confrontations with larger ant species – resulting in a 60 percent lower probability of survival.
In a review study on the effects of neonicotinoid insecticides on a wide variety of small organisms, an international team of researchers concludes that the legally compliant use of neonicotinoids already has "large-scale and far-reaching negative biological and ecological effects on a wide range of invertebrate species" on land, in water and on water soils.
So good reasons for the ban in Germany, with which the contaminated sites in the ground would also dismantle every year - there would be no exceptions to the rule. Because despite the ban on so -called emergency registrations of the Federal Office for Consumer Protection and Food Safety, neonotinoids are applied here on land and continue to burden the soil. In 2021 alone, the application was allowed to combat a sugar beet pest to around 130,000 hectares. This corresponds to an area of more than 180,000 soccer fields or the size of the Saarland.
Neonicotinoids have terrible consequences.
The history of chemical insect extermination is quite changeable: when Paul Hermann Müller was the first non-physician to receive the Nobel Prize in Medicine in 1948, the admiration for the Swiss chemist's discovery knew no bounds. Typhus had spread in war-torn Europe in the years before, and Müller had discovered that a certain chemical substance, as a contact poison, killed insects, fleas and also lice that transmitted the disease more effectively and faster than any other flying insect. "Unexpectedly and dramatically, practically out of the blue" the product appeared as a Deus ex Machina, the laudator acknowledged the discovery at the awarding of the Nobel Prize. The name of this miracle cure was: DDT.
In the following decades, DDT was sprayed worldwide in agriculture and households against any unwelcome insects, spiders and mites. It was only when the US ecologist Rachel Carson showed the devastating effects of the chemical in her book "Silent Spring" that the foundation stone was laid for the worldwide ban on insect inen poison. A ban that saved animal species such as hiking falcon and sea eagle at the last minute. Because in the enthusiasm for DDT, the devastating accompanying effects were seen: the accompanying in the body, the hormone -like effect, the egg shells of birds made it so thin that they broke under the bodies of the brooding animals - and last but not least, the probably cancer -exciting effect People.
Today a saviour – tomorrow a super poison: This is how the history of many pesticides since then can be summarized. "Because the ultimate aim is always to kill beetles, aphids, flies and other animals in the fields, new products from other classes of substances were developed and launched on the market after each ban, which were assumed not to be harmful," says Matthias Liess. "These substitutes are used until research determines after 10 or 20 years that they are also dangerous for the environment," says the ecotoxicologist from the Helmholtz Centre for Environmental Research in Leipzig. "DDT was followed by lindane, followed by parathion – the grandmother poison E 605 – and then came the neonicotinoids," says Liess.
Infected streams
The extent to which neonicotinoids are still available in the landscape after the ban also have a large scale in the landscape. For example, researchers from the University of Koblenz-Landau and the Entomological Association of Krefeld found the neonotinoid thiaclopride in insect traps during an examination of the pesticide stress of insects in 16 out of 21 examined areas throughout Germany. Particularly frightening: all examination areas were within nature reserves and the poisons were entered from a further area.
UFZ researcher Liess and his colleagues have investigated the extent of the problem in bodies of water in agricultural landscapes. The researchers analyzed pesticide contamination at more than 100 streams flowing through agricultural regions nationwide. The special thing about their approach: They did not take the samples in dry weather, but after rainfall, when pesticides are washed out into the streams. "In order to realistically depict water pollution, samples must be taken directly after rainfall," says Liess. "But that's not the weather where authorities take a water sample – it's done on a fixed schedule once a month."
Are too low water pollution levels measured nationwide because of a method error? In any case, the analyses of the samples of the UFZ researchers from twelve federal states revealed a frightening picture: the RAK limit values for pesticide concentrations (RAK = Regulatory acceptable concentration), which the approval authorities considered to be just barely acceptable, were exceeded in more than 80 percent of all water bodies. In some cases, the measured values were 100 or even almost 1000 times higher. Very noticeable here are also neonicotinoids. The RAK values for thiacloprid, for example, were exceeded by more than 100 times in four waters.
In addition to the concentration of the pollutants, the researchers looked at the ecological effects of the pesticides and found that numerous organisms react significantly more sensitively to them than previously assumed: Many water organisms are then poisoned in the factor of 10 below a number of RAK limit values. Lie's speaks of a "very unhealthy scissors for the ecosystems": "On the one hand, more is entered than is allowed, and on the other hand, the limit itself is still far too high, because there is still damage even if there are any stress." As with the concentration in the water, neonicinoids were most problematic with a view to the harmfulness for the ecosystem. They contributed almost two thirds to the total to be toxicity of all pesticides in the waters.
"Both the pollution and the limit values for pesticides in German waters are dramatically too high," concludes Liess from his study. Even with the reduction of pesticides by 50 percent by 2030 as part of the European Commission's Green Deal, he is convinced that no turnaround towards viable waters in the agricultural landscape would be feasible. The researcher has calculated that the use of pesticides in Germany would have to be reduced by 97 percent in order to achieve the goals that the Federal Government has set itself in its National Action Plan for Plant Protection Products by 2023. "De facto, this means that there could be no synthetic plant protection with pesticides without input-reducing measures such as non-pesticide-treated vegetation margins," says Liess.
Issues for society
The researcher pleads for a fundamental reform of pesticide policy. Biodiversity can only be preserved if findings from research are incorporated into the approval process of new substances much faster than before. Only through much more scientific and official monitoring of new products can the vicious circle be broken that one superpoison is followed by the next.
Ultimately, the use of the pesticide is also a social question, believes. As with road traffic or settlement construction, society must decide which level of nature use and natural damage wanted to accept. "If the goal is to kill pests, then you need more or less poison depending on the cultivation methods - the principle› Wash my fur, but don't get wet ‹either.«
Former UN Special Rapporteur Baskut Tuncak has a clear opinion on how this balancing process should end with regard to the impact of environmental pollution on human rights. "Whether they wipe out biodiversity, remain in the environment, poison workers or accumulate in breast milk, highly hazardous pesticides are not sustainable; they cannot be used safely and should have been withdrawn from circulation a long time ago," he told Global Eye.
