Plant protection products endanger our waters

Plant protection products endanger many waters

04/14/2015

Plant protection products pollute many waters worldwide. This has been shown in a study by the University of Koblenz-Landau. For years, chemicals have threatened biodiversity in streams and lakes. In Germany too, the limit values ​​are often exceeded.

Values ​​are alarmingly high worldwide
The concentration of plant protection products is often higher in many German waters than authorized by the competent authorities. Results of a study by the University of Koblenz-Landau now show that the values ​​in streams and ponds are also alarmingly high worldwide. Co-author Ralf Schulz from the Institute for Environmental Sciences explained according to a message from the news agency dpa: „It is similar in Germany as everywhere.“ There is little difference between countries with strict environmental legislation and less restrictive countries.

Danger to biodiversity
The scientists evaluated 838 studies from 73 countries for their analysis. Schulz and his colleague Sebastian Stehle present the results in the „Proceedings“ the US National Academy of Sciences („PNAS“). Schulz emphasized that there is no direct danger to people in Germany that drinking water is well monitored. The researchers collected 11,300 samples that detected toxic agents in the water for insects and small crabs. In more than 50 percent of the cases, the substances were more concentrated than allowed. According to the scientists, this endangers biodiversity. The damage has long been done in many streams and ponds, because the researchers rely on scientific articles from the years 1962 to 2012. For newer drugs, the image was reportedly more questionable than in older.

Error in application and approval of insecticides
In addition, Schulz expects a high number of unreported cases, as data from around ten percent of the world's waters is just available. In addition, insecticides are often present only in two or three days a year in the waters. That's why there are no indications on many days. „Even in highly polluted waters, insecticides are only found on a few days of the year because they are broken down very quickly or transported away in the case of running waters“, explained Schulz. „But at high concentrations, a short time is enough to kill all the insects in the water.“ Errors in the application and already in the approval of the funds could be to blame for the high values. At launch the maximum concentrations would be considered too unrealistic.

Farmers do not comply with regulations
As the agency further writes, Jörn Wogram of the Federal Environment Agency (UBA) also suspects that farmers do not comply with the provisions on the use of poisons. He also calls the findings of the investigation alarming. In this country, waters with a catchment area of ​​less than ten square kilometers would not be adequately monitored. But according to Wograms, these make up a large part of all running waters. Furthermore, especially the small brooks and ponds are closer to agricultural land and thus are particularly exposed to insecticides.

Samples are not taken specifically
The UBA is currently conducting a preliminary study to monitor smaller waters, Wogram said. According to the current planning, data could already be obtained in 2018 for the first time. Wogram also criticizes the study of large bodies of water. Samples were taken instead of targeted, only in a rigid pattern. Therefore, it can only be proven if short-term limits have been exceeded. It would be better to examine the water if farmers sprayed adjacent fields or if rains washed the fabrics off the fields.

Tens of thousands dead by pesticides
However, pesticides not only endanger biodiversity in waters, but also in other living things. A few years ago, researchers from the School of Natural Sciences at the University of Stirling (UK) found in a study that pesticides appear to play an important role in bumblebee and bee deaths. In addition, the chemicals also endanger people. Experts at the children's aid organization Terre des Hommes said years ago that around 40,000 people die each year as a result of pesticide poisoning, although it remains unclear how many of those affected are children. Symptoms such as shortness of breath, dizziness, blurred vision, eye and skin damage, muscle cramps and unconsciousness occur during acute poisoning. According to health experts, the long-term consequences of pesticide poisoning include an increased risk of allergies and cancer, impaired concentration and infertility. (Ad)