[Animals] The electromagnetic fields of the high tension towers stress the bees

[Draeno]

 

The closer to a power tower, the fewer flowers. And that has to do with the bees, stressed by the electromagnetic field of the tower. This is what has been observed by a group of Chilean entomologists who have carried out a series of experiments in poppy fields and in the laboratory. The scientists found that exposure to electromagnetic fields altered the expression of bee genes related to stress and behavior. The result was that the plants near the towers produced fewer seeds, affecting their survival. This could be happening along the entire length of the line and with other key insects for pollination.

The California poppy (Eschscholzia californica) is an invasive plant native to this region of the United States and Mexico. But the beauty of its orange flowers has made it an ornamental, and it is cultivated in various areas with a Mediterranean climate. There are also those who have found a medicinal use for it. The poppy needs bees to pollinate its flowers. These insects use a sophisticated navigation system supported by magnetic receivers to find the flower fields and return to the hive. But the electromagnetic fields of the high tension towers could be interfering with this ability, short-circuiting an interaction that is basic both in nature and in agriculture.

After observing that the flowering of the plants was less around the high tension towers, Marco Molina, director of the Center for Integrative Ecology at the University of Talca (Chile) and a group of Chilean and Argentine researchers wanted to see what was happening. They suspected that there was a connection between electricity, plants and bees. To investigate it, they focused on several fields of California poppy (naturalized long ago in Chilean lands) in the town of Quinamávida. To compare the possible impact of electromagnetic fields, they located several high-voltage pylons, some of them out of use. “One of the experimental complexities is evaluating the tower effect; that is to say, how the presence of a metal structure with hundreds of meters of cable affects the visits of pollinators”, highlights Molina. That is why they studied the behavior of insects in areas with active and inactive towers.

As detailed in the scientific journal Science Advances, they measured the range and intensity of the electromagnetic field around the towers at various distances (10, 25, 20 and 200 meters and beyond). Near the inactive poles, the electromagnetic field did not reach 1.5 microteslas (the tesla is a unit of measurement for electromagnetism). Meanwhile, at 10 meters from an active tower, the intensity was 9.47 microteslas, falling by half at 50 meters and being negligible from 200 meters.

Bees use the earth's electromagnetic field in their navigation, so there is a possibility that artificial electromagnetic fields interfere with the natural one. To find out, they analyzed honey bees (Apis mellifera) that visited the different fields. They found that those that foraged closest to the active rooks produced an excess of a protein called HsP70. “We selected HsP70 because it has a widely observed functional role in insects and that it is activated by stress factors; therefore, it acts as a molecular marker for a condition of environmental stress”, explains Molina. This stress is manifested at the physiological level in an increase in temperature and in changes in the behavior of the animal.

To measure the extent of these disturbances, the scientists carried out a series of experiments in the laboratory, exposing several bees to a solenoid, a coil that generates its own electromagnetic field when an electric current is passed through it. After exposing them to a field of the same intensity as the one measured near the towers, they studied the expression of 14 genes related to the immune system or navigation. In 12 of them, they observed expression differences between exposed and unexposed bees. Regarding the HsP70 protein, the expression was 52% higher in the former than in the latter.

 

https://elpais.com/ciencia/2023-05-12/los-campos-electromagneticos-de-las-torres-de-alta-tension-estresan-a-las-abejas.html