Polychlorinated biphenyls were initially considered completely harmless, but today they are known to cause various health problems. In the vicinity of the former chemical plant, there are still a large number of old barrels with PCB substances, which are gradually being released into the environment. in 2021, we performed tests on poultry and eggs from a village near the plant and found increased levels of PCB substances, especially in eggs. In cooperation with the Slovak Technical University in Bratislava, we are testing the ability of humic substances to retain PCB substances in the soil. And the initial results look promising.