Pesticides are biologically active substances playing an invaluable role in crop management or controlling the population of insects, which are vectors of some diseases, for example, malaria. Unfortunately, apart from their beneficial effects, for example, the increase in food production or disease prevention, pesticides have been blamed for several unfavorable effects exerted on humans and the environment. Some pesticides have been found to be responsible for mutations and carcinogenesis [1]. Developed countries put a ban on using several groups of pesticides, organochlorine pesticides for instance, and set limits for the use of these substances in, for example, the agricultural sector [2]. However, an excessive use of pesticides in developing countries still poses a threat on a global scale as pesticides may undergo long-distance transport from their origins [3]. That is the reason for finding pesticides even in remote areas. Upon entering the environment, pesticides may be transported by flows, colloids, or nanopraticles; those that are volatile may travel long distances to condensate over areas with lower temperatures far from the pollution source [3]. Apart from transport, pesticides may be sorbed onto the surface of soil particles or undergo transformation. Therefore, there is a need to study pesticide transport and fate in the environment. A lot of studies focused only on parent pesticide compounds without taking into account the degradation products 246formed in different environment compartments, such as soil or groundwater. Studying only the level of parent compounds in the environment may even lead to a false conviction that a given pesticide is safe due to its quick elimination from the environment. However, degradation products may have greater toxicity. It is important to know the products of pesticide transformations as these may have a great impact on the environment and may be even more toxic than the parent compounds. This can be achieved, at least partially, by researching the transformation kinetics of pesticides.