Environmental hazards posed by unintentional and excessive penetration of chemical substances into water, air and soil is noticeable in its harmful effects on plants, free range animals, quality of environment components and biodiversity in general. The chemicals used in agricultural practices enter the food chain most frequently through their application to soil or crops. Regarding the employment of pest-control preparations, rodenticides play an important role in controlling harmful rodents. The present paper reports the investigation of residues fromKumatox Z rodenticide preparation with an active ingredient – warfarin – applied to cereal crops. Kumatox Z is a rodenticide bait containing the active ingredient warfarin in 0.05% concentration. The preparation was employed in the form of cereal baits to soil surface. The research results showed the presence of warfarin residues in the treated soil and cereals grown over there. Determination of residues was carried out by HPLC; interestingly, they were found in the soil even after three years.