The goal of the investigation was to detect and assess the specific features of abnormal biochemical and immunological parameters in children living in the industrially developed areas in order to solve the tasks of early diagnosis and to enhance the efficiency of prevention of the chronic pattern of gastroduodenal diseases. It was found that children with increased contamination of biological media had more active inflammatory reactions with a trend towards the chronic pattern of an inflammatory process, altered antioxidant defense and a more common chronic inflammatory process in the biliary tract, and more significant cytolysis syndrome with gallbladder concentration dysfunction.