The paper shows the opportunities of using WBC formula to evaluate the adaptation status of urban and rural residents to the complex of socio-economic and environmental conditions of the region. It was found that the age of the second physiological chiasm of Oryol region’s children accounts for a period of 5–6 years, which cor- responds to the generally accepted standards. Physiological highly adaptive responses were recorded among 47.4% of adolescents, 67% of rural and 36.7% of urban residents.