There was performed a comparative analysis of the dynamics of newly diagnosed and the overall morbidity of children's population of the Republic of Tatarstan (RT) and the city of Kazan of main classes of diseases for 2004- 2012 according to the statistical reporting form N12. As an assessment of the possible impact of environmental factors on the formation of separate groups of diseases and changes in the systems of the body there was used health risk assessment according to annual average concentrations of chemicals in the ambient air Average annual indices of prevalence for the most of classes of diseases in children (0-14 years) of the population of the Republic of Tatarstan (RT) and the city of Kazan 2004-2012 (per 1000 children) showed significant differences for most classes of diseases and their rise in children of the city. Results of the assessment of the non-carcinogenic risk based on evolutionary models determined the magnitude of additional risks for the respiratory system. Non-carcinogenic health risk is assessed before the age of 19 years as negligible, until the age of 36 years as a moderate, until the age of 45 years as highfor persons over 46 years as very high.