Influence of the northern urban environment on the biological development and health of schoolchildren

Children and adolescents living in the North are particularly vulnerable to the toxic effects of the urban environment, which directly influences their physical condition. The main reasons for this vulnerability include intensive metabolism, a high rate of metabolic processes, which makes children more sensitive to toxins compared with adults, specific features of respiration, through which pollutants such as nitrogen oxides, carbon monoxide, and phenol penetrate deeply into the lower respiratory tract, and the immaturity of self-regulatory systems. The child’s organism is in an active stage of development, while its protective systems are not yet fully capable of resisting an aggressive environment. This contributes to the chronification of diseases and delayed physical development. According to published sources, delayed physical development in children living in the North, using Yakutsk as an example, results from the combined influence of extreme climatic conditions, high levels of anthropogenic pollution, and specific biological characteristics of the child’s organism. The purpose of this study is to assess biological markers of morbidity and physiological adaptation among schoolchildren living under the extreme urban conditions of Yakutsk. The climate of Yakutsk creates an additional physiological burden that depletes the adaptive reserves of the child’s organism. A study of the physical development of Yakutsk schoolchildren showed that, although 22.8% of children were overweight, growth retardation was officially recorded in 0.9% of them, which is a direct biological indicator of the adverse effects of the above-mentioned factors. The northern climate not only slows biological processes but also places increased demands on the adaptive systems of the organism. Under these conditions, iodine deficiency becomes a critical factor, since it limits the capacity of the endocrine system to maintain metabolic homeostasis. This is confirmed by the almost complete predominance of iodine-deficiency conditions among all endocrine disorders in local children.