Signs of Phenotypic Changes in Children Constantly Exposed to Elevated Environmental Levels of Chemical Pollutants in the City of Nizhny Tagil

Abstract

Background: Environmental epigenetics plays an important role in developing a phenotype of diseases. Objective: To identify signs of phenotypic changes in children constantly exposed to high environmental levels of chemical pollutants in the city of Nizhny Tagil. Materials and methods: The study was conducted in a specialized kindergarten for children suffering from different allergic diseases in the city of Nizhny Tagil. To detect phenotypic signs of environmental exposure, we used data on clinical diagnoses, medical history, and pediatric physical examination, as well as the results of a parent survey on allergies. We then measured blood and urinary levels of some metals and total IgE as a marker of lead poisoning in children. Results: According to clinical diagnoses, food intolerance was noted in 97.7 % of the children, 91.2 % suffered from allergic dermatitis, and almost 20 % were allergic to house dust. Phenotypic manifestations of food intolerance testified to the predominance of its skin phenotype. Every third child had symptoms of psychological disorders. The questionnaire-based survey revealed a positive allergic status in 83.1 % of the parents, mainly with skin manifestations. High blood levels of lead, nickel, cobalt, and cadmium exceeding the safe level by 23.6–240 % were observed in the study population. The syndrome of chronic xenogeneic intoxication was established in 57.3 % of cases and the syndrome of sensitization to low doses of chemicals – in 41.6 % of them. Almost 25 % of the children were underweight, which was associated with their blood cadmium levels. Conclusions: Our findings confirm the few literature data on such health effects of heavy metals in children as asthma, eczema and food allergies, as well as low body weight and height. Studies of the signs of phenotypic changes in the group of children suffering from allergies and exposed to environmental hazards are most likely to indicate the adverse impact of heavy metals on the immune system, manifestations of epigenetic mechanisms forming the allergy phenotype, which can potentially lead to transgenerational inheritance.