On Substantiation of Reference Blood Levels of Polycyclic Aromatic Hydrocarbonsin Children and Adolescents Based on Their Hormone Profile Criteria

Introduction: Polycyclic aromatic hydrocarbons (PAH/polyarenes) as endocrine disruptors affect the excretion of thyroid hormones. To assess endocrine disorders following PAH exposures, the blood level of thyroid-stimulating hormones is tested. Objectives: To study the relationship between blood concentrations of polycyclic aromatic hydrocarbons and the thyroid hormone level and to substantiate maximum no-effect levels of PAH in blood of children and adolescents based on their hormone profile test results. Materials and methods: In 2022–2023, comprehensive chemical and clinical laboratory blood tests for children and adolescents aged 4 to 14 years (n = 81) were conducted and ambient air samples were analyzed in the areas with and without exposures to the airborne pollutants. The relationship between blood concentrations of PAHs and hormone and antibody levels in the blood serum of children and adolescents was established using regression analysis. The maximum no-effect concentration of the marker of exposure was determined as the upper limit of the 95 % confidence interval of the exponential model. Results: In the observation area, significantly higher levels of polyarenes in ambient air and blood of children and adolescents were established exceeding those measured in the reference area by 1.7–2.8 times and 3.5–9.9 times, respectively (p ≤ 0.05). A higher blood level of thyroid-stimulating hormone (TSH) and a lower concentration of urinary iodine were determined in children from the observation group. Based on TSH level, maximum no-observed-effect blood levels of naphthalene, anthracene, and pyrene in children and adolescents were identified. Discussion: The relationship between biomarkers of exposure and effect reflect the nature of impact of individual polyarenes on thyroid function. Maximum no-effect blood levels of polyarenes in the pediatric population help assess health risks from inhalation exposures. Conclusion: Based on TSH expression criterion, maximum no-effect concentrations of polyarenes in blood of children and adolescents aged 4–14 years have been established, recommended as safety criteria under chronic exposure to polycyclic aromatic hydrocarbons.