Exposure to micro- and nanoplastics (MNP) is linked to sensitization profiles in children

Introduction: MNPs, derived from plastic waste due to physical or chemical degradation are ubiquitous and may pose significant health hazards. These health risks include direct toxic and indirect effects, as MNPs are commonly associated with other biotic and abiotic agents (heavy metals, chemicals and microorganisms), which makes them even more harmful. However, knowledge on their presence and potentially harmful effects on human health and allergy are still limited. The Horizon2020 Imptox project focuses on the health effects of MNPs, primarily on the develeopment and clinical manifestation of allergic diseas in the most vulnerable population- children. The aim of the study was to identify the complex relationship between environmental exposure MNP and IgE mediated allergic response and sensitization profiles to different allergens. Methods: A total of 1156 pediatric participants aged 6-18 years in Croatia were recruited to this observational study. All participants underwent skin prick testing to a standard palette of aeroallergens and food allergens (prick-to-prick method). Participants (their caregivers) also filled out questionnaires on the child`s medical history (personal and family) and assessment of exposure to MNP, as well as the frequency of food consumption (FFQ). Results: Logistic regression analysis results show that exposure to MNP (assessed by food consumption frequency and data on dermal and inhalation route of exposure) affects total sensitization rates and polysensitization rates to food and inhaled allergens (cumulative p< 0.001,c2= 26.91 and p< 0.001,c2= 26.68, respectively, N= 670). Additionally, specific sensitization profiles were linked with consumption of foods known for higher average content of MNPs- small blue fish and sensitization to inhaled allergens (c2= 17.064, p= 0.029), total sensitization rates and consumption of freshwater fish (c2= 14.294, p= 0.046), and consumption of semi-hard and hard cheeses and total sensitization and polysensitization rates to inhlaed and food allergens (c2= 17.387, p= 0.026 and c2= 19.085, p= 0.014, respectively). Conclusion: The results of this study suggest that the risk of exposure to MNPs may act in a cumulative manner of a sum of different sources (ingestion, dermal and inhalation route) and routes of exposure on allergic sensitization patterns in the pediatric population.