Jolanta Wrobel

Objectives: The present study evaluated the association between plasma concentrations of selected endocrine-disrupting chemicals (EDCs)—bisphenol A (BPA), methylparaben (MeP), propylparaben (PrP), 4-nonylphenol (4-NP), 4-octylphenol (4-OP), bis(2-ethylhexyl) phthalate (DEHP), and imazalil (IMZ)—and prior coronavirus disease 2019 (COVID-19) status. Methods: Plasma EDC levels were quantified via gas chromatography–mass spectrometry in 262 voluntary blood donors (121 convalescents and 141 controls) at the Regional Centre for Transfusion Medicine in Bialystok, Poland. Results: The cohort exhibited widespread environmental exposure to all selected EDCs (BPA: 1.14 ng/mL, MeP: 1.20 ng/mL, PrP: 1.38 ng/mL, 4-NP: 1.90 ng/mL, 4-OP: 0.57 ng/mL, DEHP: 49.68 ng/mL, IMZ: 20.06 ng/mL). Convalescents had significantly higher concentrations of MeP, PrP, 4-OP, and 4-NP. Logistic regression revealed that MeP, PrP, and 4-NP were significantly associated with prior COVID-19 status, increasing infection odds by 80%, 70%, and 63%, respectively. While 4-OP was strongly associated with prior COVID-19 status (odds ratio > 300 per unit change and 1.79 per 0.1 unit change), the wide confidence interval for the unit change estimate requires cautious interpretation. Conclusions: These findings suggest a strong link between selected paraben and alkylphenol exposure and prior COVID-19 status in blood donors. Additionally, the high IMZ levels highlight the need for urgent evaluation of its safety and environmental prevalence.

Background: The aim of the study was to investigate whether red blood cell antigens (A, B, D, C^w, C, c, E, e, K, k, Jk^a, Jk^b, Fy^a, Fy^b, Le^a, Le^b, M, N, S, s, and P1) from clinically relevant blood group systems were associated with susceptibility to COVID-19. Methods: This exploratory case-control study was carried out on a group of 263 donors from the Regional Center for Transfusion Medicine, Bialystok, Poland (including 121 convalescents and 142 healthy subjects). The microplate method was applied to examine the expression of 21 antigens from eight clinically relevant systems in the donors’ red blood cells. Results: No significant correlation was found between any single blood group and susceptibility to COVID-19. For a more detailed analysis, we adopted an approach involving 3-, 4- and 5-element mutual combinations of antigens. In this exploratory analysis of multi-antigen combinations, nominal statistical significance was found for a number of associations, but none remained statistically significant after adjustment for multiple testing. In the case of three-antigen associations, the strongest association was observed for cc combined with Ee and kk, with the effect size showing approximately 4× higher odds of COVID-19 (OR = 4.49, p = 0.020); in the case of four-antigen combinations, the strongest association was found for RhD(+) combined with kk, Fy^b and P1(−), as well as RhD(+) combined with cc, Ee and kk, also indicating 4× higher odds of COVID-19 (OR = 4.49 p = 0.016). For five-antigen combinations, the strongest association was observed for blood type O combined with kk, Le^b, P1(+) and MM, with the association strength reaching an OR = 4.44, p = 0.025. Conclusions: The findings suggest that analyses based solely on single blood group antigens may have limited value for assessing the susceptibility to COVID-19. In contrast, combinations of red blood cell antigens may provide more reliable correlations with the susceptibility to COVID-19. However, these findings should be interpreted with caution and require confirmation on larger and more representative populations.

Neutrophils are the most numerous population of peripheral blood leukocytes and play a key role in innate immunity, participating in antibacterial, antifungal, antiviral, and antitumor responses. Their activity can be modulated by endogenous and exogenous factors, including pesticides, among which fungicides such as the commonly used imazalil (IMZ) constitute a significant group. The objective of this study was to assess the effect of IMZ (at an environmental dose of 0.07 ng/mL, as well as 10- and 100-fold higher doses) on selected functions of neutrophils. This study demonstrated that neutrophils incubated with IMZ at a dose detectable in the serum, exhibited lower phagocytotic capacity. In addition, at a 10-fold higher dose, this compound reduced the chemotactic capacity of neutrophils and led to increased activity of NADPH oxidase in these cells. Furthermore, it was observed that at the highest concentration used in this study IMZ intensified the production of nitric oxide. The exposure of neutrophils—the first line of defense—to IMZ affected their locomotion and pathogen-eliminating function. Moreover, the response of neutrophils was not proportionate to the concentration of IMZ used in the study.