Morphostructural Analysis of PAH-Rich Human Adipose Tissue: A Potential Silent Sequestration Site

Polycyclic aromatic hydrocarbons (PAHs) are widespread, persistent pollutants that can be sequestered within human adipose tissue due to their lipophilic nature. While this accumulation poses toxicological risks depending on dose and individual susceptibility, the specific morphological impact of chronic PAH storage on tissue architecture remains poorly defined. Here, we performed a histopathological and morphometric analysis on human subcutaneous adipose tissue samples characterized by high pyrene levels. We evaluated tissue organization, collagen distribution, the presence of inflammatory, neural, and vascular alterations and adipocyte morphometry to assess the structural response to PAH sequestration. Despite high pyrene concentrations, PAH-positive tissues maintained preserved overall architecture with normal collagen distribution, absence of lymphocytic infiltration, low macrophages, unaltered nerve fiber patterns, without evidence of vascular remodeling. Morphometry revealed smaller adipocyte area in PAH-positive samples, although not statistically significant. Our experimental data indicate that high PAH accumulation does not necessarily induce subcutaneous adipose tissue remodeling, suggesting that biochemical or metabolic alterations might occur even in the absence of evident histological changes. Further studies, with a broadened cohort, are needed to define the threshold at which PAHs' presence translates into permanent tissue damage.