Occurrence Patterns of Bisphenol Analogues in Human Blood, Subcutaneous Fat, and Visceral Fat

Bisphenol analogues (BPs) are well-established endocrine-disrupting chemicals (EDCs). While they are generally not classified as persistent organic pollutants due to their relatively rapid metabolism and urinary excretion, a fraction can accumulate in tissues, including the adipose. This bioaccumulation raises concerns about the potential for prolonged endocrine disruption and chronic toxicity. This study investigated the distribution and accumulation of nine BPs in human blood, visceral adipose tissue (VAT), and subcutaneous adipose tissue (SAT). By comparing the detection rates and concentrations of BPs in paired blood and adipose samples, we found that certain BPs (particularly BPF, BPE, and BPA-G) exhibit preferential accumulation in adipose tissues. The accumulation propensity was slightly higher in SAT than in VAT. Correlation analysis revealed that the sources of the same BP in VAT and SAT were highly consistent, whereas most BPs in adipose tissues had significantly different sources compared with those in blood. Further analysis suggested that age and obesity might be key factors influencing the differential accumulation of BPs in adipose tissues. Since accumulated BPs can be slowly or substantially released during lipolysis, our findings highlight that the adipose tissue reservoir of BPs may play an important role in their long-term toxic effects.