Partitioning of Persistent Organic Pollutants between Adipose Tissue and Serum in Human Studies

Abstract

Blood is the most widely used matrix for biomonitoring of persistent organic pollutants (POPs). It is assumed that POPs are homogenously distributed within body lipids at steady state; however, the variability underlying the partitioning of POPs between fat compartments is poorly understood. Hence, the objective of this study was to review the state of the science about the relationships of POPs between adipose tissue and serum in humans. We conducted a narrative literature review of human observational studies reporting concentrations of POPs in paired samples of adipose tissue with other lipid-based compartments (e.g., serum lipids). The searches were conducted in SCOPUS and PUBMED. A meta-regression was performed to identify factors responsible for variability. All included studies reported high variability in the partition coefficients of POPs, mainly between adipose tissue and serum. The number of halogen atoms was the physicochemical variable most strongly and positively associated with the partition ratios, whereas body mass index was the main biological factor positively and significantly associated. To conclude, although this study provides a better understanding of partitioning of POPs to refine physiologically based pharmacokinetic and epidemiological models, further research is still needed to determine other key factors involved in the partitioning of POPs.

Exposure to 4,4′‐DDE in visceral adipose tissue and weight loss in adolescents from the Teen‐LABS cohort

“…plasma, which makes it a preferred matrix for long-term exposure assessment [26,27]. Furthermore, among patients after bariatric surgery, vAT was metabolically active and underwent substantial lipolysis [28].…”

“…Most studies have focused on exposure levels in plasma or subcutaneous adipose tissue as opposed to directly in visceral adipose tissue (vAT) [22, 24, 25]. However, POPs have been shown to accumulate in vAT at higher levels than in serum or plasma, which makes it a preferred matrix for long‐term exposure assessment [26, 27]. Furthermore, among patients after bariatric surgery, vAT was metabolically active and underwent substantial lipolysis [28].…”

Sex, Nutrition, and NAFLD: Relevance of Environmental Pollution

“…It has been estimated that over 90% of human exposure to POPs released into the environment occurs through the consumption of contaminated food [ 39 ]. Given their lipophilic nature, POPs can be accumulated especially in the adipose tissue [ 40 , 41 , 42 , 43 ], and can be sequestrated in the liver [ 44 ], thus leading to metabolic dysfunctions.…”

“…It has been estimated that over 90% of human exposure to POPs released into the environment occurs through the consumption of contaminated food [39]. Given their lipophilic nature, POPs can be accumulated especially in the adipose tissue [40][41][42][43], and can be sequestrated in the liver [44], thus leading to metabolic dysfunctions. Several POPs, including industrial chemicals such as PCBs, plasticizers including phthalates and bisphenol A (BPA), and agricultural pesticides act as EDCs by interfering with hormone signaling and endocrine functions [45,46].…”

Editorial for the Special Issue on “Human Biomonitoring in Health Risk Assessment: Current Practices and Recommendations for the Future”

“…However, other biological matrices may be of some interest as they may constitute a better proxy for systemic exposure. In their review, Moriceau et al (2023) [ 2 ] compared the serum/adipose tissue ratio for persistent organic pollutants (POPs) and sought to identify key factors that could explain why for some compounds the ratio differed from 1. All included studies reported high variability in the partition coefficients of POPs and the authors concluded that further research is still needed to better investigate the partitioning of POPs.…”