Occurrence of liquid crystal monomers (LCMs) in serum samples of the general population, and their association with lipid molecules

Liquid crystal monomers (LCMs), characterized by diphenyl/dicyclohexane backbones and essential for electronic displays, are increasingly detected across environmental matrices due to lifecycle release. Although the persistent, bioaccumulative, and toxic (PBT) potential of LCMs is increasingly recognized, their internal exposure and biological impacts remain insufficiently studied. This study analyzed 42 LCMs and 9 lipid species in 112 serum samples from residents of eastern China. A total of 36 LCMs were detected, with total concentrations ranging from 0.041 to 127 ng/mL (median: 10.7 ng/mL). Ten LCMs exhibited high detection frequencies (DF > 20 %), including 2O3cHdFP, 8OCB, 5MeB, 5OCB, MeP3bcH, 5CT, 2OdF3B, tFPO-CF₂-tF3T, tFMeO-2cHB, and 3dFB. Non-fluorinated LCMs were the predominant contributors to the total concentration, accounting for 67.5 % of ΣLCMs. Correlative analysis of individual LCMs suggested common exposure pathways and sources of LCMs among the residents. No statistically significant associations were observed between LCMs levels and demographic characteristics (Mann-Whitney U test, p > 0.05). Furthermore, the estimated daily intake (EDI) of ΣLCMs was determined using serum residue levels, yielding a median value of 0.44 ng/kg bw/day. Notably, concentrations of certain LCMs showed statistically significant correlations with specific lipid molecules, including docosahexaenoic acid [FA(22:6)], 18:0 phosphocholine [LysoPC(18:0)], 18:0 phosphoethanolamine [LysoPE(18:0)], D18:1–18:0 sphingomyelin [SM(d18:1/18:0)], and 18:1–18:1 diglycerol [DG(18:1/18:1)]. In summary, this study demonstrates that LCM exposure occurs in the general population and identifies significant associations between serum LCM concentrations and lipid molecular species levels. © 2026 Published by Elsevier B.V.