LC-MS/MS Analysis Links Environmental Pollutants to Obesity

Obesity has become a major (and increasing) worldwide public health challenge, with growing evidence implicating environmental chemicals, especially organophosphate flame retardants (OFRs) and per- and polyfluoroalkyl substances (PFAS), as potential causes because of their ability to disrupt endocrine function and lipid metabolism. Due to data on the association between these chemical mixtures and overweight in Chinese populations (especially in industrialized regions) being scarce, a critical knowledge gap has been noticed by a team of researchers from Xuzhou Central Hospital, part of China’s Southeast University. These researchers collected data from the population in northern China, used liquid chromatography-tandem mass spectrometry (LC-MS/MS) technology to detect the expression of endocrine disrupting chemicals (EDCs) and persistent organic pollutants (POPs) in the blood, and analyzed the correlation between blood EDCs and POP levels and overweight in the Chinese population, aiming to provide a reference for clarifying the hazards associated with them. A paper based on this research was published in Diabetes, Metabolic Systems and Obesity.¹

While there are numerous causes of obesity, such as overeating, low energy expenditure, and lack of physical activity, an increasing number of researchers have begun to focus on the correlation between environmental pollution and obesity as industrialization continues to advance.^2,3 Previous research has indicated that air pollution has become one of the major threats to global health and is a significant risk factor for non-communicable diseases, and an increasing body of epidemiological research has confirmed that air pollutants such as particulate matter (PM), nitrogen oxides (NOx), ozone (O₃), and polycyclic aromatic hydrocarbons (PAHs) are closely connected with overweight and obesity.^4,5

The research team conducted a matched case-control study of 214 adults from northern China, including 107 overweight individuals (body mass index [BMI] ≥ 24 kg/m²) and 107 normal-weight controls (BMI < 24 kg/m²), pair-matched by age and sex. Using LC-MS/MS, serum concentrations of 202 environmental exposures were quantified. Multivariable logistic regression, Weighted Quantile Sum (WQS) regression, and Bayesian Kernel Machine Regression (BKMR) models were employed to assess individual and cumulative associations with overweight, adjusting for key metabolic covariates (such as blood pressure, lipids, and fasting glucose).¹

Thirteen chemicals showed significant differences between groups (|log₂ fold change| ≥ 1). Ten were elevated in the overweight group, most notably tris(2-butoxyethyl) phosphate (TBOEP; adjusted odds ratio [OR] = 2.40, 95% confidence interval [CI]: 1.79-3.33), 1,3,5-triazine-2,4,6-trione tris(2,3-dibromopropyl) ester (TBC), perfluorooctanoic acid (PFOA), and perfluorobutane sulfonic acid (PFBS). The WQS index reflecting the combined effect of these 13 chemicals was strongly associated with higher odds of overweight (OR = 2.33, 95% CI: 1.77-3.07). BKMR analysis further revealed a non-linear cumulative exposure-response relationship, with maximal risk observed at moderate exposure levels.¹

“This study,” writes the authors of the paper,¹ “provides robust epidemiological evidence that circulating levels of specific environmental pollutants-particularly TBOEP, PFOA, PFBS, and TBC-are significantly associated with increased likelihood of overweight in a northern Chinese adult population. Our findings highlight the potential contribution of complex chemical mixtures to obesity etiology in rapidly industrializing settings and underscore the need for targeted environmental health interventions.”

The researchers admit to their study having several limitations, the first of which being that is a cross-sectional study; while they have identified EDCs and POPs as risk factors for obesity, they are unable to establish a causal relationship from their findings. Furthermore, the relatively small sample size limited their ability to rule out the presence of heterogeneity among participants. In addition, the study was conducted in Xuzhou, a significant industrial city in Northern China, where dietary habits differ notably from those in Southern Chinese cities. As all samples were collected from residents of that city, the team suggests that future research should consider the geographical and dietary influences when extrapolating this study’s findings to broader populations. Finally, the researchers believe that future large-scale population studies are needed to validate their work.¹

Read More on Similar Topics
Paraben Exposure and Childhood Obesity Risk in Preschoolers: UPLC-MS/MS Insights from Recent Study

References

1. Liu, Y.; Ma, F.; Zhong, Z. et al. The Impact of High-Resolution LC-MS/MS Detected Environmental Exposures on Obesity: A Study of Cumulative Effects Through Statistical Modeling. Diabetes Metab Syndr Obes. 2026, 19, 558970. DOI: 10.2147/DMSO.S558970
2. Sharma, A. M.; Padwal, R. Obesity is a Sign - Over-Eating is a Symptom: An Aetiological Framework for the Assessment and Management of Obesity. Obesity Rev. 2010, 11, 362–370. DOI: 10.1111/j.1467-789X.2009.00689.x
3. Khalil, W. J.; Akeblersane, M.; Khan, A. S. et al. Environmental Pollution and the Risk of Developing Metabolic Disorders: Obesity and Diabetes. Int J Mol Sci. 2023, 24, 8870. DOI: 10.3390/ijms24108870
4. Wang, Y.; Yu, M.; Liu, Y. Association Between Air Pollution, Altitudes, and Overweight/Obesity in China. Front Public Health. 2025, 13, 1589201. DOI: 10.3389/fpubh.2025.1589201
5. Shi, X.; Zheng, Y.; Cui, H. et al. Exposure to Outdoor and Indoor Air Pollution and Risk of Overweight and Obesity Across Different Life Periods: A Review. Ecotoxicol Environ Saf. 2022, 242, 113893. DOI: 10.1016/j.ecoenv.2022.113893