Send to

Choose Destination
Obes Surg. 2019 Nov 13. doi: 10.1007/s11695-019-04273-w. [Epub ahead of print]

The Influence of Persistent Organic Pollutants on Thyroidal, Reproductive and Adrenal Hormones After Bariatric Surgery.

Author information

Department of Surgery, Innlandet Hospital Trust, Gjøvik, Norway.
Department of Food Safety and Infection Biology, Norwegian University of Life Sciences (NMBU), Oslo, Norway.
Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway.
Institute of Clinical Medicine, Oslo University Hospital, Oslo, Norway.
Centre for Biostatistics and Epidemiology, Section for Treatment Research, Department for Research and Education, Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway.
Department of Food Safety and Infection Biology, Norwegian University of Life Sciences (NMBU), Oslo, Norway.
Research Department, Innlandet Hospital Trust, Brumunddal, Norway.
Faculty of Health and Social Sciences, Inland Norway University of Applied Sciences, Elverum, Norway.



Persistent organic pollutants (POPs) including organochlorine pesticides, polychlorinated biphenyls (PCBs), and per- and polyfluoroalkylated substances (PFASs) are suspected endocrine disruptors.


To evaluate the associations between POPs and thyroidal, reproductive, and adrenal hormones in a study population treated with bariatric surgery.


Blood samples from a cohort of 63 participants before and 1 year after bariatric surgery were analyzed for 16 lipophilic POPs, 17 PFASs, and thyroidal, reproductive, and adrenal hormones. Participants reporting relevant medical conditions or interfering medication were excluded, and plausible confounders were corrected for in multiple regression analyses.


Free thyroxine (fT4) showed a significant decrease from preoperative to postoperative follow-up, and regression analyses demonstrated that p,p'-dichlorodiphenyldichloroethylene (p,p-DDE) was inversely associated with the ratio free triiodothyronine/free thyroxine (fT3/fT4). Testosterone concentrations in male participants increased significantly in the study period, and sex hormone-binding globulin (SHBG) increased in both gender. Regression analyses showed positive associations between increased levels of lipophilic POPs and the raised postoperative testosterone and SHBG concentrations in males. For females, an inverse association between the sum perfluoroalkyl carboxylic acids (ΣPFCA) and SHBG was seen. Regression analyses of postoperative serum cortisol concentrations on changes in hexachlorobenzene (HCB) showed a non-significant inverse association.


The results suggest that POPs may have an influence on the hypothalamic-pituitary-thyroid (HPT) and the hypothalamic-pituitary-gonadal (HPG) axes after bariatric surgery. Because of small sample sizes and discrepancy in the sampling time points pre- and postoperatively, the observed hormonal impacts of POPs must be interpreted as associative and not causative. Further studies are needed to confirm the findings.


Bariatric surgery; Cortisol; Endocrine disrupting chemicals; Obesity; Reproductive hormones; Thyroid hormones


Supplemental Content

Full text links

Icon for Springer
Loading ...
Support Center