Serum Concentrations Research Articles

Per and Polyfluoroalkyl Substances (PFAS) Concentrations in Serum and Drinking Water in Pregnant Women from the Greater Cincinnati HOME Study

Per and Polyfluoroalkyl Substances (PFAS) Concentrations in Serum and Drinking Water in Pregnant Women from the Greater Cincinnati HOME Study

Maternal serum concentrations of persistent organic pollutants and childhood leukemia among offspring in the Finnish Maternity Cohort

Maternal serum concentrations of persistent organic pollutants and childhood leukemia among offspring in the Finnish Maternity Cohort

Serum concentrations of per- and polyfluoroalkyl substances and risk of ovarian cancer

Serum concentrations of per- and polyfluoroalkyl substances and risk of ovarian cancer

Serum concentrations of per- and polyfluoroalkyl substances (PFAS) and risk of renal cell carcinoma: Recent findings from prospective cohorts

Serum concentrations of per- and polyfluoroalkyl substances (PFAS) and risk of renal cell carcinoma: Recent findings from prospective cohorts

Interpreting mono- and poly-SCRA intoxications from an activity-based point of view: JWH-018 equivalents in serum as a comparative measure.

Synthetic cannabinoid receptor agonists (SCRAs) are a class of synthetic drugs that mimic and greatly surpass the effect of recreational cannabis. Acute SCRA intoxications are in general difficult to assess due to the large number of compounds involved, differing widely in both chemical structure and pharmacological properties. The rapid pace of emergence of unknown SCRAs hampers on one hand the timely availability of methods for identification and quantification to confirm and estimate the extent of the SCRA intoxication. On the other hand, lack of knowledge about the harm potential of emerging SCRAs hampers adequate interpretation of serum concentrations in intoxication cases. In the present study, a novel comparative measure for SCRA intoxications was evaluated, focusing on the cannabinoid activity (versus serum concentrations), which can be measured in serum extracts with an untargeted bioassay assessing ex vivo CB1 activity. Application of this principle to a series of SCRA intoxication cases (n = 48) allowed for the determination of activity equivalents, practically entailing a conversion from different SCRA serum concentrations to a JWH-018 equivalent. This allowed for the interpretation of both mono- (n = 34) and poly-SCRA (n = 14) intoxications, based on the intrinsic potential of the present serum levels to exert cannabinoid activity (cf. pharmacological/toxicological properties). A non-distinctive toxidrome was confirmed, showing no relation to CB1 activity. The JWH-018 equivalent was partly related to the poison severity score (PSS) and causality of the clinical intoxication elicited by the SCRA. Altogether, this equivalent concept allows to comparatively and timely interpret (poly-)SCRA intoxications based on CB1 activity.

Monoclonal Antibody Delivery Using 3D Printed Biobased Hollow μNe3dle Arrays for the Treatment of Osteoporosis.

Transdermal microneedles have demonstrated promising potential as an alternative to typical drug administration routes for the treatment of various diseases. As microneedles offer lower administration burden with enhanced patient adherence and reduced ecological footprint, there is a need for further exploitation of microneedle devices. One of the main objectives of this work was to initially develop an innovative biobased photocurable resin with high biobased carbon content comprising isobornyl acrylate (IBA) and pentaerythritol tetraacrylate blends (50:50 wt/wt). The optimization of the printing and curing process resulted in μNe3dle arrays with durable mechanical properties and piercing capacity. Another objective of the work was to employ the 3D printed hollow μNe3dles for the treatment of osteoporosis in vivo. The 3D printed μNe3dle arrays were used to administer denosumab (Dmab), a monoclonal antibody, to osteoporotic mice, and the serum concentrations of critical bone minerals were monitored for six months to assess recovery. It was found that the Dmab administered by the 3D printed μNe3dles showed fast in vitro rates and induced an enhanced therapeutic effect in restoring bone-related minerals compared to subcutaneous injections. The findings of this study introduce a novel green approach with a low ecological footprint for 3D printing of biobased μNe3dles, which can be tailored to improve clinical outcomes and patient compliance for chronic diseases.

Comparison of LDL cholesterol serum concentrations in patients after acute coronary syndrome between 2018 and 2022 in Germany and Europe

Comparison of LDL cholesterol serum concentrations in patients after acute coronary syndrome between 2018 and 2022 in Germany and Europe

Emerging multisystem biomarkers in hereditary transthyretin amyloidosis: a pilot study

Hereditary transthyretin (ATTRv) amyloidosis is a rare, adult-onset, progressive, multisystemic condition caused by TTR pathogenic variants. Reliable biomarkers are needed to allow early diagnosis and to monitor disease severity and progression. We measured serum concentrations of growth differentiation factor-15 (GDF-15) and uromodulin (Umod) in ATTRv patients to evaluate correlations with standard markers of disease severity (FAP stage and PND score). Blood samples were collected from 16 patients diagnosed with ATTRv amyloidosis and a verified TTR variant and from 26 healthy controls. ATTRv patients were stratified by clinical phenotype (neurologic vs. mixed), genotype (V30M vs. non-V30M), and disease severity. We found significantly higher levels of serum GDF-15 in ATTRv patients compared with controls. Mean serum Umod levels were significantly lower in patients with ATTRv than controls. A positive correlation was found between serum Umod and estimated glomerular filtration rate (eGFR), while an inverse correlation was found with cystatin C levels. Conversely, GDF-15 showed a negative correlation with eGFR, and a direct correlation with cystatin C levels. No correlation was demonstrated between GDF-15 or Umod levels and traditional cardiac biomarkers. The results identify alteration of serum levels of GDF-15 and Umod in ATTRv amyloidosis.

The components of arginine and methylarginine metabolism are indicative of altered kidney function in intrauterine growth-restricted neonates.

Intrauterine fetal growth restriction (IUGR) affects up to 10% of all pregnancies. Severe IUGR is associated with impaired kidney development, reduced nephron endowment, and chronic kidney disease later in life. Currently, no early predictive biomarker exists for detecting altered kidney function in neonates with IUGR. Because nephrons produce key enzymes for the metabolism of arginine and methylarginine components, we quantified and compared the concentrations of arginine and methylarginine metabolites between IUGR and non-IUGR neonates to identify potential biomarkers for the early detection of altered kidney function in IUGR neonates. Seventy-one IUGR and 123 non IUGR neonates were examined. Serum and Urine samples were obtained between 30 h and 5 days of life and between 5 and 70 days of life. Serum concentrations of creatinine, urea, symmetric and asymmetric-dimethylarginine metabolites (SDGV, SDMA, ADGV, and ADMA), guanidino-2-oxo-caproic acid (GOCA), citrulline, homocitrulline, arginine, and homoarginine were quantified using LC-MS/MS and standard clinical laboratory methods. Datasets were compared by Mann-Whitney--Wilcoxon or Chi-square tests for continuous and discrete parameters. P values were corrected for multiple comparisons using the Bonferroni method. After Bonferroni correction, we found that serum creatinine, urea, SDGV, ADGV, and GOCA levels were significantly lower in neonates with IUGR. Consequently, the ratios of SDGV/SDMA, ADGV/ADMA, and GOCA/homoarginine were significantly lower in IUGR neonates. Our study suggests that arginine and methylarginine are possible early biomarkers for detecting altered kidney function in IUGR neonates.

Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA) Ameliorate Heart Failure through Reductions in Oxidative Stress: A Systematic Review and Meta-Analysis

The objectives of this study were to explore the role that eicosapentaenoic acid (EPA) and/or docosahexaenoic acid (DHA) plays in heart failure (HF), highlighting the potential connection to oxidative stress pathways. Following PRISMA guidelines, we conducted electronic searches of the literature in MEDLINE and EMBASE focusing on serum EPA and/or DHA and EPA and/or DHA supplementation in adult patients with heart failure or who had heart failure as an outcome of this study. We screened 254 studies, encompassing RCTs, observational studies, and cohort studies that examined HF outcomes in relation to either serum concentrations or dietary supplementation of EPA and/or DHA. The exclusion criteria were pediatric patients, non-HF studies, abstracts, editorials, case reports, and reviews. Eleven studies met our criteria. In meta-analyses, high serum concentrations of DHA were associated with a lower rate of heart failure with a hazard ratio of 0.74 (CI = 0.59–0.94). High serum concentrations of EPA also were associated with an overall reduction in major adverse cardiovascular events with a hazard ratio of 0.60 (CI = 0.46–0.77). EPA and DHA, or n3-PUFA administration, were associated with an increased LVEF with a mean difference of 1.55 (CI = 0.07–3.03)%. A potential explanation for these findings is the ability of EPA and DHA to inhibit pathways by which oxidative stress damages the heart or impairs cardiac systolic or diastolic function producing heart failure. Specifically, EPA may lower oxidative stress within the heart by reducing the concentration of reactive oxygen species (ROS) within cardiac tissue by (i) upregulating nuclear factor erythroid 2-related factor 2 (Nrf2), which increases the expression of antioxidant enzyme activity, including heme oxygenase-1, thioredoxin reductase 1, ferritin light chain, ferritin heavy chain, and manganese superoxide dismutase (SOD), (ii) increasing the expression of copper–zinc superoxide dismutase (MnSOD) and glutathione peroxidase, (iii) targeting Free Fatty Acid Receptor 4 (Ffar4), (iv) upregulating expression of heme-oxygenase-1, (v) lowering arachidonic acid levels, and (vi) inhibiting the RhoA/ROCK signaling pathway. DHA may lower oxidative stress within the heart by (i) reducing levels of mitochondrial-fission-related protein DRP-1(ser-63), (ii) promoting the incorporation of cardiolipin within the mitochondrial membrane, (iii) reducing myocardial fibrosis, which leads to diastolic heart failure, (iv) reducing the expression of genes such as Appa, Myh7, and Agtr1α, and (v) reducing inflammatory cytokines such as IL-6, TNF-α. In conclusion, EPA and/or DHA have the potential to improve heart failure, perhaps mediated by their ability to modulate oxidative stress.

Ceruloplasmin and Lipofuscin Serum Concentrations Are Associated with Presence of Hypertrophic Cardiomyopathy

Oxidative stress reflects an imbalance between the systemic manifestation of reactive oxygen species and cells’ ability to neutralize them by antioxidant systems. The role of oxidative stress in hypertrophic cardiomyopathy (HCM) is not fully understood. The aim of the study was to examine selected parameters of oxidative stress in patients with HCM compared to the control group. We enrolled 85 consecutive HCM patients and 97 controls without HCM. The groups were matched for sex, the body mass index, and age. Oxidative stress markers included superoxide dismutase (SOD), ceruloplasmin (CER), and lipofuscin (LPS). The median age of the HCM patients was 53 (40–63) years, and 41.2% of them were male. HCM patients, compared to the control ones, had significantly increased levels of CER and LPS. The areas under the receiver operating characteristics curves (AUC) indicated a good discriminatory power of CER (AUC 0.924, sensitivity 84%, and specificity 88%), an acceptable discriminatory power of LPS (AUC 0.740, sensitivity 66%, and specificity 72%), and poor discriminatory power of SOD (AUC 0.556, sensitivity 34%, and specificity 94%) for HCM detection. CER with good predictive strength, as well as LPS with acceptable predictive power, allows for HCM detection. The utility of SOD for HCM detection is limited.

The PerioGene North Study Uncovers Serum Proteins Related to Periodontitis.

The sequalae of periodontitis include irreversible degradation of tooth-supporting structures and circulatory spread of inflammatory mediators. However, the serum protein profile in periodontitis is not well described, which is partly attributable to the limited number of studies based on large and well-characterized periodontitis cohorts. This study aims to identify novel, circulating inflammation-related proteins associated with periodontitis within the PerioGene North case-control study, which includes 478 cases with severe periodontitis and 509 periodontally healthy controls. The serum concentrations of high-sensitivity C-reactive protein (hs-CRP) and a panel of 45 inflammation-related proteins were analyzed using targeted proteomics. A distinguishable serum protein profile was evident in periodontitis cases. The protein pattern could separate cases from controls with a sensitivity of 0.81 and specificity of 0.81 (area under the curve = 0.87). Adjusted levels for hs-CRP and 24 of the 45 proteins were different between cases and controls. High levels of hs-CRP and matrix metalloproteinase-12, and low levels of epidermal growth factor (EGF) and oxidized low-density lipoprotein receptor 1 (OLR-1) were detected among the cases. Furthermore, the levels of C-C motif chemokine-19, granulocyte colony-stimulating factor-3 (CSF-3), interleukin-7 (IL-7), and hs-CRP were significantly higher in cases with a high degree of gingival inflammation. The levels of CSF-3 and tumor necrosis factor ligand superfamily member-10 TNFSF-10 were higher in cases with many deep periodontal pockets. The PerioGene North study includes detailed clinical periodontal data and uncovers a distinct serum protein profile in periodontitis. The findings of lower EGF and OLR-1 among the cases are highlighted, as this has not been presented before. The role of EGF and OLR-1 in periodontitis pathogenesis and as possible future biomarkers should be further explored.

Matrix metalloproteinases-3 (MMP-3) serum level and genetic polymorphisms associated with rheumatoid arthritis

Introduction. MMP-3 plays a crucial role in the process of bone erosion in the pathomechanism of rheumatoid arthritis (RA). It acts by removing the outer osteoid layer, which allows the osteoclasts to tightly connect and carry out the subsequent damage to the underlying bone. MMP-3 can trigger the production of other MMPs like MMP-1, MMP-7, and MMP-9, it plays a pivotal role in the remodeling of connective tissues. Aim of the study: to assess the influence of MMP-3 serum levels and single-nucleotide polymorphisms of rs679620 in the rheumatoid arthritis patients’ group in comparison to the control group. Subjects: eighty eight samples, 45 rheumatoid arthritis patients after being referred by their treating physician for regular RA test. The remaining 43 samples all represent apparently healthy people. The present study investigated the serum concentration of MMP-3 and rs679620 SNPs in the group of patients with RA, in comparison to the control group. Results. The results indicated a significant elevation in MMP-3 levels in RA patients in comparison to healthy individuals (12.75±0.38 vs 9.69±0.37) and the findings of rs679620 SNPs appeared that the patient group has a non-significant increase in both allele frequency A and genotype frequency AA when compared to the control group (66.2 vs 52.2%; p = 0.172; OR = 1.79 and 35.3 vs 17.4%; p = 0.229; OR = 2.59), but a non-significant decrease in both allele frequency C and genotype frequency CC when compared to the control group (2.94 vs 4.4%; p = 1.0; OR = 0.67 and 2.9 vs 4.3%; p = 1.0; OR = 0.67), as well as a non-significant decrease in allele frequency G and both genotypes frequency GG and AG when compared to the control group (30.9 vs 43.5%; p = 0.233; OR = 0.58, 0.0 vs 8.7%; p = 0.159; OR = 0.12 and 61.8 vs 69.6%; p = 0.585; OR = 0.71). Patients carrying the AA and AG genotype, had significantly higher serum levels of MMP-3 compared to control (P = 0.005 and 0.004) respectively. Conclusion. Rs679620 may influence joint destruction via increase MMP-3 production.

Polycyclic aromatic hydrocarbons (PAHs) in blood serum of adults living in high and low-traffic volume areas in Malaysia: A comparative cross-sectional study

Ambient polycyclic aromatic hydrocarbons (PAHs) originate predominantly from fuel combustion of motor vehicles and have the potential to affect human health. However, there is insufficient knowledge regarding serum PAHs health risks among the Malaysian population. This study aims to compare PAH concentrations, distributions, correlations, and health risks in 202 blood serum samples drawn from residents living in high-traffic volume areas (Kuala Lumpur) and low-traffic volume areas (Hulu Langat) in Malaysia. Solid phase extraction and gas chromatography-mass spectrometry (GC-MS) were employed to extract and analyze blood serum samples. Questionnaires were distributed to obtain sociodemographic and contributing factors of serum PAHs. The mean total PAHs concentration in serum of the Kuala Lumpur group was 54.44 ng g−1 lipids, double the Hulu Langat group's concentration (25.7 ng g−1 lipids). Indeno(1,2,3-cd)pyrene (IcP) and acenaphthene (ACP) feature the most and least abundant compounds in both study groups. The mean concentrations of IcP and ACP in the Kuala Lumpur and Hulu Langat groups were 26.8 vs 12.68 and 0.27 vs 0.14 ng g−1 lipids, respectively. High-molecular-weight PAHs (HMW-PAHs) composed 85% of serum total PAHs in both groups. Significant correlations were found (i) between the individual serum PAH congeners (p < 0.01) and (ii) between serum PAHs and total lipids (p < 0.01). According to the questionnaire data, high traffic volume and outdoor hobbies were the only contributory factors that confirmed significant relationships with serum PAHs (p < 0.001). Health risk assessment was computed using benzo(a)pyrene (BaP) equivalent (BaPeq) and demonstrated that the Kuala Lumpur group has twofold greater carcinogenic risk than the Hulu Langat group (16.11 vs 7.76 ng g−1 lipids). Our study reveals that traffic volumes notably impact serum PAH levels and general health among the Malaysian population.

Ultrafast and highly sensitive detection of SARS-CoV-2 spike protein by field-effect transistor graphene-based biosensors

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), etiological agent for the coronavirus disease 2019 (COVID-19), has resulted in over 775 million global infections. Early diagnosis remains pivotal for effective epidemiological surveillance despite the availability of vaccines. Antigen-based assays are advantageous for early COVID-19 detection due to their simplicity, cost-effectiveness, and suitability for point-of-care testing (PoCT). This study introduces a graphene field-effect transistor-based biosensor designed for high sensitivity and rapid response to the SARS-CoV-2 spike protein. By functionalizing graphene with monoclonal antibodies and applying short-duration gate voltage pulses, we achieve selective detection of the viral spike protein in human serum within 100 µs and at concentrations as low as 1 fg ml−1, equivalent to 8 antigen molecules per µl of blood. Furthermore, the biosensor estimates spike protein concentrations in serum from COVID-19 patients. Our platform demonstrates potential for next-generation PoCT antigen assays, promising fast and sensitive diagnostics for COVID-19 and other infectious diseases.

Physiologically Based Pharmacokinetic Modeling of Vancomycin in Critically Ill Neonates: Assessing the Impact of Pathophysiological Changes.

Dosing vancomycin for critically ill neonates is challenging owing to substantial alterations in pharmacokinetics (PKs) caused by variability in physiology, disease, and clinical interventions. Therefore, an adequate PK model is needed to characterize these pathophysiological changes. The intent of this study was to develop a physiologically based pharmacokinetic (PBPK) model that reflects vancomycin PK and pathophysiological changes in neonates under intensive care. PK-sim software was used for PBPK modeling. An adult model (model 0) was established and verified using PK profiles from previous studies. A neonatal model (model 1) was then extrapolated from model 0 by scaling age-dependent parameters. Another neonatal model (model 2) was developed based not only on scaled age-dependent parameters but also on quantitative information on pathophysiological changes obtained via a comprehensive literature search. The predictive performances of models 1 and 2 were evaluated using a retrospectively collected dataset from neonates under intensive care (chictr.org.cn, ChiCTR1900027919), comprising 65 neonates and 92 vancomycin serum concentrations. Integrating literature-based parameter changes related to hypoalbuminemia, small-for-gestational-age, and co-medication, model 2 offered more optimized precision than model 1, as shown by a decrease in the overall mean absolute percentage error (50.6% for model 1; 37.8% for model 2). In conclusion, incorporating literature-based pathophysiological changes effectively improved PBPK modeling for critically ill neonates. Furthermore, this model allows for dosing optimization before serum concentration measurements can be obtained in clinical practice.

Low-dose quercetin at 25 mg/kg ameliorates dolutegravir-lamivudine-tenofovirdisoproxilfumarate-inducedcardio-hepato-renal toxicities in Wistar rats

Combination antiretroviral therapies (cARTs) are linked with multiple-organ system (MOS) toxicities in laboratory animals, and in humans undertaking treatment for HIV/AIDS. The ameliorative potential of low-dose quercetin following cART-associated MOS-toxicities in cardio-hepato-renal organs was evaluated in in vivo model. Oral administration of cART (Dolutegravir 50 mg, Lamivudine 300 mg and Tenofovir disoproxil fumarate 300 mg [DLT]) at 9.29 mg/kg, was challenged against low-dose quercetin 25 mg/kg body weight (bw) in Wistar rats. Group 1, the normal control (NC) received distilled water (5 mL), while groups 2 to 4 received quercetin (25 mg), DLT (9.29 mg), and DLT + quercetin (9.29 mg + 25 mg respectively), per kg bw. All administrations lasted for 14 days, and thereafter animals were humanely sacrificed after intraperitoneal anesthesia injection with 100 mg ketamine /5 mg xylazine per kg bw followed by cervical dislocation. Blood and organs were harvested for analyses using standard protocols. The serum concentrations of lipid parameters [total cholesterol, triglycerides, LDL-cholesterol, and VLDL-cholesterol], liver biomarkers (total-bilirubin, direct-bilirubin, and transaminases], and kidney biomarkers [urea and creatinine] were significantly increased (p < 0.05) while electrolytes (Na+, K+, Cl− and HCO3−) were significantly decreased (p < 0.05) in DLT group but improved in DLT + Q group. Histopathology demonstrated distorted myocytes, hepatocytes and renal tubules, fatty liver with vacuolization, dystrophied glomeruli and distorted renal interstitium in DLT group, compared with normal appearing histoarchitectural features in NC and DLT + Q groups. In conclusion, oral administration of low-dose quercetin (25 mg/kg) ameliorated cART-associated cardio-hepato-renal toxicities in rats, improving their biomarkers and histoarchitecture.

Pharmacobezoar Associated Prolonged Clinical Course in a Patient with Immediate Release Quetiapine Overdose.

Quetiapine is available in both immediate-release (IR) and extended-release (XR) formulations. Quetiapine XR overdose is known to cause delayed increase in serum quetiapine concentrations. However, it is not certain whether quetiapine IR overdose would similarly cause a delayed increase in serum quetiapine concentrations. A 57-year-old woman with depression who was taking half a tablet of 25mg quetiapine IR daily was transported to our emergency department with a complaint of disturbance of consciousness 12h after a quetiapine IR overdose. On arrival, her initial vital signs were heart rate of 116 beats per minute, blood pressure of 77/43mm Hg, and oxygen saturation of 91% under 10L oxygen administration. Whole body plain computed tomography showed a large amount of gastric hyperdense content suggesting pharmacobezoar with a volume of 71.2ml. After treatment with respiratory and circulatory support, gastric lavage was performed. Her disturbance of consciousness persisted until day 5, and she was extubated on day 7. The serum concentrations of quetiapine were 2690 ng/mL at 12h after overdose, 5940 ng/mL at 40h, and 350 ng/mL at 124h after overdose. Serum concentrations of other co-ingestions were all below lethal levels. A massive quetiapine IR overdose with pharmacobezoars can cause a delayed increase in serum quetiapine concentrations.

Assessing the diagnostic utility of serum tumor markers for lung cancer detection in patients with interstitial pneumonia.

The prevalence of lung cancer among individuals afflicted with interstitial pneumonia (IP) stands at approximately 20%. The early detection of lung cancer via chest computed tomography (CT) surveillance proves challenging in IP patients. Our investigation sought to identify a potential biomarker capable of providing early indications of the presence of lung tumors in such patients. We examined the attributes of serum tumor markers, imaging characteristics, and histological findings in individuals diagnosed with IP, both with and without concurrent lung cancer. 106 patients diagnosed with IP were included in the study, comprising 36 individuals with concurrent lung cancer and 70 patients solely diagnosed with IP. Serum concentrations of CEA and CA12-5 were notably elevated in IP patients with lung cancer, compared to those with IP alone. Logistic regression analyses revealed that, in comparison to IP patients within the first quartile of CEA levels, the relative risk of developing lung cancer associated with IP escalated by 4.0-fold, 3.1-fold, 11.0-fold, and 13.3-fold in the second, third, fourth, and fifth quartiles, respectively. Upon controlling for gender and age, statistical significance in risk was observed solely for the fourth and fifth quartiles. Receiver operating characteristic (ROC) curve analysis conducted in patients diagnosed with ILD-CA identified a CEA cutoff point of 6.9ng/mL, demonstrating sensitivities of 61.1% and specificities of 78.5%. The area under the curve was calculated as 0.7(95% CI: 0.63-0.81). The serum levels of CEA were notably elevated in IP patients with concurrent lung cancer in contrast to those who were just suffering from IP. The heightened serum CEA levels correlate with an escalated risk of cancer occurrence among IP patients, suggesting that serum CEA levels could potentially serve as an indicative marker for the presence of cancer in IP patients.

Affinity of endosulfan and HCB with human serum albumin affects serum concentrations in a general population

Endosulfan and hexachlorobenzene (HCB) were previously widely used organochlorine pesticides. Much attention has been paid to trends in human exposure to endosulfan and HCB and to the transport and distribution of endosulfan and HCB within the body. We determined endosulfan I, endosulfan II, and HCB concentrations in serum samples collected from the general population of Wuxi in Jiangsu Province (China) between 2012 and 2016. The endosulfan concentrations varied little throughout the study period, but the HCB concentrations increased. The HCB concentrations were significantly higher in serum from overweight people and smokers than in serum from normal weight people (p = 0.028) and non-smokers (p = 0.011), respectively. HCB binds to human serum albumin (HSA) and can form halogen bonds to CYS-461 and ARG-484 at site II (subdomain IIIA). Fatty acids and nicotine increase the affinity between HCB and HSA, explaining the higher HCB concentrations in serum from overweight people and smokers than normal weight people and non-smokers, respectively.