This study aimed to develop a near-infrared (NIR) spectroscopy method as an auxiliary tool for the rapid determination of active ingredient content (lercanidipine hydrochloride) and drug dissolution of lercanidipine hydrochloride tablets. NIR spectra of 96 batches were collected in the range of 4000-10000 cm-1. Spectral preprocessing methods were compared, and second derivative (SD) was identified as the optimal pretreatment for both content (r (correlation coefficient) = 0.8503, RMSEC (root mean square error of calibration) = 0.996, RMSEP (root mean square error of prediction) = 1.07) and dissolution (r = 0.8356, RMSEC = 2.47, RMSEP = 3.81). Following preprocessing, feature selection algorithms were further applied. For content prediction, manual selection of spectral intervals (4000-7000 cm-1 and 7800-10000 cm-1) achieved excellent performance with a correlation coefficient (r) of 0.9096, RMSEC of 0.786, and RMSEP of 1.08. For dissolution prediction, the interval combination optimization (ICO) algorithm yielded the best results (r = 0.8952, RMSEC = 2.01, RMSEP = 3.79). The proposed NIR method provides a fast, non-destructive auxiliary approach for pharmaceutical quality assessment, with strong potential to support routine quality control of lercanidipine hydrochloride tablets.

Endosulfan, an organochlorine insecticide composed of two isomers, alpha-endosulfan (isomer I) and beta-endosulfan (isomer II), was completely banned in China in 2019. Nevertheless, its environmental persistence and human bioaccumulation remain major concerns. In this study, Taizhou, Zhejiang Province, was selected as the research area, where concentrations of endosulfan isomers were systematically measured in multiple environmental media (soil, air, indoor dust, and food) and in human serum samples collected in 2022. The results showed that the median concentration of endosulfan II in human serum (83.46 ng/g lw) was significantly higher than that of endosulfan I (37.17 ng/g lw). Selective bioaccumulation of endosulfan II in the human body through combined exposure and metabolic mechanisms. Exposure assessment indicated that food was the dominant exposure pathway; however, the contribution of dust to endosulfan II exposure (33.5%) was notably higher than that of endosulfan I (16.1%). Furthermore, molecular docking analysis revealed that endosulfan II exhibited stronger binding affinity to the Megalin protein (binding energy: 5.26 kJ/mol), but weaker binding to cytochrome P450 enzymes (- 6.32 kJ/mol), suggesting slower metabolism and delayed excretion. Overall, this study provides new molecular-level evidence for understanding the persistence of banned pesticides, contributing to improved residue management and understanded for accumulation of pollutants in the body. (c) 2026 Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Objective: Lead exposure is associated with an increased risk of stroke, but studies on the global burden of stroke attributable to lead exposure remain limited. This study evaluates the temporal and spatial trends in the disease burden of stroke and its three subtypes attributable to lead exposure in 204 countries and territories from 1990 to 2021. Methods: Data from Global Burden of Disease Study (GBD) 2021 were used to estimate annual deaths, disabilityadjusted life years (DALYs), age-standardized mortality rate (ASMR), and age-standardized DALY rate (ASDR) of stroke attributable to lead exposure. The estimated annual percentage change (EAPC) was calculated to evaluate trends from 1990 to 2021. Results: Between 1990 and 2021, the global burden of stroke attributable to lead exposure increased significantly, with deaths rising from 341,294 to 556,595 and DALYs from 8.52 million to 12.02 million. However, ASMRs declined from 9.33 to 6.65 per 100,000 population (EAPC = -1.23), and ASDRs fell from 213.99 to 139.82 per 100,000 population (EAPC = -1.51). Among subtypes, ischemic stroke (IS) contributed the most to ASMRs, whereas intracerebral hemorrhage (ICH) accounted for the highest ASDRs. Males had higher ASMRs and ASDRs than females, although females exhibited greater reduction rates. The burden was disproportionately higher in older adults, particularly those over 70 years, with IS and ICH contributing significantly. Socio-demographic and regional disparities were evident, with low- and low-middle SDI regions bearing the highest burden. Conclusion: The stroke burden attributable to lead exposure remains high, with significant variations by age, sex, region, and subtypes. Public health measures and policies are urgently needed to prevent and mitigate lead exposure globally.

This study investigates the environmental persistence and human exposure risks of Dechlorane Plus (DP) in remediated, abandoned electronic waste dismantling areas in Taizhou City, China. Based on comprehensive sampling, DP concentrations, isomer profiles, and multi-pathway exposure routes were evaluated in air (median: 26.2 pg/m3), soil (median: 12.3 ng/g dry weight), indoor dust (median: 19.4 ng/g dw), and food (median: 36.9 pg/g dw). Results revealed anti-DP as the dominant isomer across all matrices (air fanti = 0.80; soil fanti = 0.92; dust fanti = 0.89; food fanti = 0.71; serum fanti = 0.85), with dietary intake identified as the primary exposure pathway (mean: 0.75 ng/kg/day), contributing 75 % of total intake. DP levels in human serum indicated ongoing human exposure (median: 9.28 ng/g lipid weight), while fugacity modeling confirmed net atmospheric deposition (ƒƒ < 0.3), suggesting the presence of persistent external sources. Molecular docking revealed stronger binding of anti-DP to CYP2B6 (-8.10 kcal/mol vs. syn-DP's - 7.33 kcal/mol), highlighting isomer-specific metabolic processing. Despite reduced contamination post-remediation, legacy DP pose long-term risks, underscoring the need for targeted mitigation strategies in repurposed electronic waste areas.

The global obesity epidemic is increasingly linked to environmental chemical exposure, yet the role of novel brominated flame retardants (NBFRs) remains poorly understood. In this cross-ethnic study of elderly agro-pastoralists in Inner Mongolia, we compared serum NBFRs levels and metabolic biomarkers between Mongolian (n = 30) and Han (n = 47) populations. The Mongolian group, with relatively higher meat/dairy-rich diets, showed significantly higher NBFR concentrations, body mass index (BMI), and low-density lipoprotein cholesterol (LDL-C). Alarmingly, 72.7 % of participants were classified as overweight/obese, far exceeding China's national average. Serum pentabromotoluene (PBT), pentabromoethylbenzene (PBEB), and pentabromobenzyl acrylate (PBBA) showed significant positive correlations with BMI (p < 0.05). The quantile G-computation (QGC) model further revealed that PBBA exerted particularly prominent effects on BMI. Strikingly, piecewise regression revealed accelerated NBFRs accumulation in individuals with BMI≥28 (p < 0.05), indicating a bidirectional “NBFRs-BMI feedback loop”. Molecular docking studies demonstrated that PBBA and PBT exhibit a higher binding affinity to PPARγ than the conventional agonist Rosiglitazone, with specific interactions at key amino acid residues (ARG-288 and ILE-326) on helix H3. These findings suggest that PBBA and PBT may act as novel PPARγ agonists, potentially promoting adipogenesis and consequently leading to weight gain.

Polychlorinated biphenyls (PCBs) are persistent organic pollutants renowned for their bioaccumation and toxicity. Although PCBs production and use were banned worldwide decades ago, PCBs still pose a health risk due to their environmental persistence and unintentional production. In this report, PCB concentrations and temporal trends in serum from residents of urban areas in eastern China is investigated. The endocrine-disrupting potentials of PCBs are also investigated, particularly effects on thyroid hormone receptors. Through analysis of five years of data, results indicated that dioxin-like PCBs and congener PCB209 concentrations maintained low and had no marked temporal trends, but that the indicator PCBs and particularly PCB52, PCB153, and PCB180 concentrations increased. Furthermore, to evaluate binding of PCBs to the thyroid hormone receptor TRβ1, molecular docking simulations are performed. It is found that the PCBs of PCB28, PCB52, and PCB153 can interfere with triiodothyronine binding to TRβ1, which are comparable to the effects of the polybrominated biphenyl BB-153, a known thyroid function disruptor. What's more, the PCB180 binds to TRβ1 more strongly than that of BB-153. Our results indicated that a continuously monitoring of human exposures to PCB28, PCB52, PCB153, PCB180, and a detailed assessment of thyroid function interference is necessary.

Ambient fine particulate matter (PM2.5) remains a environmental risk factor for cardiovascular disease (CVD). However, the specific roles of PM2.5 and its chemical components in cardiovascular events and the underlying mechanisms have not been fully understood. This study aimed to unravel the associations of short-term exposure to PM2.5 and its constituents with adverse cardiovascular outcomes. A panel study of healthy retirees was conducted and a linear mixed-effects model used to examine the relationships between PM2.5, its 18 chemical components, and key cardiovascular biomarkers. Primary outcomes included blood pressure (BP), heart rate (HR), heart rate variability (HRV), interleukin (IL)-6, IL-8, high-sensitivity C-reactive protein (hs-CRP), 8-hydroxy-2'-deoxyguanosine (8-OHdG), tissue-type plasminogen activator (t-PA), platelet monocyte aggregates (PMAs), endothelin-1 (ET-1), creatine kinase (CK), and lactate dehydrogenase (LDH). In addition, stratification by gender and glutathione S-transferase theta 1 (GSTT1) polymorphism was performed. Results showed that short-term PM2.5 exposure was significantly linked to increased systolic BP (SBP), mean arterial pressure (MAP), HR, IL-6, and ET-1, along with decreases in t-PA and HRV. Metallic components (Mn, Ni, As, Se, Rb, Sr, Mo, Sb, and Cs) and ionic components (F-, NO3-, PO43-, and SO42-) were particularly associated with elevated BP and reduced HRV. Moreover, gender and GSTT1 polymorphism modified susceptibility to these cardiovascular effects. Overall, these findings suggest that short-term PM2.5 exposure induces significant cardiovascular and biochemical changes in retirees, including elevated BP, HR, systemic inflammation, endothelial dysfunction, coagulation disturbances, and reduced HRV. PM2.5 constituents and individual factors, such as gender and GSTT1 polymorphism, contribute to these effects.

Lophatherum gracile is both edible and medicinal, and quality evaluation of lophatherum gracil is necessary to ensure the clinical efficacy of lophatherum gracil. In this study, an HPLC method was established to determine the contents of eight components in lophatherum gracil, namely orientin, isoorientin, vitexin, isovitexin, kaempferol, luteolin, caffeic acid and chlorogenic acid, and it was found that chlorogenic acid, kaempferol, isovitexin, luteolin, and isoorientin were the characteristic components for the quality difference of lophatherum gracil in different origin. At the same time, the taste of lophatherum gracil was determined, and it was found that the taste was differentiated by the content of the active components. The correlation study between the taste information and the content of active components found that the taste reacted to the high or low content of active components in the herbs, and the pattern presented could be used for rapid identification of the quality of herbs. In conclusion, the present study combines the taste of herbs with the analysis of the active components content to provide new ideas and means for the evaluation of the quality of herbs and to provide reference for their clinical application.

The study revealed that the serum DPs concentrations in thyroid patients ranged from 2.45 to 141.25 ng/g lw, with the female group showing higher DPs concentrations and a higher fanti value than males. Younger participants exhibited had higher serum DPs concentrations and fanti values compared to older age groups, compared to middle-aged and elderly groups, indicating a tendency for anti-DP accumulation. In addition, the fanti value was found to be lower in patients with metastatic thyroid tumor, potentially due to an enhanced capacity to metabolize anti-DP post-metastasis. We also examined the population of patients with varying diameters. Consequently, future studies should further investigate the possible relationship between DPs and thyroid function, with an emphasis on anti-DP.

The widespread use of brominated flame retardants (BFRs), including polybrominated diphenyl ethers (PBDEs) and novel brominated flame retardants (NBFRs), poses significant environmental and health risks, yet data on their contamination in remote agro-pastoral regions remain scarce. This study systematically investigated the pollution characteristics, sources, and human exposure risks of PBDEs and NBFRs in indoor dust and human hair from 11 households in Inner Mongolian grasslands. Results revealed that PBDEs were ubiquitous in all dust samples (median ∑10PBDEs: 15.8 ng/g dw, with a 95 % confidence interval of 2.88–48.1 ng/g dw), dominated by BDE-209 (73.6–100 %), reflecting legacy Deca-BDE usage despite regulatory restrictions. NBFRs (median ∑NBFRs: 0.77 ng/g dw, 95 % CI: 0.42–1.14 ng/g dw) in dust were predominated by hexabromobenzene (HBB, 41.7 %) and pentabromobenzylacrylate (PBBA, 18.8 %). In human hair, PBDEs (median ∑10PBDEs: 6.77 ng/g dw, 95 % CI: 2.31–52 ng/g dw) showed comparable levels to urban populations, with BDE-209 contributing 71.7–99.7 %, while NBFRs (median ∑NBFRs: 0.64 ng/g dw, 95 % CI: 0.23–1.97) mirrored dust profiles (HBB: 43.4 %), suggesting dust as a likely exposure route (r = 0.575–0.699, p < 0.05). Source analysis identified Penta-/Octa-BDE degradation and industrial applications (plastics/textiles for tetrabromo-p-xylene (pTBX)-pentabromobenzene (PBBz)-pentabromotoluene (PBT); electronics for PBBA-HBB) as key contributors. Human age-dependent accumulation patterns was observed, with higher PBDEs in the elderly and increasing PBBz/PBT levels with age (r = 0.528–0.564, p < 0.05). Despite lower dust contamination than urban areas, hair-based exposure highlighted non-dust pathways (e.g., air inhalation) for low-brominated congeners. These findings underscore the persistent risks of legacy PBDEs and emerging NBFRs in remote regions, advocating for stricter lifecycle management of BFR-containing products and long-term health monitoring.

OBJECTIVE:This study aimed to investigate the association between mixed serum exposure to dechlorane plus (DPs) and novel brominated flame retardants (NBFRs) and type 2 diabetes risk, and to identify key pollutants and their mechanisms. METHODS:A case-control study included 60 type 2 diabetes patients and 57 healthy controls. Serum levels of DPs and seven NBFRs were measured using GC-MS. Weighted quantile sum (WQS) regression, quantile g-computation (QGC), and Bayesian kernel machine regression (BKMR) models were employed to assess mixture-disease associations. Molecular docking simulations evaluated interactions between key pollutants and diabetes-related proteins. RESULTS:Serum concentrations of anti-DP, syn-DP, hexabromobenzene (HBB), and pentabromobenzene (PBBz) were significantly elevated in diabetic patients. After adjusting for age, sex, and high-density lipoprotein, all models consistently showed a significant positive association between mixed DPs/NBFRs exposure and diabetes risk. Anti-DP, HBB, and PBBz were identified as major contributors. Molecular docking indicated anti-DP binds strongly to heat shock cognate protein 70 and annexin A4, while HBB exhibits high affinity for adiponectin. CONCLUSION:Mixed serum exposure to DPs and NBFRs is associated with increased type 2 diabetes risk, primarily driven by anti-DP and HBB. Potential mechanisms include disrupted calcium signaling/insulin secretion by anti-DP and suppressed adiponectin by HBB, promoting insulin resistance. This study offers new epidemiological and mechanistic insights into environmental pollutants' role in type 2 diabetes.

This study investigated polybrominated diphenyl ethers (PBDEs) exposure and health associations among elderly agro-pastoralists from the Ordos grasslands of Inner Mongolia, China. Serum samples from 77 participants (aged ≥ 64 years; 30 Mongolian, 47 Han) were analyzed for 11 PBDE congeners. Results revealed ubiquitous contamination in all serum samples, with ∑11PBDEs ranging from 0.49 to 898 ng/g lipid weight (median: 21.2 ng/g lw). BDE-209 was the dominant congener (max: 888 ng/g lw), followed by Penta-BDEs (BDE-99, -100). Ethnic disparities were significant: Mongolians exhibited higher ∑11PBDEs (median: 54.6 ng/g lw) than Han participants (median: 17.4 ng/g lw) (p < 0.05), which may be related to meat/dairy-rich diets and potential forage/pasture contamination. Sex and BMI showed no significant differences in overall PBDEs levels, though BDE-183 positively correlated with BMI in females (p < 0.05). Biochemically, Mongolians had elevated low-density lipoprotein cholesterol (LDL-C) (p < 0.05) but lower high-density lipoprotein cholesterol (HDL-C) and glucose (p < 0.05) versus Han participants. Multivariate regression identified BDE-99 as a key biomarker, inversely associated with triglycerides (TG) after adjustment for demographic covariates (age, sex, ethnicity, BMI) (β = -0.087, p < 0.05). PBDEs may contribute to shifts in inflammatory response patterns (e.g., BDE-99 linked to neutrophils; BDE-183 to monocytes) only in metabolically dysfunctional individuals (hyperglycemia/hyperlipidemia). Findings suggest that BDE-99 may serve as a potential indicator of lipid disruption and immune dysregulation, and highlight dietary exposure and metabolic health as possible modifiers of PBDE toxicity in vulnerable populations.

Dechlorane plus (DP) has been detected in a variety of environmental media and in human. Measurement of DPs in hair, urine, and house dust across different habitats allows for the assessment of short-term spatial changes in human exposure to DPs, as well as their excretion in urine. This offers a significant reference point for further research on the behavior of persistent pollutants within organisms. We measured and analyzed the concentrations of DP in the hair and urine of 32 students from a university in Beijing during school and home phases, and in indoor dust from dormitories and some home environments. The results indicated that the concentrations of DP in three types of samples were higher during the home phase compared to the school phase. We compared the fanti values and identified selective enrichment of syn-DP in hair, along with selective excretion of syn-DP in urine. Utilizing molecular docking technique, we simulated the binding effect between DP and the Megalin protein. The results demonstrated that the binding energy of anti-DP to Megalin was higher than that of syn-DP, suggesting that anti-DP has a greater propensity to bind to Megalin and be reabsorbed. This results in higher levels of syn-DP excretion in urine. Finally, we categorized students based on their participation in the organic exposure experiment and their BMI. The results indicated that the concentrations of DP in hair and urine were higher in the exposed group compared to the non-exposed group during the school year. After excluding the effect of exposure, habitat changes were more likely to affect the accumulation and excretion of DP in normal-weight students (BMI ≤ 24 kg/m2, n=28), while overweight students (BMI > 24 kg/m2, n=4) were less affected by the effect of habitat because of their higher body fat percentage and their greater ability to accumulate DP.

This study aimed to determine the concentration of 35 PBB (polybrominated biphenyls) congeners in the human serum of residents from an electronic waste (e-waste) dismantling area compared to a control area in China. Additionally, four thyroid hormones, namely FT3, FT4, TSH, and TRH, were also analyzed. The findings revealed that the total PBB concentrations (sum of the 35 PBB congeners) ranged from 47.1 to 1360 ng/g lipid in the e-waste area and 105–1980 ng/g lipid in the control area. BB-1 and BB-10 were the dominant congeners in both study areas, followed by BB-209. Compared to the e-waste dismantling area, the control area samples had a significantly higher concentration of less-brominated (Br1–3) PBBs, including the concentrations of less-brominated congeners such as BB-1, BB-4, BB-9, and BB-10, which were significantly higher than those in the e-waste dismantling area. Conversely, more-brominated hexabromobiphenyl congeners BB- 153, BB-154 and BB-155 were found in samples from the e-waste dismantling area at significantly higher concentrations than in the control area. E-waste dismantling areas have released historically produced commercial PBB products, but equally not negligible is the exposure of the general population to newly produced PBB congeners. PBB concentrations in the e-waste dismantling area samples decreased with increasing age, while they increased with increasing age in the control area samples. Furthermore, stepwise multiple regression analysis showed a significant association between BB-103 concentrations and thyroid hormone levels. In addition, BB- 103 has the potential to interfere with the binding of T3 and thyroid hormone receptors (TR). Given these findings, the research on human exposure of PBB and the relationships between the PBB and thyroid hormones should be studied further.

Benzotriazole ultraviolet absorbers (BUVs), as emerging contaminants of extensive use, especially in plastic sports fields, have aroused increasing concern due to their potential human and environmental impacts. However, BUV exposure from plastic sports field dust is still unknown. This study compared BUVs in plastic sports field dust and indoor dust for the first time. The order of the geometric mean concentrations of the total BUVs (ΣBUVs) in plastic sports field dust was indoor badminton courts (11023 ng g-1) > basketball courts (4777 ng g-1) > plastic tracks (3779 ng g-1) > synthetic turf (1920 ng g-1) > tennis courts (689 ng g-1). The geometric mean concentrations of ΣBUVs in indoor dust (1150 ng g-1) were lower than those in most plastic sports field dust. The dominant BUV was 2-hydroxy-4-(octyloxy)benzophenone (UV-531) in plastic sports field dust, while 2,2'-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-2H-benzotriazole-2-yl)phenol] (UV-360) was the dominant BUV in indoor dust. Releases from plastic track materials, sneaker soles, and friction between them might be important BUV sources in plastic track dust. The average estimated daily intakes of ΣBUVs from plastic sports field dust for general exercisers were lower than those from indoor dust, but those for exercisers with long time or professional athletes might be higher, potentially posing health risks.

Organochlorine pesticides are chlorinated hydrocarbon compounds. The production and use of organochlorine pesticides have been restricted around the world because they are persistent and toxic and able to undergo long-range transport and bioaccumulate. It is necessary to develop efficient techniques for eliminating organochlorine pesticides from environmental media, and we also need to better understand how these techniques operate. Understanding how organochlorine herbicides behave in various environmental settings is very crucial. We looked on the photodegradation of endosulfan (endosulfan I and II) and hexachlorobenzene (HCB), two common organochlorine insecticides. Tests were conducted with pesticides at different concentrations, dissolved in various organic solvents, and exposed to light at different wavelengths. Density Functional Theory (DFT) was employed to study solvent effects. Degradation kinetics followed first-order models. The pesticides dissolved in various organic solvents showed a decrease in their degradation rates in the following order: toluene > acetone > n-hexane. It was discovered that there was a good chance the Cl atoms on the benzene ring in HCB would be eliminated through nucleophilic processes. It was discovered that endosulfan breaks preferentially at the S=O double bond. The findings will aid in the development of strategies for successfully eliminating organochlorine pesticides from environmental media by aiding in the prediction and assessment of the photochemical behaviors of the pesticides under various environmental circumstances.

Accurate quantification of soil volatile organic compounds (VOCs) flux is crucial for assessing inhalation environmental health risks and developing region-specific remediation strategies. However, land cover significantly influences VOCs emissions from soil. This study investigated benzene, a representative VOCs, using a laboratory flux chamber and numerical simulations to evaluate its release patterns under different surface covers, including bare soil (no cover), clay brick, cement, and grass. In the experiment, gaseous benzene was collected using an adsorption tube filled with Tenax-TA adsorbent. The collected samples were subsequently analyzed using thermal desorption coupled with gas chromatography-mass spectrometry. By integrating these findings with environmental health risk assessment methodologies, we developed a tailored approach for assessing inhalation health risks at benzene-contaminated sites with varying land covers. Additionally, we conducted application studies of this method across various scenarios. The results indicate that soil benzene emissions could be reduced by using low-permeability coverings such as clay brick and cement, as well as by planting vegetation. The average fluxes of benzene through covering materials were of the order of 1.22 × 10-2, 4.37 × 10-3, 2.47 × 10-3, and 9.88 × 10-4 mg m-2·s-1 for bare soil, clay brick, grass, and cement, respectively. The application of clay brick and cement coverings on the soil surface results in more pollutants remaining in the soil in liquid and adsorbed states, making them less likely to volatilize. The inhalation carcinogenic risk (CR) values for soil benzene at an abandoned oil refinery site in Northwestern China under bare soil, brick, and cement cover are 1.3 × 10-6, 1.22 × 10-6, and 9.73 × 10-7, respectively. Low-permeability covers such as clay brick and cement reduces the inhalation CR of gaseous benzene from the surface soil, and delays the growth trend of cumulative inhalation CR.

The global presence of Dechlorane Plus (DP) in environmental and human samples highlights the need for further research into its ecological risks and health effects. This study determined DP concentrations in soil and air samples from an old electronic waste dismantling area (Fengjiang) and a new electronic waste dismantling area (Binhai) in Taizhou City, China. Both syn-DP and anti-DP isomers were found in all soil and air samples. The median concentrations of DP in soil and air were 90.5 ng/g and 48.4 pg/m3 in Fengjiang, and 6.69 ng/g and 28.8 pg/m3 in Binhai. DP were widespread in the local environment, and in general at moderate levels compared with reports from other electronic waste dismantling areas. The analysis of DP isomer profiles in different seasons and the calculation of related fugacity fraction showed that anti-DP perhaps easier than syn-DP to migrate from soil to air in summer. DP concentrations in serum of residents from Fengjiang (median 9.74 ng/g) were significantly higher than those from Huangyan (common control area, median 2.77 ng/g; p < 0.01), while the fanti value showed that Fengjiang was significantly lower than Huangyan (p < 0.05). This revealed that DP exposure levels in serum perhaps one of the crucial factors influencing fanti value. Moreover, DP concentrations in serum showed an increasing trend with increasing body mass index (BMI) or age. However, the relationship between DP and sex was not observed. The fanti values of serum samples were higher than those in soil and air samples, suggested that DP perhaps stereo-selectively absorbed into the body or stereo-selectively metabolised.

Polychlorinated naphthalenes (PCNs) have stopped being produced and used but have been detected in human serum around the world. Investigating temporal trends in PCN concentrations in human serum will improve our understanding of human exposure to PCNs and the risks posed. We determined the PCN concentrations in serum collected from 32 adults in five consecutive years (2012-2016). The total PCN concentrations in the serum samples were 0.00-5443 pg/g lipid weight. We found no significant decreases in the total PCN concentrations in human serum and even found that the concentrations of some PCN congeners (e.g., CN20) increased over time. We found differences in the PCN concentrations in serum from males and females, the CN75 concentration being significantly higher in serum from females than males, meaning CN75 poses more serious risks to females than males. We found, using molecular docking techniques, that CN75 interferes with thyroid hormone transport in vivo and that CN20 affects thyroid hormone binding to receptors. These two effects are synergistic and can cause hypothyroidism-like symptoms.