Self-assembled mesoporous silica decorated with biogenic carbon dot nanospheres hybrid nanomaterial for efficient removal of aqueous Methoxy-DDT via a Short-Bed Adsorption column technique.

Methoxy-DDT is an organochlorine pesticide extensively used in agricultural practices as a DDT substitute. Methoxy-DDT has been found and quantified in several investigations in groundwater, drinking water, sediment, and various biota. Therefore, designing efficient and cost-effective adsorbents for removing methoxy-DDT is vital. In this work, we embedded Ficus benghalensis L. derived carbon dots (CDs) in mesoporous silica (MS) to fabricate MS-CDs nanohybrid material. MS-CDs nanohybrid exhibited remarkable selectivity and removal efficiency towards methoxy-DDT, outperforming other endocrine disruptors. Parameters for industrial-scale fixed-bed adsorption columns, such as bed capacity, length, and breakthrough times, were analyzed. The kinetic study revealed that pseudo-second-order (PSO) adsorption and isotherm analysis confirmed the Langmuir model as the best fit. Small bed adsorption (SBA) column analysis was carried out using spiked Yamuna river water, and the breakthrough curves were demonstrated by varying MS-CDs bed height. The maximum adsorption capacity obtained for methoxy-DDT was 17.16 mg/g at breakthrough and 49.98 mg/g at exhaustion. The adsorbent showed 86.53% removal efficiency in the 5th cycle, demonstrating good reusability. These results indicate that the developed material MS-CDs-based organic sphere is an effective adsorbent for aqueous methoxy-DDT adsorption and can be applied to wastewater treatment.

Carbon and graphene quantum dots based architectonics for efficient aqueous decontamination by adsorption chromatography technique - Current state and prospects.

Aquatic ecosystems and potable water are being exploited and depleted due to urbanization and the encouragement of extensive industrialization, which induces the scarcity of pure water. However, current decontamination methods are limited and inefficient. Various innovative remediation strategies with novel nanomaterials have recently been demonstrated for wastewater treatment. Carbon dots (C-dots) and graphene quantum dots (GQ-dots) are the most recent frontiers in carbon nanomaterial-based adsorption studies. C-dots are extremely small (1-10 nm) quasi-spherical carbon nanoparticles (mostly sp3 hybridized carbon), whereas GQ-dots are fragments of graphene (1-20 nm) composed of primarily sp2 hybridized carbon. This article highlights the function of C-dots and GQ-dots with their specifications and characteristics for the efficient removal of organic and inorganic contaminants in water via adsorption chromatography. The alteration of adsorption attributes with the hybrid blending of these dots has been critically analyzed. Moreover, various top-down and bottom-up approaches for synthesizing C-dots and GQ-dots, which ultimately affect their morphology and structure, are described in detail. Finally, we review the research deficit in the adsorption of diverse pollutants, fabrication challenges, low molecular weight, self-agglomeration, and the future of the dots by providing research prospects and selectivity and sensitivity perspectives, the importance of post-adsorption optimization strategies and the path toward scalability at the tail of the article.

Urinary paraben exposure increases the risk of a low estimated glomerular filtration rate in Taiwanese general population.

BACKGROUND: The inconsistent relationship between chemical exposure and estimated glomerular filtration rate (eGFR) has been examined in only a few studies. We investigated the association between paraben exposure and indicators of renal function in a total of 361 individuals recruiting from a representative study. METHOD: The levels of urinary parabens, including methylparaben (MeP), ethylparaben (EtP), propylparaben (PrP), and butylparaben (BuP), were measured using UPLC-MS/MS. The association between paraben exposure and indices of renal function was assessed using multiple logistic regression and Bayesian Kernel Machine Regression (BKMR). RESULTS: The median levels of urinary parabens in the adult group were significantly higher than those in the minor group, that is, 397 vs. 148 ng/mL for MeP, 38.8 vs. 13.6 ng/mL for EtP, 117 vs. 57.7 ng/mL for PrP, and 6.61 vs. 2.79 ng/mL for BuP (all P < 0.001). In the adult group, multivariate regression models confirmed a positive association between the albumin-to-creatinine ratio and urinary MeP (ß = 0.580) and a positive association of BUN (ß = 0.061) and a negative association of eGFR (ß = -0.051) with urinary EtP (all P < 0.001). In the adult group, compared with the lowest tertile group, the adjusted odds ratio in the third tertile (T3) of urinary EtP levels indicated a 3.08 times increased risk of eGFR abnormalities, followed by the second tertile (T2) with a 2.63 times increased risk. The generalized additive model (GAM) and BKMR models showed a non-linear correlation between urinary EtP levels and early CKD, as well as reduced eGFR. We observed a significant positive cumulative effect of urinary paraben on eGFR, and a significant positive single exposure effect of urinary EtP with eGFR abnormality. CONCLUSION: We found a significant association between exposure to EtP and an increased risk of high BUN levels and decreased eGFR.

Relationship between phthalate exposure and kidney function in Taiwanese adults as determined through covariate-adjusted standardization and cumulative risk assessment.

Few studies have investigated the associations between phthalate exposure and kidney function indicators in adults by simultaneously performing covariate-adjusted creatinine standardization, cumulative risk assessment, and mixture analysis. Thus, we applied these methods simultaneously to investigate the aforementioned associations in an adult population. This cross-sectional study analyzed data (N = 839) from a community-based arm of the Taiwan Biobank. The levels of 10 urinary phthalate metabolites were measured and calculated as the sum of the molar concentrations of the dibutyl phthalate metabolite (ΣDBPm) and di(2-ethylhexyl) phthalate (DEHP) metabolite (ΣDEHPm). The hazard index (HI) and daily intake (DI) were estimated by measuring the urinary levels of the phthalate metabolite. Kidney function biomarkers were assessed by measuring the following: blood urea nitrogen (BUN), uric acid, the albumin-to-creatinine ratio (ACR), and the estimated glomerular filtration rate (eGFR). Generalized linear models were implemented to examine the associations between exposure to individual phthalates, HI scores, and kidney function biomarkers. We also employed Bayesian kernel machine regression (BKMR) to analyze the relationships between exposure to various combinations of phthalates and kidney function. ΣDEHPm levels were significantly and positively associated with BUN and ACR levels, and ΣDBPm levels were positively associated with ACR levels. In addition, eGFR was negatively associated with ΣDBPm and ΣDEHPm levels. In the BKMR model, a mixture of 10 phthalate metabolites was significantly associated with BUN, uric acid, ACR, and eGFR results. Higher DIDEHP and higher DIDnBP values were significantly associated with lower eGFRs and higher ACRs, respectively. Higher DIDiBP and DIDEP values were significantly associated with higher uric acid levels. A higher HI was significantly associated with lower eGFRs and higher ACRs. Our results suggest that exposure to environmental phthalates is associated with impaired kidney function in Taiwanese adults.

Highly electrochemically active Ti3C2Tx MXene/MWCNT nanocomposite for the simultaneous sensing of paracetamol, theophylline, and caffeine in human blood samples.

The facile fabrication is reported of highly electrochemically active Ti3C2Tx MXene/MWCNT (3D/1D)-modified screen-printed carbon electrode (SPE) for the efficient simultaneous electrochemical detection of paracetamol, theophylline, and caffeine in human blood samples. 3D/1D Ti3C2Tx MXene/MWCNT nanocomposite was synthesized using microwave irradiation and ultrasonication processes. Then, the Ti3C2Tx/MWCNT-modified SPE electrode was fabricated and thoroughly characterized towards its physicochemical and electrochemical properties using XPS, TEM, FESEM, XRD, electrochemical impedance spectroscopy, cyclic voltammetry, and differential pulse voltammetry techniques. As-constructed Ti3C2Tx-MWCNT/SPE offers excellent electrochemical sensing performance with good detection limits (0.23, 0.57, and 0.43 µM) and wide linear ranges (1.0 ~ 90.1, 2.0 ~ 62.0, and 2.0-90.9 µM) for paracetamol, caffeine, and theophylline, respectively,  in the human samples. Notably, the non-enzymatic electroactive nanocomposite-modified electrode has depicted a semicircle Nyquist plot with low charge transfer resistance (Rct∼95 Ω), leading to high ionic diffusion and facilitating an excellent electron transfer path. All the above results in efficient stability, reproducibility, repeatability, and sensitivity compared with other reported works, and thus, it claims its practical utilization in realistic clinical applications.

Rapid green analytical methodology for simultaneous monitoring of nitrosamines and semi-volatile organic compounds in water and human urine samples.

Nitrosamines and semi-volatile organic compounds (SVOCs) are carcinogenic contaminants in water and biological matrices. Conventional analytical methods often struggle to detect trace concentrations due to poor extraction efficacies. This study presents a novel, low-cost, in-syringe-assisted fast extraction cum cleanup technique coupled with GC-FID for monitoring four nitrosamines and two SVOCs in drinking water and human urine samples to measure the contamination and exposure levels. This extraction protocol combines a novel green in-syringe liquid-liquid extraction step using dimethyl carbonate as the green extraction solvent, coupled with a semi-automated solid-phase extraction cleanup process. Then, the final extractant is analyzed using gas chromatography-flame ionization detection (GC-FID) for monitoring. The method demonstrated excellent linearity (R2 > 0.998) between 1.5 and 500 ng mL⁻1 for all six target compounds. Detection limits ranged from 1.0 to 2.0 ng mL⁻1. Extraction recoveries were between 87 and 105% for both urine samples and water samples. Intra-day and inter-day precision were below 9% RSD. The blue applicability grade index evaluation scored 70.0, indicating good practical applicability. The developed analytical protocol offers a sensitive, accurate, low-cost, rapid, and environmentally friendly method for simultaneously quantifying multiple nitrosamines and SVOCs in environmental and human samples. Its performance characteristics and sustainability metrics suggest the potential for broad application in monitoring and exposure studies.

Advances in perfluoro-alkylated compounds (PFAS) detection in seafood and marine environments: A comprehensive review on analytical techniques and global regulations.

Per- and poly-fluoroalkyl substances (PFAS) are persistent organic pollutants that severely threaten the environment and human health due to their distinct chemical composition, extensive production, widespread distribution, bioaccumulation in nature, and long-term persistence. This review focuses on the occurrence and sources of PFAS in seafood, with a particular emphasis on advanced detection methods viz. nanoparticle-based, biosensor-based, and metal-organic frameworks-based, and mass spectrometric techniques. The challenges associated with these advanced detection technologies are also discussed. Recent research and regulatory updates about PFAS, including hazardous and potential health effects, epidemiological studies, and various risk assessment models, have been reviewed. In addition, the need for global monitoring programs and regulations on PFAS are critically reviewed by underscoring their crucial role in protecting human health and the environment. Further, approaches for reducing PFAS in seafood are highlighted with future innovative remediation directions. Although advanced PFAS analytical methods are available, selectivity, sample preparation, and sensitivity are still significant challenges associated with detection of PFAS in seafood matrices.  Moreover, crucial research gaps and solutions to essential concerns are critically explored in this review.

Novel fast pesticides extraction (FaPEx) strategy coupled with UHPLC-MS/MS for rapid monitoring of emerging pollutant fipronil and its metabolite in food and environmental samples.

In this work, we demonstrated a new, environmental-friendly and effective sample preparation strategy named 'in-syringe-assisted fast pesticides extraction (FaPEx)' technique coupled with LC-MS/MS for the rapid identification and monitoring of emerging pollutant fipronil and its metabolite fipronil sulfone in chicken egg and environmental soil samples. FaPEx strategy comprising of two simple steps. Firstly, the sample was placed in the syringe and extracted using low-volume acetonitrile with NaCl and anhydrous MgSO4 salts. Secondly, the extractant was passed through in-syringe-based solid-phase extraction (SPE) kit containing cleanup sorbents and salt combinations (C18, primary secondary amine, and anhydrous MgSO4) for the cleanup process. Then, the obtained clean extractant was injected into LC-MS/MS for the quantification of target analytes. Various important parameters influencing the FaPEx performances, such as solvent type, salt type, salt amount, sorbent type, and amount, were examined and optimized. The method validation results showed excellent linearity with high correlation coefficients were ≥ 0.99. The estimated LODs were between 0.05-0.07 µg/kg, and LOQs ranged between 0.1-0.25 µg/kg for target analytes in both egg and soil sample matrices, and precision values were ≤7.90%. The developed method was applied to commercial chicken egg samples and environmental soil samples analysis. Spiked recoveries ranged between 88.75-110.91% for egg samples with RSDs ≤7.42% and 82.47-107.46% for soil samples with RSDs <7.37%. These results proved that the developed sample preparation method is a simple, fast, green, low-cost, and efficient method for the analysis of fipronil and its metabolites in food and environmental samples. Thus, this method can be applied as an alternative analytical methodology in routine and standard food and environmental testing laboratories.

A low-cost eco-friendly fast drug extraction (FaDEx) technique for environmental and bio-monitoring of psychoactive drug in urban water and sports-persons' urine samples.

Nicotine is the most prominent psychoactive/addictive chemical substance consumed worldwide among young players in team sports. Moreover, urinary nicotine discharge and nicotine-based products disposal in environmental waters has been unavoidable in recent years. Therefore, sensitive monitoring of nicotine content in environmental waters and human urine samples is essential. In this study, we developed a miniaturized novel green, low-cost, sensitive, in-syringe-based semi-automated fast drug extraction (FaDEx) protocol coupled with gas chromatography-flame ionization detection (GC-FID) for the efficient environmental and bio-monitoring of nicotine in aqueous samples. The FaDEx method consists of two steps; firstly, the target analyte was extracted using dimethyl carbonate (a green solvent) and extraction salts. After that, the extraction solvent was passed automatically through the solid-phase extraction cartridge at a constant flow rate for the cleanup process to achieve the sensitive nicotine analysis by GC-FID. Under optimized experimental conditions, the developed method showed excellent linearity over the concentration ranges between 20-2000 ng mL-1 with a correlation coefficient >0.99. The detection and quantification limits were 4 and 20 ng mL-1, respectively. The presented method was applied to monitor and assess nicotine exposure in sports-persons' urine and environmental water samples. The method accuracy and precision in terms of relative recovery and relative standard deviation (for triplicate analysis) were 85.4-110.2% and ≤8%, respectively. Finally, the impact of our procedure on the environment from a green analytical chemistry view was assessed using a novel metric system called AGREE, and obtained the greenness score of 0.87, indicating its an efficient alternative green analytical protocol for routine environmental and bio-monitoring of nicotine in environmental and biological samples.

Rapid Identification and Analysis of Ochratoxin-A in Food and Agricultural Soil Samples Using a Novel Semi-Automated In-Syringe Based Fast Mycotoxin Extraction (FaMEx) Technique Coupled with UHPLC-MS/MS.

In this work, a fast mycotoxin extraction (FaMEx) technique was developed for the rapid identification and quantification of carcinogenic ochratoxin-A (OTA) in food (coffee and tea) and agricultural soil samples using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) detection. The FaMEx technique advancement is based on two plastic syringes integrated setup for rapid extraction and its subsequent controlled clean-up process. In the extraction process, a 0.25-g sample and extraction solvent were added to the first syringe barrel for the vortex-based extraction. Then, the extraction syringe was connected to a clean-up syringe (pre-packed with C18, activated carbon, and MgSO4) with a syringe filter. Afterward, the whole set-up was placed in an automated programmable mechanical set-up for controlled elution. To enhance FaMEx technology performance, the various influencing sample pretreatment parameters were optimized. Furthermore, the developed FaMEx method indicated excellent linearity (0.9998 and 0.9996 for coffee/tea and soil) with highly sensitive detection (0.30 and 0.29 ng/mL for coffee/tea and soil) and quantification limits (1.0 and 0.96 for coffee/tea and soil), which is lower than the toxicity limit compliant with the European Union regulation for OTA (5 ng/g). The method showed acceptable relative recovery (84.48 to 100.59%) with <7.34% of relative standard deviation for evaluated real samples, and the matrix effects were calculated as <-13.77% for coffee/tea and -9.7 for soil samples. The obtained results revealed that the developed semi-automated FaMEx/UHPLC-MS/MS technique is easy, fast, low-cost, sensitive, and precise for mycotoxin detection in food and environmental samples.

Facile analysis of mycotoxin in coffee and tea samples using a novel semi-automated in-syringe based fast mycotoxin extraction (FaMEx) technique coupled with direct-injection ESI-MS/MS analysis.

Identifying the risk of ochratoxin A in our daily food has become fundamental because of its toxicity. In this work, we report a novel semi-automated in-syringe-based fast mycotoxin extraction (IS-FaMEx) technique coupled with direct-injection electrospray-ionization tandem mass spectrometer (ESI-MS/MS) detection for the quantification of ochratoxin A in coffee and tea samples. Under the optimized conditions, the results reveal that the developed method's linearity was more remarkable, with a correlation coefficient of > 0.999 and > 92% extraction recovery with a precision of 6%. The detection and quantification limits for ochratoxin A were 0.2 and 0.8 ng g-1 for the developed method, respectively, which is lower than the European Union regulatory limit of toxicity for ochratoxin-A (5 ng g-1) in coffee. Furthermore, the newly developed modified IS-FaMEx-ESI-MS/MS exhibited lower signal suppression of 8% with a good green metric score of 0.64. In addition, the IS-FaMEx-ESI-MS/MS showed good extraction recovery, matrix elimination, good detection, and quantification limits with high accuracy and precision due to the fewer extraction steps with semi-automation. Therefore, the presented method can be applied as a potential methodology for the detection of mycotoxins in food products for food safety and quality control purposes. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05733-z.

Mediation effects of thyroid function in the associations between phthalate exposure and lipid metabolism in adults.

Phthalates are a group of industrial chemicals widely used in everyday products including cosmetics, food packaging and containers, plastics, and building materials. Previous studies have indicated that urinary phthalate metabolites are associated with metabolic effects including those on lipid metabolism, but the results are mixed. Furthermore, whether thyroid function mediates the association between phthalate exposure and lipid metabolism remains unclear. In the present study, we explored whether changes in thyroid function markers mediate the associations between phthalate exposure and lipid metabolism indicators in Taiwanese adults. The cross-sectional data were obtained from the Taiwan Environmental Survey for Toxicants conducted in 2013. Levels of 11 urinary phthalate metabolites, levels of 5 thyroid hormones, and 8 indicators of lipid metabolism were assessed in 222 Taiwanese adults. The relationships of urinary phthalate metabolite levels with serum thyroid hormone levels and lipid metabolism indicators were explored using multiple regression models. Mediation analysis was conducted to evaluate the role of thyroid function in the association between phthalate exposure and lipid metabolism. The metabolite of di(- 2-ethylhexyl) phthalate (∑DEHPm) exhibited a significant positive association with the lipid metabolite indicator of high-density lipoprotein cholesterol (HDL-C; ß = 0.059, 95% confidence interval [CI] = 0.009, 0.109) in adults, and the thyroid function indicator thyroxine (T4) had a significant negative association with the metabolite ∑DEHPm (ß = - 0.059, 95% CI = - 0.101, - 0.016) and a significant negative association with HDL-C (ß = - 0.284, 95% CI = - 0.440, - 0.128). The T4 indirect effect was 0.015 (95% CI = - 0.0087, 0.05), and the mediation effect was 32.2%. Our results support the assumption that exposure to phthalates influences the homeostasis of lipid metabolism by interfering with thyroid function.

Association between urinary manganese and pulmonary function in young adults: A cross-sectional design with a longitudinal cohort validation.

BACKGROUND: The impact of heavy metals on pulmonary function among young adults has been scarcely studied, especially by a longitudinal cohort study. METHODS: We prospectively enrolled 974 young adults (aged 20-45 years) during 2017-2019 and measured pulmonary function and urinary heavy metals, including manganese, copper, chromium, iron, nickel, zinc, cadmium, and lead. Among them, 461 participants had examination of the same urinary heavy metals during 2006-2008, which could be used as a cohort for long-term effect of urinary metals on pulmonary function. RESULTS: In the 974 enrolled participants, urinary heavy metals were within normal range. The urinary manganese level was the only significant factor for the observed/predicted ratios of forced vital capacity (FVC %)(ß coefficient: -1.217, p = 0.030), forced expiratory volume in one second (FEV1%)(ß: -1.664, p < 0.001), and FEV1/FVC% of predicted (ß: -0.598, p = 0.047) in multivariable linear regression under cross sectional design. In cohort analysis, the urinary manganese level was also negatively associated with the FEV1% (ß: -1.920, p = 0.021). There was no significance between other urinary heavy metals and pulmonary function for all participants. The urinary manganese significantly negatively correlated with FVC%, FEV1% and FEV1/FVC% in female subgroup whereas copper and iron were significantly negatively correlated with FVC% in male subgroup. CONCLUSIONS: Among urinary heavy metals, urinary manganese level was associated with pulmonary function negatively, even the level was within normal range. In addition, women might be more susceptible to manganese. There is emergent need to conduct further investigation to confirm the respiratory hazardous effects of manganese.

Urinary phthalate metabolites are associated with biomarkers of DNA damage and lipid peroxidation in pregnant women - Tainan Birth Cohort Study (TBCS).

Phthalate exposure and oxidative stress have been linked to adverse reproductive outcomes in experimental studies, whereas no clear line has been drawn for human, especially in pregnant women. This study explored relationships between urinary phthalate metabolites and biomarkers of lipid peroxidation and oxidative and nitrosative DNA damage. Measurements from 97 Taiwanese pregnant women were taken at three different times during second and third trimesters. Five oxidative/nitrosative stress biomarkers - 8-hydroxy-2'-deoxyguanosine (8-OHdG), 8-nitroguanine (8-NO2Gua), 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA), 8-isoprostaglandin F2α (8-isoPF2α), and malondialdehyde (MDA), and 11 phthalate metabolites were measured in urine samples. Linear regressions in each visit and linear mixed-model regressions were fitted to estimate percent changes in oxidative/nitrosative stress biomarkers resulting from inter-tertile increase of phthalate metabolite level and the cumulative concentrations of di (2-ethylhexyl) phthalate (DEHP) and dibutyl phthalate. The highest urine concentrations of phthalate metabolites and the greatest number of significant positive associations between phthalate metabolites and oxidative/nitrosative stress biomarkers were observed in the third visit and in repeated measurements analysis, respectively. Of the biomarkers related to DNA damage, 8-OHdG (25.4% inter-tertile increase for mono-iso-butyl phthalate) was more sensitive to phthalate exposure than 8-NO2Gua. Among the biomarkers of lipid peroxidation, HNE-MA (61.2% inter-tertile increase for sum of DEHP metabolites) was more sensitive than 8-isoPF2α and MDA. Our findings support the hypothesis that pregnant phthalate exposure increases the oxidative stress biomarkers of DNA damage and lipid peroxidation. Future research may elucidate the mediating roles of oxidative/nitrosative stress biomarkers in the link between phthalate exposure and adverse reproductive outcomes.

Urinary heavy metals, DNA methylation, and subclinical atherosclerosis.

PURPOSE: Lead (Pb) or cadmium (Cd) exposure has been linked to atherosclerosis. Co-exposure of these two heavy metals often occurs in humans. Recent evidence has indicated a crucial role of DNA methylation in atherosclerosis, while Pb or Cd exposure has also been shown to alter DNA methylation. However, it is still unknown whether DNA methylation plays a role in the pathological mechanism of these two heavy metals in atherosclerosis. APPROACH AND RESULTS: We enrolled 738 participants (12-30 years) to investigate the association among concentrations of urine Pb or Cd, the 5mdC/dG value (a global DNA methylation marker) and the carotid intima-media thickness (CIMT). When each heavy metal was modeled separately, the results showed urine Pb and Cd concentrations were positively associated with the 5mdC/dG value and CIMT, respectively. When the two heavy metals were analyzed in the same model, urinary Pb concentrations were positively associated with the 5mdC/dG value and CIMT, while urinary Cd concentrations were only positively associated with the CIMT. When Pb and Cd are simultaneously considered in the same logistic regression model, the odds ratios (OR) of thicker CIMT (greater than 75th percentile) with one unit increase in ln-Pb level was 1.67 (95% C.I. = 1.17-2.46, P = 0.005) when levels of 5mdC/dG were above 50th percentile, which is higher than 5mdC/dG bellow the 50th percentile (OR = 1.50 (95% C.I. = 0.96-2.35), P = 0.076). In structural equation model (SEM), Pb or Cd levels are directly associated with CIMT. Moreover, Pb or Cd had an indirect association with CIMT through the 5mdC/dG. When we considered Pb and Cd together, Pb levels had a direct association with CIMT and an indirect association with CIMT through the 5mdC/dG value, while Cd only had a direct association with CIMT. CONCLUSIONS: Our findings imply that Pb and Cd exposure might be associated with subclinical atherosclerosis, and global DNA methylation might mediate Pb-associated subclinical atherosclerosis in this young population. Future effort is necessary to elucidate the causal relationship.

Changes in insulin resistance mediate the associations between phthalate exposure and metabolic syndrome.

BACKGROUND: Information on the relationships between phthalate exposure, insulin resistance, and metabolic syndrome (MetS) in younger adults is limited. It is still unclear whether changes in insulin resistance represent an intermediate biological mechanism linking phthalate exposure and MetS. OBJECTIVE: To investigate the associations between cumulative risk of phthalates (such as daily intake [DI] and hazard index [HI]), insulin resistance, and MetS in younger adults and to examine the mediating role of insulin resistance in the associations between phthalate exposure and MetS. METHODS: Urinary phthalate metabolite levels, insulin resistance (by using the Homeostatic Model Assessment of estimated Insulin Resistance [HOMA-IR]), and MetS status were determined in 435 military personnel in Taiwan. We estimated the DI of five phthalates: dimethyl phthalate (DMP), diethyl phthalate, dibutyl phthalate, benzyl butyl phthalate (BBzP), and di (2-ethylhexyl) phthalate and the HI based on urinary phthalate metabolite levels. Cross-sectional associations between DI and HI, HOMA-IR, and the indicators of MetS were explored using logistic regression models. Mediation analysis was conducted to assess the role of insulin resistance in the associations between phthalate exposure and MetS. RESULTS: Higher DIDMP was associated with an increased odds of high HOMA-IR and MetS (odds ratio [OR], 1.686; 95% confidence interval [CI], 1.079-2.634 for high HOMA-IR; OR, 2.329; 95% CI, 1.263-4.295 for MetS). The mediation analysis indicated that 43% of the association between higher DIDMP and MetS was mediated by HOMA-IR. Higher DIBBzP and HI were associated with an increased odds of abdominal obesity (OR, 1.816; 95% CI, 1.180-2.797 for the high DIBBzP group; OR, 1.700, 95% CI, 1.105-2.614 for the high HI groups). CONCLUSIONS: Exposure to environmental phthalates may be positively associated with insulin resistance and MetS. Insulin resistance may mediate these associations between exposure to certain phthalates and MetS.

Does exposure to phthalates influence thyroid function and growth hormone homeostasis? The Taiwan Environmental Survey for Toxicants (TEST) 2013.

BACKGROUND: Previous epidemiologic and toxicological studies provide some inconsistent evidence that exposure to phthalates may affect thyroid function and growth hormone homeostasis. OBJECTIVE: To assess the relations between exposure to phthalates and indicators of thyroid function and growth hormone homeostasis disturbances both among adults and minors. METHODS: We conducted a population-based cross-sectional study of 279 Taiwanese adults (≥18 years old) and 79 minors (<18 years old) in 2013. Exposure assessment was based on urinary biomarkers, 11 phthalate metabolites measured by using online liquid chromatography/tandem mass spectrometry. Indicators of thyroid function included serum levels of thyroxine (T4), free T4, triiodothyronine, thyroid-stimulating hormone, and thyroxine-binding globulin (TBG). Growth hormone homeostasis was measured as the serum levels of insulin-like growth factor 1 (IGF-1) and insulin-like growth factor binding protein 3 (IGFBP3). We applied multivariate linear regression models to examine these associations after adjusting for covariates. RESULTS: Among adults, serum T4 levels were negatively associated with urinary mono-(2-ethyl-5-hydroxyhexyl) phthalate (ß=-0.028, P=0.043) and the sum of urinary di-(2-ethylhexyl) phthalate (DEHP) metabolite (ß=-0.045, P=0.017) levels. Free T4 levels were negatively associated with urinary mono-ethylhexyl phthalate (MEHP) (ß=-0.013, P=0.042) and mono-(2-ethyl-5-oxohexyl) phthalate (ß=-0.030, P=0.003) levels, but positively associated with urinary monoethyl phthalate (ß=0.014, P=0.037) after adjustment for age, BMI, gender, urinary creatinine levels, and TBG levels. Postive associations between urinary MEHP levels and IGF-1 levels (ß=0.033, P=0.006) were observed. Among minors, free T4 was positively associated with urinary mono benzyl phthalate levels (ß=0.044, P=0.001), and IGF-1 levels were negatively associated with the sum of urinary DEHP metabolite levels (ß=-0.166, P=0.041) after adjustment for significant covariance and IGFBP3. CONCLUSIONS: Our results are consistent with the hypothesis that exposure to phthalates influences thyroid function and growth hormone homeostasis.

Intellectual evaluation of children exposed to phthalate-tainted products after the 2011 Taiwan phthalate episode.

INTRODUCTION: Phthalate exposure may reduce intellectual development in young children. In 2011, numerous Taiwanese children had been reported to have consumed phthalate-tainted products. We investigated the effects of phthalate exposure on the intellectual development of these children after the 2011 Taiwan di-2-ethylhexyl phthalate (DEHP) episode. METHODS: We recruited 204 children, aged 3-12 y, from 3 hospitals in Taiwan between 2012 and 2013. First-morning urine samples were collected for analyzing 5 phthalate metabolites. We applied a Bayesian model to estimate the past DEHP exposure (estDEHPADD) of each participant before the 2011 DEHP episode. Demographic information, consumption of phthalate-tainted products, and maternal education, of each participant were obtained using a questionnaire. We used the Wechsler intelligence evaluation tools for assessing the children's and maternal intelligence quotient. RESULTS AND DISCUSSION: The median levels of mono-2-ethylhexyl phthalate, mono(2-ethyl-5-hydroxyhexyl) phthalate, mono(2-ethyl-5-oxohexyl) phthalate (MEOHP), mono-n-butyl phthalate, and mono-iso-butyl phthalate in the children were 9.97, 45.8, 32.2, 46.2, and 24.3µg/g creatinine, respectively. Using the aforementioned urinary phthalate metabolites, we found that the children's verbal comprehension index (N =98) was significantly negatively associated with urinary log10 MEOHP (ß, -11.92; SE, 5.33; 95%CI, -22.52~ -1.33; P=0.028) and log10 ΣDBP metabolites (ß, -10.95; SE, 4.93; 95%CI, -20.74~ -1.16; P=0.029) after adjustment for age, gender, maternal IQ and education, passive smoking, estDEHPADD, active and passive smoking during pregnancy. Through a tolerable daily intake-based approach, we only found a significant negative association between past estimate DEHPADD and VIQ≥3-<6 in preschool children whereas no correlation was observed between current DEHP exposure and IQ≥3-<6 score with/ without estimate DEHPADD adjustment. It revealed that the effect of past high-DEHP exposure on verbal-related neurodevelopment of younger child are more sensitive. CONCLUSION: Our results are consistent with the hypothesis that exposure to DEHP and DnBP affects intellectual development in preschool and school-aged children, particularly their language learning or expression ability.

Assessment of urinary thiodiglycolic acid exposure in school-aged children in the vicinity of a petrochemical complex in central Taiwan.

BACKGROUND: School-aged children living in the vicinity of vinyl chloride (VCM)/polyvinyl chloride (PVC) factories may have an increased risk of exposure to hazardous air pollutants. OBJECTIVES: We aimed to evaluate the urinary thiodiglycolic acid (TDGA) level, as TDGA is a major metabolite of VCM, for students at elementary schools near a petrochemical complex in central Taiwan. METHODS: We recruited 343 students from 5 elementary schools based on distance to the VCM/PVC factory. First-morning urine and blood samples were obtained from our subjects from October 2013 to September 2014. Urine samples were analyzed for urinary creatinine and TDGA using LC/MS-MS. Hepatitis virus infection were assessed using blood samples. We determined their vitamin consumption, resident location, parent's employment, and other demographic or lifestyle characteristics using a questionnaire. RESULTS: Median urinary TDGA levels for 316 students at 5 elementary schools from the closest (<.9km) to the farthest (∼8.6km) with respect to the petrochemical complex were 147.6, 95.5, 115.5, 86.8, and 17.3µg/g creatinine, respectively. After adjusting for age, gender, hepatitis virus infection, vitamin B consumption, passive smoking, and home to source distance, we found that urinary TDGA levels for the closest students was significantly higher than those at other schools. Further, median urinary TDGA levels for students during school time were 4.1-fold higher than those during summer vacation. CONCLUSIONS: After adjusting for confounders, urinary TDGA levels for the school-aged children decreased with increasing distances between the elementary schools and the petrochemical complex.