Characterization and distribution of polybrominated diphenyl ethers in shellfish in Shenzhen coastal waters and assessment of human health risks.

This study aims to investigate the profiles of polybrominated diphenyl ethers (PBDEs) in shellfish obtained from Shenzhen coastal waters and assess the potential health risks. We analyzed 74 shellfish samples from eight different species for PBDEs (BDE-28, -47, -99, -100, -153, -154, -183, -209). The concentrations of total PBDEs in different shellfish species ranged from 2.02 to 360.17 pg g-1 wet weight, with the highest levels found in Pectinidae, Babylonia areolate, Ostreidae, Perna viridis, Haliotis diversicolor, Corbiculidae, Pinctada margaritifera, and Veneridae in descending order. Among the PBDE congeners analyzed, BDE-47 was the most abundant, followed by BDE-154 and BDE-153. Furthermore, the estimated daily intake of PBDEs through shellfish consumption for Shenzhen residents were between 0.11 and 0.19 ng kg-1(bw) day-1. To our knowledge, this is the first study to systematically investigate the profiles of PBDEs in eight different shellfish species from Shenzhen's coastal waters and evaluate the potential human health risks associated with shellfish consumption.

Body burden and influencing factors of polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs) in male workers from a municipal waste incineration plant in China.

Emissions of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) from municipal solid waste incinerators (MSWIs) have aroused public concern around the world. However, biomonitoring evidence regarding the influence of MSWIs on the human body burden of PCDD/Fs is scarce. The aim of this study is to investigate the human body burden levels of PCDD/Fs in MSWI workers and to further explore the potential influencing factors, including duration of occupation and dietary habits, on the PCDD/F levels. A total of 98 paired serum samples from MSWI workers and non-MSWI workers were collected. Seventeen 2,3,7,8-chlorine substituted PCDD/Fs in the serums were analyzed using an isotope dilution high-resolution gas chromatograph/high-resolution mass spectrometer (HRGC/HRMS). The results showed that the mean levels of toxic equivalent (TEQ)-PCDD/Fs for the MSWI workers and the control group were 18.28 pg TEQ g-1 lipid and 5.81 pg TEQ g-1 lipid, respectively. Significantly higher concentrations of PCDD/Fs existed in the incinerator workers compared with the control subjects after adjustment of the confounding factors. OCDD was the most abundant congener in both the MSWI workers and the control subjects, accounting for 82.2% and 89.4% of the ∑17PCDD/Fs, respectively. The serum levels of PCDFs in the MSWI workers increased with the duration of occupation (ß = 0.498, P = 0.031), and a higher total concentration of PCDD/Fs were present in senior workers classified as production supervisors than routine operation staff (ß = 8.809, P = 0.008). No significant relationship was found between the PCDD/F concentrations and dietary habits. This study was the first to explore the associations between the body burden of PCDD/Fs and occupational exposure as well as dietary intake of MSWI workers in China. The findings provide scientific information for health risk assessments of human exposure to PCDD/Fs.

Chest CT imaging characteristics and their evolution of 48 patients with COVID-19 in Hengyang, China.

The novel coronavirus 2019 (2019 nCoV), appeared in Wuhan in December 2019, can cause a novel coronavirus pneumonia (Corona Virus Disease 2019, COVID-19). COVID-19 is highly infectious and easy to infect people. The epidemic has gradually spread to all parts of the country. In order to provide a basis for clinical diagnosis, this study retrospectively analyzed the imaging characteristics, evolution and related imaging manifestations of COVID-19 patients in different stages of the disease. The results suggest that the imaging findings of 48 COVID-19 patients from Hengyang, Hunan Province are comparable in different stages of the disease. Chest CT showed no pneumonia in one mild patient. Chest CT findings of moderate type (n=38) and severe type (n=9) had comparable characteristics. The main manifestations were ground-glass opacity (GGO) (18/38, 47.37%; 1/9, 11.11%), and GGO with consolidation (16/38, 42.11%; 5/9, 55.56%), which respectively presented in bilateral lungs (34/38, 89.47%; 9/9, 100.00%), and multi-lobe distribution (involving 5 lobes) (17/38, 44.74%; 8/9, 88.89%). After treatment, 28 patients were isolated for 14 days and returned to the hospital for re-examination; among them, the pulmonary lesion was completely absorbed in 15 moderate patients, while 13 patients mainly manifested as GGO. The CT imaging findings of patients with COVID-19 can detect the lesions early, observe the scope of the lesions, evaluate the severity of the lesions, and assist the clinician in completing rapid isolation, diagnosis and treatment. At the same time, it can help to understand the performance of COVID-19 in different stages and dynamically detect changes in the patient's condition.

Lipid metabolism disorders associated with dioxin exposure in a cohort of Chinese male workers revealed by a comprehensive lipidomics study.

Dioxins, environmentally stable and ubiquitous, have been found to induce metabolic changes especially in lipids and be related to multiple diseases. However, limited study is available on lipid alternations related to human exposure to dioxins. This study aims to explore the serum lipidomic characterization and to understand the underlying mechanisms of adverse health risks associated with dioxin exposure. A lipidomic study integrating nontargeted lipidomics, and targeted free fatty acid (FFA) and acyl-coenzyme A (acyl-CoA) analyses were conducted to investigate the 94 serum samples from two groups of male workers with remarkably different dioxin concentrations. The obtained results exhibited distinct lipidomic signatures between the high and low exposed groups. A total of 37 lipids were identified with the significant changes. The results revealed that dioxin exposure caused accumulations of triglyceride (TG), ceramide (Cer) and sphingoid (So), remodeling of glycerophospholipid (GP), imbalanced FFA metabolism, as well as upregulation of platelet-activating factor (PAF). These findings implied the associations between dioxin exposure and potential adverse health risks including inflammation, apoptosis, cardiovascular diseases (CVDs), and liver diseases. This study is the first to explain the associations between dioxin exposure and health effects at the level of lipid metabolism.

[Establishment the method for polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans determination in human serum].

OBJECTIVE: To establish the determination method for polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans(PCDD/Fs) in human serum, and further to provide an operable and scientific determination protocal and basis for conducting human health risk assessment for PCDD/Fs. METHODS: The serum samples were pretreated by C18 column solid phase extraction, acid silica gel column and activated carbon column purification, separated by DB-5 MS capillary column(60 m×0. 25 mm×0. 25 µm), and PCDD/Fs was quantitative analyzed by high resolution mass spectrometry. RESULTS: The method detection limit was in the range of 0. 35-3. 26 pg/g lipid. This method was further validated using international serum standard reference material sample SRM 1958. According to the reference mass fraction values given for SRM 1958, the concentrations of 17 PCDD/Fs monomers were all in the range of reference mass fraction values, and the relative standard deviation was 2%-19%(n=3). This method was further applied to determination PCDD/Fs in actual serum of human body. The result showed that the recovery rate of isotope labeled PCDD/Fs internal standards were in the range of 61%-135%. CONCLUSION: The performance of the method is highly sensitive, stable and highly accurate, which meets the requirements for the determination of PCDD/Fs in human serum and the method can be applied to human health risk assessment for PCDD/Fs in the future.

A case-control study on the association of mineral elements exposure and thyroid tumor and goiter.

Thyroid tumor and thyroid goiter are prevalent disease around the world. In this case-control study, we investigated the association between exposure to a total of twelve mineral elements and thyroid disease as well as thyroid functions. Participants with thyroid tumor or goiter (N = 197) were matched with a healthy population (N = 197) by age (± 2 years old) and same sex. Questionnaires were used to collect data about the demographic characteristics and information of subjects. Serum and urine samples were collected simultaneously for each of the subjects. Mineral elements, iodine level of urine and levels of the total seven thyroid function indexes in serum were detected respectively. Conditional logistic regression was applied to estimate the associations between mineral elements and the risk of thyroid tumor and goiter through single-element models and multiple-element models. Multiple linear regression was used to evaluate relationships between mineral elements and percentage changes of thyroid functions. Higher concentrations of mineral elements in the recruited population were found in this study than other comparable studies, and the levels of chromium (Cr), manganese (Mn), nickel (Ni), arsenic (As), cadmium (Cd), selenium (Se), antimony (Sb), thallium (Tl) and lead (Pb) in the case group were lower than the control group. According to the single-element models, Cr, Mn, Ni, Sb and Tl showed significant negative associations with the risk of thyroid tumor and goiter, and, Cd showed nonmonotonic dose response. Cd and mercury (Hg) showed a nonmonotonic percentage change with T4, while Tl was associated with the increased FT4 in the control group. Therefore, Cd, Hg and Tl may disturb the balance of thyroid function to some extent, and Cr, Mn, Ni, Cd, Sb, and Tl may become potential influencing factors for the risk of thyroid tumor and goiter.

Serum metabolic changes associated with dioxin exposure in a Chinese male cohort.

Dioxins, a group of persistent organic pollutants, have been proved to correlate with ranges of diseases by activating the aryl hydrocarbon receptor (AhR). However, previous dioxin toxicity studies primarily focused on the activation of AhR with signaling pathways at gene and protein levels. The investigation of underlying mechanisms at the metabolic level is still necessary. In this study, serum samples of 48 and 47 healthy participants with the highest and lowest dioxin levels based on quartile distribution of the serum dioxin concentrations of 215 male adults were selected for metabolomics analysis by using liquid chromatography coupled with orbitrap high-resolution mass spectrometry to investigate dioxin-related metabolic responses. The identified potential biomarkers included acylcarnitines, fatty acids and derivatives, glycerophospholipids, etc. suggested that metabolic pathways such as fatty acid ß-oxidation, essential fatty acid metabolism, arachidonic acid metabolism, glycerophospholipid and sphingolipid metabolism and purine metabolism were disturbed by dioxin exposure. The results indicated that people with high dioxin exposure levels were at the potential health risks of inflammation, liver and cardiovascular diseases. The metabolic findings may help understand the link between dioxin exposure and the diseases.

Epidemiological and clinical characteristics of COVID-19 patients in Hengyang, Hunan Province, China.

BACKGROUND: In December 2019, an ongoing outbreak of coronavirus disease 2019 (COVID-19) was first identified in Wuhan, China. The characteristics of COVID-19 patients treated in local hospitals in Wuhan are not fully representative of patients outside Wuhan. Therefore, it is highly essential to analyze the epidemiological and clinical characteristics of COVID-19 in areas outside Wuhan or Hubei Province. To date, a limited number of studies have concentrated on the epidemiological and clinical characteristics of COVID-19 patients with different genders, clinical classification, and with or without basic diseases. AIM: To study the epidemiological and clinical characteristics of COVID-19 patients in Hengyang (China) and provide a reliable reference for the prevention and control of COVID-19. METHODS: From January 16 to March 2, 2020, a total of 48 confirmed cases of COVID-19 were reported in Hengyang, and those cases were included in this study. The diagnostic criteria, clinical classification, and discharge standard related to COVID-19 were in line with the Diagnosis and Treatment Protocol for Novel Coronavirus Pneumonia (Trial Version 7) released by National Health Commission and National Administration of Traditional Chinese Medicine. The presence of SARS-CoV-2 in pharyngeal swab specimens was detected by quantitative reverse transcription polymerase chain reaction. All the data were imported into the excel worksheet and statistically analyzed by using SPSS 25.0 software. RESULTS: A total of 48 cases of COVID-19 were collected, of which 1 was mild, 38 were moderate, and 9 were severe. It was unveiled that there were 31 (64.6%) male patients and 17 (35.4%) female patients, with a female-to-male ratio of 1.82:1. The range of age of patients with COVID-19 was dominantly 30-49 years old [25 (52.1%) of 48], followed by those aged over 60 years old [11 (22.9%)]. Besides, 29.2% (14 of 48) of patients had basic diseases, and 57.2% (8 of 14) of patients with basic diseases were aged over 60 years old. The occupations of 48 COVID-19 patients were mainly farmers working in agricultural production [15 (31.5%) of 48], rural migrant workers from Hengyang to Wuhan [15 (31.5%)], and service workers operating in the service sector [8 (16.7%)]. The mean latent period was 6.86 ± 3.57 d, and the median was 7 [interquartile range (IQR): 4-9] d. The mean time from onset of symptoms to the first physician visit was 3.38 ± 2.98 (95%CI: 2.58-9.18) d, with a median of 2 (IQR: 1-5) d, and the mean time from hospital admission to confirmed diagnosis was 2.29 ± 2.11 (95%CI: 1.18-6.42) d, with a median of 2 (IQR: 1-3) d. The main symptoms were fever [43 (89.6%) of 48], cough and expectoration [41 (85.4%)], fatigue [22 (45.8%)], and chills [22 (45.8%)]. Other symptoms included poor appetite [13 (27.1%)], sore throat [9 (18.8%)], dyspnea [9 (18.8%)], diarrhea [7 (14.6%)], dizziness [5 (10.4%)], headache [5 (10.4%)], muscle pain [5 (10.4%)], nausea and vomiting [4 (8.3%)], hemoptysis [4 (8.3%)], and runny nose [1 (2.1%)]. The numbers of peripheral blood leukocytes, lymphocytes, and eosinophils were significantly reduced in the majority of the patients. The levels of C-reactive protein, fibrinogen, blood glucose, lactate dehydrogenase, D-dimer, alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase (γ-GT), myoglobin (MB), and creatine kinase (CK) were increased in 64.6%, 44.7%, 43.2%, 37.0%, 29.5%, 22.9%,20.8%, 21.6%, 13.6%, and 12.8% of patients, respectively. The incidence of ALT elevation in male patients was remarkably higher than that in females (P < 0.01), while the incidences of AST, CK, and blood glucose elevations in severe patients were remarkably higher than those in moderate patients (P < 0.05, respectively). Except for the mild patients, chest computed tomography showed characteristic pulmonary lesions. All the patients received antiviral drugs, 38 (79.2%) accepted traditional Chinese medicine, and 2 (4.2%) received treatment of human umbilical-cord mesenchymal stem cells. On March 2, 2020, 48 patients with COVID-19 were all cured and discharged. CONCLUSION: Based on our results, patients with COVID-19 often have multiple organ dysfunction or damage. The incidences of ALT elevation in males, and AST, CK, and blood glucose elevations in severe patients are remarkably higher.

Spatiotemporal variability of polybrominated diphenyl ether concentration in atmospheric fine particles in Shenzhen, China.

Polybrominated diphenyl ethers (PBDEs) are widely used as flame retardants for various products and have become ubiquitous pollutants in environmental media. However, little is known about PBDE levels in Shenzhen, a manufacturing center of electronic products. This study aimed to investigate spatiotemporal variability of PBDE concentration in atmospheric fine particles (PM2.5) and to estimate the daily inhalation exposure doses for local residents in Shenzhen, China. A total of 36 samples were collected and 8 PBDE compounds (BDE-28, 47, 99, 100, 153, 154, 183 and 209) were analyzed by isotope dilution high-resolution gas chromatograph/high-resolution mass spectrometer (HRGC/HRMS). Mean concentrations of Σ8PBDEs and BDE-209 in PM2.5 in Shenzhen were 33.47 pg/m3 and 24.75 pg/m3, respectively, which were lower than those for other reported cities from China. The mean concentration of Σ8PBDEs was higher in the winter + spring than that in summer + autumn, and both concentrations of BDE-28 and BDE-47 in PM2.5 were significantly higher in winter + spring than those in summer + autumn. Among the 8 congeners, BDE-209 was predominant, accounting for 73.9% of the Σ8PBDEs concentrations. Traffic area, industrial area, residential area and discharge of electronic industries had significant positive influences on PBDE concentrations in PM2.5. Both vegetation area and water area were significantly negatively correlated with PBDE levels in PM2.5. Significantly negative correlation was also found between PBDE concentrations in PM2.5 and the relative humidity. The ranking of estimated inhalation exposure doses of PBDEs via PM2.5 inhalation were toddlers (1.74 pg/kg b.w./day) > children (1.33 pg/kg b.w./day) > adults (1.26 pg/kg b.w./day) > teenagers (0.64 pg/kg b.w./day), and toddlers had a highest risk to expose to PBDEs by PM2.5. To our knowledge, the present study is the first to reveal the spatiotemporal variability of PBDEs in PM2.5 of Shenzhen, China.

Toxaphene levels in retail food from the Pearl River Delta area of South China and an assessment of dietary intake.

Limited literature exists on toxaphene contamination in food worldwide, particularly in mainland China. In this study, three toxaphene congeners, Parlar 26 (B8-1413), Parlar 50 (B9-1679) and Parlar 62 (B9-1025), were analyzed in five different food categories from the Pearl River Delta Area in China using isotope dilution high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS), and toxaphene levels in food were reported and toxaphene dietary intake by local residents estimated. The results showed that fish contained the highest toxaphene level with a median of 12.87 pg/g wet weight (ww), followed by poultry meat, egg products, livestock meat and vegetable, which had median levels of 5.8, 2.2, 1.89 and 0.67 pg/g ww, respectively. Parlar 50 and Parlar 26 were the predominant characteristic congeners in fish, and Parlar 26 was the predominant congener not only in poultry products and eggs, but also in livestock and vegetable. The estimated average daily intake found by local residents was 35.57 pg/kg body weight/day. Overall toxaphene levels and estimated dietary intake in the Pearl River Delta Area of South China are far lower than the European Maximum Residue Limits (EU MRLs), the German MRL for fish, and other international literature data. Therefore, the risk of adverse health effects from dietary intakes of toxaphene for the local residents is not considerable at the current time, but follow-ups are warranted to study dynamic changes of toxaphene in food in this area.

[Levels of polychlorinated dibenzo-p-dioxins and dibenzofurans in airborne fine particulate matter and inhalation risk assessment for local residents of Shenzhen].

OBJECTIVE: To explore the levels and congener profiles of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in airborne fine particulate matter (PM25) in Shenzhen and roughly discuss its correlations between PM25 concentration and meteorological factors. METHODS: The high volume air samplers were used to collect the samples in six sampling sites in respective winter and spring phase and summer and autumn phase. Referring to the US EPA TO-9A for dioxins detection methods, the concentrations of the 17 polychlorinated dibenzo-p-dioxins and dibenzofurans in airborne fine particulate matter were determined by HRGC/HRMS. RESULTS: The total concentrations of PCDD/Fs ranged from 0.32 to 9.35 pg/m3, with average of 2.45 pg/ m3. The TEQ concentrations ranged from 0.006 to 0.388 pg I-TEQ/m3, with average of 0.095 pg I-TEQ/m3. The four abundant congeners were found to be OCDD (36.49%), 1, 2, 3, 4, 6, 7, 8-HpCDF (14.89%), OCDF (13.34%) and 1, 2, 3, 4, 6, 7, 8-HpCDD (10.92%). 2, 3, 4, 7, 8-PeCDF was the dominant contributor to toxicity equivalent (TEQ), accounting for 34.65%. Positive relationship was found between the levels of fine particle-bound PCDD/Fs and PM2.5 concentration (r(s) = 0.794, P = 0.006), whereas no correlation was observed for temperature, humidity and atmospheric pressure. Inhalation exposure to PCDD/Fs were 0. 023 pg I-TEQ/(kg · d) for adult and 0.035 pg I-TEQ/(kg · d) for children during winter and spring and relatively higher than those during summer and autumn (0.014 pg I-TEQ/(kg · d). for adult and 0.021 pg I-TEQ/(kg · d) for children respectively). CONCLUSION: The levels of PCDD/Fs in airborne fine particle-bound samples collected in Shenzhen were lower than those in Hangzhou and Beijing.