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Long-term temperature variability and the incidence of cardiovascular diseases: A large, representative cohort study in China Texte intégral
2021
Kang, Yuting | Tang, Haosu | Zhang, Linfeng | Wang, Su | Wang, Xin | Chen, Zuo | Zheng, Congyi | Yang, Ying | Wang, Zengwu | Huang, Gang | Gao, Runlin
In the context of global climate change, far less is known about the impact of long-term temperature variability (TV), especially in developing countries. The current study aimed to estimate the effect of long-term TV on the incidence of cardiovascular disease (CVD) in China. A total of 23,721 individuals with a mean age of 56.15 years were enrolled at baseline from 2012 to 2016 and followed up during 2017–2019. TV was defined as the standard deviation of daily temperatures during survey years and was categorized into tertiles (lowest≤ 8.78 °C, middle = 8.78–10.07 °C, highest ≥ 10.07 °C). The Cox proportional hazards regression was used to estimate the multivariable-adjusted hazard ratio (HR) between TV and CVD. During the median follow-up of 4.65 years, we ascertained 836 cases of incident CVD. For per 1 °C increase in TV, there was a 6% increase of CVD (HR = 1.06 [95% confidence interval (CI): 1.01–1.11]). A significant positive trend was observed between CVD risk and increasing levels of TV compared to the lowest tertile [HR = 1.34 (95% CI: 1.13–1.59) for the medium tertile, HR = 1.72 (95% CI: 1.35–2.19) for the highest tertile, Pₜᵣₑₙd < 0.001]. Exposure to high TV would lose 2.11 disease-free years for the population aged 35–65 years and 66 CVD cases (or 7.95% cases) could been attributable to TV higher than 8.11 °C in the current study. The current findings suggested that long-term TV was associated with a higher risk of CVD incidence, it is needed to reduce the TV-related adverse health effect.
Afficher plus [+] Moins [-]FeS2/carbon felt as an efficient electro-Fenton cathode for carbamazepine degradation and detoxification: In-depth discussion of reaction contribution and empirical kinetic model Texte intégral
2021
Cui, Tingyu | Xiao, Zhihui | Wang, Zhenbei | Liu, Chao | Song, Zilong | Wang, Yiping | Zhang, Yuting | Li, Ruoyu | Xu, Bingbing | Qi, Fei | Ikhlaq, Amir
Carbamazepine (CBZ) decay by electro-Fenton (EF) oxidation using a novel FeS₂/carbon felt (CF) cathode, instead of a soluble iron salt, was studied with the aim to accelerate the reaction between H₂O₂ and ferrous ions, which helps to produce more hydroxyl radicals (•OH) and eliminate iron sludge. First, fabricated FeS₂ and its derived cathode were characterized by scanning electron microscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. Anodes were then screened, with DSA (Ti/IrO₂–RuO₂) showing the best performance under EF oxidation regarding CBZ degradation and electrochemical characterization. Several operating parameters of this EF process, such as FeS₂ loading, current density, gap between electrodes (GBE), initial [CBZ], and electrolyte type, were also investigated. Accordingly, a nonconsecutive empirical kinetic model was established to predict changes in CBZ concentration under the given operational parameters. The contribution of different oxidation types to the EF process was calculated using kinetic analysis and quenching experiments to verify the role of the FeS₂-modified cathode. The reaction contributions of anodic oxidation (AO), H₂O₂ electrolysis (EP), and EF oxidation to CBZ removal were 12.81%, 7.41%, and 79.77%, respectively. The •OH exposure of EP and EF oxidation was calculated, confirming that •OH exposure was approximately 22.45-fold higher using FeS₂-modified CF. Finally, the 19 intermediates formed by CBZ degradation were identified by ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry. Accordingly, four CBZ degradation pathways were proposed. ECOSAR software was used to assess the ecotoxicity of intermediates toward fish, daphnia, and green algae, showing that this novel EF oxidation process showed good toxicity reduction performance. A prolonged EF retention time was proposed to be necessary to obtain clean and safe water, even if the targeted compound was removed at an earlier time.
Afficher plus [+] Moins [-]Using a land use regression model with machine learning to estimate ground level PM2.5 Texte intégral
2021
Wong, Pei-Yi | Lee, Hsiao-Yun | Chen, Yu-Cheng | Zeng, Yu-Ting | Chern, Yinq-Rong | Chen, Nai-Tzu | Candice Lung, Shih-Chun | Su, Huey-Jen | Wu, Chih-Da
Ambient fine particulate matter (PM₂.₅) has been ranked as the sixth leading risk factor globally for death and disability. Modelling methods based on having access to a limited number of monitor stations are required for capturing PM₂.₅ spatial and temporal continuous variations with a sufficient resolution. This study utilized a land use regression (LUR) model with machine learning to assess the spatial-temporal variability of PM₂.₅. Daily average PM₂.₅ data was collected from 73 fixed air quality monitoring stations that belonged to the Taiwan EPA on the main island of Taiwan. Nearly 280,000 observations from 2006 to 2016 were used for the analysis. Several datasets were collected to determine spatial predictor variables, including the EPA environmental resources dataset, a meteorological dataset, a land-use inventory, a landmark dataset, a digital road network map, a digital terrain model, MODIS Normalized Difference Vegetation Index (NDVI) database, and a power plant distribution dataset. First, conventional LUR and Hybrid Kriging-LUR were utilized to identify the important predictor variables. Then, deep neural network, random forest, and XGBoost algorithms were used to fit the prediction model based on the variables selected by the LUR models. Data splitting, 10-fold cross validation, external data verification, and seasonal-based and county-based validation methods were used to verify the robustness of the developed models. The results demonstrated that the proposed conventional LUR and Hybrid Kriging-LUR models captured 58% and 89% of PM₂.₅ variations, respectively. When XGBoost algorithm was incorporated, the explanatory power of the models increased to 73% and 94%, respectively. The Hybrid Kriging-LUR with XGBoost algorithm outperformed the other integrated methods. This study demonstrates the value of combining Hybrid Kriging-LUR model and an XGBoost algorithm for estimating the spatial-temporal variability of PM₂.₅ exposures.
Afficher plus [+] Moins [-]Identification of a novel function of a component in the jasmonate signaling pathway for intensive pesticide degradation in rice and environment through an epigenetic mechanism Texte intégral
2021
Ma, Li Ya | Zhai, Xiao Yan | Qiao, Yu Xin | Zhang, Ai Ping | Zhang, Nan | Liu, Jintong | Yang, Hong
Developing a biotechnical system with rapid degradation of pesticide is critical for reducing environmental, food security and health risks. Here, we investigated a novel epigenetic mechanism responsible for the degradation of the pesticide atrazine (ATZ) in rice crops mediated by the key component CORONATINE INSENSITIVE 1a (OsCOI1a) in the jasmonate-signaling pathway. OsCOI1a protein was localized to the nucleus and strongly induced by ATZ exposure. Overexpression of OsCOI1a (OE) significantly conferred resistance to ATZ toxicity, leading to the improved growth and reduced ATZ accumulation (particularly in grains) in rice crops. HPLC/Q-TOF-MS/MS analysis revealed increased ATZ-degraded products in the OE plants, suggesting the occurrence of vigorous ATZ catabolism. Bisulfite-sequencing and chromatin immunoprecipitation assays showed that ATZ exposure drastically reduced DNA methylation at CpG context and histone H3K9me2 marks in the upstream of OsCOI1a. The causal relationships between the DNA demethylation (hypomethylatioin), OsCOI1a expression and subsequent detoxification and degradation of ATZ in rice and environment were well established by several lines of biological, genetic and chemical evidence. Our work uncovered a novel regulatory mechanism implicated in the defense linked to the epigenetic modification and jasmonate signaling pathway. It also provided a modus operandi that can be used for metabolic engineering of rice to minimize amounts of ATZ in the crop and environment.
Afficher plus [+] Moins [-]Endocrine disrupting potential of veterinary drugs by in vitro stably transfected human androgen receptor transcriptional activation assays Texte intégral
2021
Park, Yooheon | Park, Juhee | Lee, Hee-Seok
We describe the androgen receptor (AR) agonistic/antagonistic effects of 140 veterinary drugs regulated in Republic of Korea, by setting maximum residue limits. It was conducted using two in vitro test guidelines of the Organization for Economic Cooperation and Development (OECD)—the AR-EcoScreen AR transactivation (TA) assay and the 22Rv1/MMTV_GR-KO AR TA assay. These were performed alongside the AR binding affinity assay to confirm whether their AR agonistic/antagonistic effects are based on the binding affinity to AR. Prior to conducting the AR TA assay, the proficiency test was passed the proficiency performance criterion for the AR agonist and AR antagonist assays. Among the veterinary drugs tested, four veterinary drugs (dexamethasone, trenbolone, altrenogest, and nandrolone) and six veterinary drugs (cymiazole, dexamethasone, zeranol, phenothiazine, bromopropylate, and isoeugenol) were determined as AR agonist and AR antagonist, respectively in both in vitro AR TA assays. Zeranol exhibited weak AR agonistic effects with a PC₁₀ value only in the 22Rv1/MMTV_GR-KO AR TA assay. Regarding changing the AR agonistic/antagonistic effects through metabolism, the AR antagonistic activities of zeranol, phenothiazine, and isoeugenol decreased significantly in the presence of phase I + II enzymes.These data indicate that various veterinary drugs could have the potential to disrupt AR-mediated human endocrine system. Furthermore, this is the first report providing information on AR agonistic/antagonistic effects of veterinary drugs using in vitro OECD AR TA assays.
Afficher plus [+] Moins [-]Seasonal variations in the mass characteristics and optical properties of carbonaceous constituents of PM2.5 in six cities of North China Texte intégral
2021
Luo, Lining | Tian, Hezhong | Liu, Huanjia | Bai, Xiaoxuan | Liu, Wei | Liu, Shuhan | Wu, Bobo | Lin, Shumin | Zhao, Shuang | Hao, Yan | Sun, Yujiao | Hao, Jiming | Zhang, Kai
Carbonaceous constituents have various adverse impacts on human health, visibility, and climate change. Although comprehensive studies on the characteristics of carbonaceous constituents have been conducted recently, systematic studies covering both the mass characteristics and light-absorption properties of carbonaceous constituents on a regional scale in China are quite limited. In this study, current seasonal measurements of organic carbon (OC) and elemental carbon (EC) in PM₂.₅ were investigated during autumn and winter (1–30 October 2017 and December 18, 2017 to January 17, 2018) in six selected cities located at the eastern foot of the Taihang Mountains: Beijing, Baoding, Shijiazhuang, Handan, Xinxiang, and Zhengzhou. Seasonal variations were similar when Beijing was excluded. The lowest concentrations of OC (18.33 ± 9.39 μg/m³) and EC (7.66 ± 5.64 μg/m³) were observed in Xinxiang (autumn) and Beijing (winter), respectively, while the highest concentrations of OC (38.43 ± 62.10 μg/m³) and EC (12.24 ± 24.67 μg/m³) occurred in Baoding during winter mainly due to elevated fuel combustion for space heating. The results of the potential source contribution function (PSCF) analysis suggested that border zones between several provinces in North China should be highlighted in order to strengthen pollution control. Moreover, by separating the optical properties of brown carbon from those of black carbon, we were able to estimate the contributions of brown carbon to the PM₂.₅ total light-absorption coefficient. The results show that the brown carbon absorption coefficient (at 405 nm) in winter at six sites accounted for 21.2%, 33.3%, 34.7%, 39.1%, 48.6%, and 23.3% of the PM₂.₅ light absorption, which are values that are comparable to the contribution of black carbon in Xinxiang. These results provide a more comprehensive understanding of carbonaceous constituents on a regional scale.
Afficher plus [+] Moins [-]Atmospheric ammonia and its effect on PM2.5 pollution in urban Chengdu, Sichuan Basin, China Texte intégral
2021
Huang, Xiaojuan | Zhang, Junke | Zhang, Wei | Tang, Guiqian | Wang, Yuesi
Controlling ammonia (NH₃) emissions has been proposed as a strategy to mitigate haze pollution. To explore the role of NH₃ in haze pollution in Sichuan Basin, where agricultural activities are intense, hourly in situ data of NH₃, as well as nitric acid and secondary inorganic aerosols (SIAs) were gathered in Chengdu from April 2017 to March 2018. We found that NH₃ had an annual mean concentration of 9.7 ± 3.5 (mean ± standard deviation) μg m⁻³, and exhibited seasonal variations (spring > summer > autumn and winter) due to changes in emission sources and meteorological conditions (particularly temperature). Chengdu's atmosphere is generally NH₃-sufficient, especially in the warm seasons, implying that the formation of SIAs is more sensitive to the availability of nitric acid. However, an NH₃ “sufficient-to-deficient” transition was found to occur during winter pollution periods, and the frequency of NH₃ deficiency increased with the aggravation of pollution. Under NH₃-deficient conditions, the nitrogen oxidation ratio increased linearly with the increase in free NH₃, implying that NH₃ contributes appreciably to the formation of nitrate and thus to high PM₂.₅ loadings. No relationships of NH₃ with fossil fuel combustion–related pollutants were found. The NH₃ emissions from farmland and livestock waste in the suburbs of Chengdu and regional transport from west of Chengdu probably contribute to the occurrence of high PM₂.₅ loading in winter and spring, respectively. These results suggest that to achieve effective mitigation of PM₂.₅ in Chengdu, local and regional emission control of NH₃ and NOx synergistically would be effective.
Afficher plus [+] Moins [-]Haze episodes before and during the COVID-19 shutdown in Tianjin, China: Contribution of fireworks and residential burning Texte intégral
2021
Dai, Qili | Ding, Jing | Hou, Linlu | Li, Linxuan | Cai, Ziying | Liu, Baoshuang | Song, Congbo | Bi, Xiaohui | Wu, Jianhui | Zhang, Yufen | Feng, Yinchang | Hopke, Philip K.
Potential health benefits from improved ambient air quality during the COVID-19 shutdown have been recently reported and discussed. Despite the shutdown measures being in place, northern China still suffered severe haze episodes (HE) that are not yet fully understood, particularly how the source emissions changed. Thus, the meteorological conditions and source emissions in processing five HEs occurred in Beijing-Tianjin-Hebei area were investigated by analyzing a comprehensive real-time measurement dataset including air quality data, particle physics, optical properties, chemistry, aerosol lidar remote sensing, and meteorology. Three HEs recorded before the shutdown began were related to accumulated primary pollutants and secondary aerosol formation under unfavorable dispersion conditions. The common “business as usual” emissions from local primary sources in this highly polluted area exceeded the wintertime atmospheric diffusive capacity to disperse them. Thus, an intensive haze formed under these adverse meteorological conditions such as in the first HE, with coal combustion to be the predominant source. Positive responses to the shutdown measures were demonstrated by reduced contributions from traffic and dust during the final two HEs that overlapped the Spring and Lantern Festivals, respectively. Local meteorological dispersion during the Spring Festival was the poorest among the five HEs. Increased residential burning plus fireworks emissions contributed to the elevated PM₂.₅ with the potential of enhancing the HEs. Our results highlight that reductions from shutdown measures alone do not prevent the occurrence of HEs. To further reduce air pollution and thus improve public health, abatement strategies with an emphasis on residential burning are needed.
Afficher plus [+] Moins [-]Exposure of androgen mimicking environmental chemicals enhances proliferation of prostate cancer (LNCaP) cells by inducing AR expression and epigenetic modifications Texte intégral
2021
Singh, Vipendra Kumar | Pal, Rajesh | Srivastava, Priyansh | Misra, Gauri | Shukla, Yogeshwer | Sharma, Pradeep Kumar
Exposure to environmental endocrine disrupting chemicals (EDCs) is highly suspected in prostate carcinogenesis. Though, estrogenicity is the most studied behavior of EDCs, the androgenic potential of most of the EDCs remains elusive. This study investigates the androgen mimicking potential of some common EDCs and their effect in androgen-dependent prostate cancer (LNCaP) cells. Based on the In silico interaction study, all the 8 EDCs tested were found to interact with androgen receptor with different binding energies. Further, the luciferase reporter activity confirmed the androgen mimicking potential of 4 EDCs namely benzo[a]pyrene, dichlorvos, genistein and β-endosulfan. Whereas, aldrin, malathion, tebuconazole and DDT were reported as antiandrogenic in luciferase reporter activity assay. Next, the nanomolar concentration of androgen mimicking EDCs (benzo[a]pyrene, dichlorvos, genistein and β-endosulfan) significantly enhanced the expression of AR protein and subsequent nuclear translocation in LNCaP cells. Our In silico studies further demonstrated that androgenic EDCs also bind with epigenetic regulatory enzymes namely DNMT1 and HDAC1. Moreover, exposure to these EDCs enhanced the protein expression of DNMT1 and HDAC1 in LNCaP cells. These observations suggest that EDCs may regulate proliferation in androgen sensitive LNCaP cells by acting as androgen mimicking ligands for AR signaling as well as by regulating epigenetic machinery. Both androgenic potential and epigenetic modulatory effects of EDCs may underlie the development and growth of prostate cancer.
Afficher plus [+] Moins [-]Aqueous photodecomposition of the emerging brominated flame retardant tetrabromobisphenol S (TBBPS) Texte intégral
2021
Xu, Haiyan | Li, Yueyue | Lu, Jiaxin | Lu, Junhe | Zhou, Lei | Chovelon, Jean-Marc | Ji, Yuefei
As an emerging brominated flame retardant (BFR), tetrabromobisphenol S (TBBPS) has been frequently detected in the environmental media and organisms. Knowledges on the transformation and fate of TBBPS in both environment and engineering systems are essential to its ecological risk assessment. Herein, we reported the photochemical decomposition of TBBPS in aqueous solution upon 254 nm ultraviolet irradiation (UV₂₅₄). Results show that TBBPS was highly photoreactive, most likely due to the presence of four ortho-bromine substituents. The molar absorption coefficient and quantum yield of TBBPS were found to be pH-dependent, with the monoanionic form being most photoreactive. A series of photoproducts were identified by solid phase extraction (SPE) combined with liquid chromatography-electrospray ionization-triple quadrupole mass spectrometry (LC-ESI(+)-MS/MS. The photolysis of TBBPS likely proceeded through photonucleophilic substitution, photoreductive debromination, and β-scission reactions. A ketocarbene, possibly derived from the lower lying excited triplet state, was proposed to be involved in the photolysis of TBBPS. Ion chromatography analysis revealed that debromination occurred quickly, and the yield of bromide (Br⁻) approached 100% after 90 min irradiation. The presence of SRNOM and MRNOM inhibited the photodegradation rate of TBBPS, which is likely due to the light-screening and physical quenching effects of natural organic matter (NOM). Our results reveal that photolysis is an important process for the attenuation of TBBPS in aquatic system; however, naturally occurring species such as NOM can appreciably retard the decay of TBBPS.
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