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Contaminants of emerging concern in marine areas: First evidence of UV filters and paraben preservatives in seawater and sediment on the eastern coast of Tunisia
2022
Fenni, Ferdaws | Sunyer-Caldú, Adrià | Ben Mansour, Hedi | Díaz-Cruz, M. Silvia
UV filters (UVFs) and paraben preservatives (PBs) are widely used components in many personal care products. However, there has been a rising concern for their endocrine-disrupting effects on wildlife once they reach aquatic ecosystems via recreative activities and wastewater treatment plants effluents. This study addresses UVFs and PBs occurrence in seawater and sediment impacted by tourism and sewage discharges along the coast of Mahdia, center East Tunisia. Samples of water and sediment were collected for 6 months from 3 coastal areas. Among the 14 investigated UVFs, 8 were detected in seawater and 4 were found in sediment. All PBs were present in seawater and only methylparaben (MePB) was detected in sediment. Benzophenone-3 (oxybenzone, BP3), benzocaine (EtPABA), and MePB were present in all water samples with concentrations in the ranges 16.4–66.9, 7.3–37.7, and 17.6–222 ng/L, respectively. However, the highest value, 1420 ng/L, corresponded to octinoxate (EHMC). In sediments, avobenzone (AVO), 4-methyl benzylidene camphor (4MBC), EHMC, 5-methyl-1-H-benzotriazole (MeBZT), and MePB were detected at concentrations within the range 1.1–17.6 ng/g dw, being MePB the most frequently detected (89%). MePB and MBZT presented the highest sediment-water partition coefficients and MePB also showed a positive correlation with total suspended solids’ water content. Overall, pollutants concentrations remained rather constant along the sampling period, showing little seasonal variation. This study constitutes the first monitoring of UVFs and PBs on the Tunisian coastline and provides occurrence data for reference in further surveys in the country.
Afficher plus [+] Moins [-]Fine particulate matter, airway inflammation, stress response, non-specific immune function and buccal microbial diversity in young adults
2022
Lin, Zhijing | Chen, Ping | Yuan, Zhi | Yang, Liyan | Miao, Lin | Wang, Hua | Xu, Dexiang
Fine particulate matter (PM₂.₅) has been associated with risk of oral and respiratory diseases. However, the biological mechanisms of adverse oral and respiratory health response to PM₂.₅ fluctuation have not been well characterized. This study aims to explore the relationships of PM₂.₅ with airway inflammation, salivary biomarkers and buccal mucosa microbiota. We performed a panel study among 40 college students involving 4 follow-ups from August to October 2021 in Hefei, Anhui Province, China. Health outcomes included fractional exhaled nitric oxide (FeNO), salivary biomarkers [C-reactive protein (CRP), cortisol, lysozyme and alpha-amylase] and buccal mucosa microbial diversity. Linear mixed-effect models were applied to explore the cumulative impacts of PM₂.₅ on health indicators. PM₂.₅ was positively correlated with FeNO, CRP, cortisol and alpha-amylase, while negatively with lysozyme. Per 10-μg/m³ increase in PM₂.₅ was linked to maximum increments in FeNO of 10.71% (95%CI: 2.01%, 19.41%) at lag 0–24 h, in CRP of 7.10% (95%CI: 5.39%, 8.81%) at lag 0–24 h, in cortisol of 1.25% (95%CI: 0.44%, 2.07%) at lag 0–48 h, and in alpha-amylase of 2.12% (95%CI: 0.53%, 3.71%) at lag 0–24 h, while associated with maximum decrement in lysozyme of 0.53% (95%CI: 0.12%, 0.95%) at lag 0–72 h. Increased PM₂.₅ was linked to reduction in the richness and evenness of buccal microbe and o_Bacillales and o_Bacteroidales were identified as differential microbes after PM₂.₅ inhalation. Bio-information analysis indicated that immunity system pathway was the most important enriched abundant process altered by PM₂.₅ exposure. In summary, short-term PM₂.₅ exposure may impair oral and respiratory health by inducing inflammatory and stress responses, weakening immune function and altering buccal mucosa microbial diversity.
Afficher plus [+] Moins [-]Short- and medium-chain chlorinated paraffins in honey from China: Distribution, source analysis, and risk assessment
2022
Dong, Shujun | Qi, Suzhen | Zhang, Su | Wang, Yaxin | Zhao, Yin | Zou, Yun | Luo, Yiming | Wang, Peilong | Wu, Liming
Chlorinated paraffins (CPs) are industrial chemicals produced in large quantities. Short-chain CPs (SCCPs) were classified as persistent organic pollutants under the Stockholm Convention in 2017. Medium-chain CPs (MCCPs) became candidate persistent organic pollutants in 2021. CPs are now ubiquitously found in the environment. Honey bees can be exposed to CPs during foraging, and this exposure subsequently results in the contamination of honey and other bee products along with colony food production and storage. Here, SCCP and MCCP concentrations in honey collected from Chinese apiaries in 2015 and 2021 were determined. Total CP concentrations in honey from 2021 to 2015 were comparable, but the ratio of MCCPs/SCCPs was higher in 2021 than in 2015. SCCP and MCCP congener group profiles in all honey samples were similar and dominated by C₁₀–₁₁Cl₆–₇ and C₁₄Cl₆–₇, respectively. MCCP concentrations were also higher than SCCP concentrations in bees, pollen, and wax but not in bee bread, which were all collected in 2021. The order of average CP concentrations was determined as wax > bee > pollen > bee bread > honey. Poor relationships were found between SCCP concentrations in honey and other samples, but a relationship between MCCP concentrations in honey and other samples was observed. Migration tests of CPs in plastic bottles showed essentially no migration into honey during storage. The risks to humans from CPs in honey are low.
Afficher plus [+] Moins [-]PM2.5 induces pulmonary microvascular injury in COPD via METTL16-mediated m6A modification
2022
Guo, Xiaolan | Lin, Yuyin | Lin, Yingnan | Zhong, Yue | Yu, Hongjiao | Huang, Yibin | Yang, Jingwen | Cai, Ying | Liu, FengDong | Li, Yuanyuan | Zhang, Qian-Qian | Dai, Jianwei
Fine particulate matter (PM2.5) exposure is a significant cause of chronic obstructive pulmonary disease (COPD), but the detailed mechanisms involved in COPD remain unclear. In this study, we established PM2.5-induced COPD rat models and showed that PM2.5 induced pulmonary microvascular injury via accelerating vascular endothelial apoptosis, increasing vascular permeability, and reducing angiogenesis, thereby contributing to COPD development. Moreover, microvascular injury in COPD was validated by measurements of plasma endothelial microparticles (EMPs) and serum VEGF in COPD patients. We then performed m⁶A sequencing, which confirmed that altered N⁶-methyladenosine (m⁶A) modification was induced by PM2.5 exposure. The results of a series of experiments demonstrated that the expression of methyltransferase-like protein 16 (METTL16), an m⁶A regulator, was upregulated in PM2.5-induced COPD rats, while the expression of other regulators did not differ upon PM2.5-induction. To clarify the regulatory effect of METTL16-mediated m⁶A modification induced by PM2.5 on pulmonary microvascular injury, cell apoptosis, permeability, and tube formation, the m⁶A level in METTL16-knockdown pulmonary microvascular endothelial cells (PMVECs) was evaluated, and the target genes of METTL16 were identified from a set of the differentially expressed and m⁶A-methylated genes associated with vascular injury and containing predicted sites of METTL16 methylation. The results showed that Sulfatase 2 (Sulf2) and Cytohesin-1 (Cyth1) containing the predicted METTL16 methylation sites, exhibited higher m⁶A methylation and were downregulated after PM2.5 exposure. Further studies demonstrated that METTL16 may regulate Sulf2 expression via m⁶A modification and thereby contribute to PM2.5-induced microvascular injury. These findings not only provide a better understanding of the role played by m⁶A modification in PM2.5-induced microvascular injury, but also identify a new therapeutic target for COPD.
Afficher plus [+] Moins [-]Long-term exposure to PM2.5 aggravates pulmonary fibrosis and acute lung injury by disrupting Nrf2-mediated antioxidant function
2022
Zhao, Chen | Pu, Wenyuan | Wazir, Junaid | Jin, Xiaolu | Wei, Lulu | Song, Shiyu | Su, Zhonglan | Li, Jiabin | Deng, Yijun | Wang, Hongwei
Epidemiological studies have indicated that exposure to ambient air-borne fine particulate matter (PM2.5) is associated with many cardiopulmonary diseases; however, the underlying pathological mechanisms of PM2.5-induced lung injury remain unknown. In this study, we aimed to assess the impact of acute or prolonged exposure to water-insoluble fractions of PM2.5 (PM2.5 particulate) on lung injury and its molecular mechanisms. Balb/c mice were randomly exposed to PM2.5 once (acute exposure) or once every three days for a total of 6 times (prolonged exposure). Lung, BALF and blood samples were collected, and pulmonary pathophysiological alterations were analyzed. Nrf2 knockout mice were adapted to assess the involvement of Nrf2 in lung injury, and transcriptomic analysis was performed to delineate the mechanisms. Through transcriptomic analysis and validation of Nrf2 knockout mice, we found that acute exposure to PM2.5 insoluble particulates induced neutrophil infiltration-mediated airway inflammation, whereas prolonged exposure to PM2.5 insoluble particulate triggered lung fibrosis by decreasing the transcriptional activity of Nrf2, which resulted in the downregulated expression of antioxidant-related genes. In response to secondary LPS exposure, prolonged PM2.5 exposure induced more severe lung injury, indicating that prolonged PM2.5 exposure induced Nrf2 inhibition weakened its antioxidative defense capacity against oxidative stress injury, leading to the formation of pulmonary fibrosis and increasing its susceptibility to secondary bacterial infection.
Afficher plus [+] Moins [-]Appraising regional anthropogenic heat flux using high spatial resolution NTL and POI data: A case study in the Beijing-Tianjin-Hebei region, China
2022
Wang, Yichen | Hu, Deyong | Yu, Chen | Di, Yufei | Wang, Shasha | Liu, Manqing
Rapid urbanization and the aggregation of human activities in cities have resulted in large amounts of anthropogenic heat (AH) emission, which affects urban climate. Quantifying and assessing the AH emission values accurately and analyzing their spatial distribution characteristics is important to understand the energy exchange processes of urban areas. In this study, the high spatial resolution anthropogenic heat flux (AHF) quantification and spatial distribution analysis were conducted using multi-source data in the Beijing-Tianjin-Hebei region (BTH region) of China. First, the AH emission in district and city level were estimated using inventory method based on energy consumption and socio-economic statistical data; Then, AHF spatial quantification models were constructed based on high spatial resolution nighttime light (NTL) data and Point of interests (POI) data, and 130 m × 130 m gridded AHF quantification result in BTH region was realized; Finally, the potential numerical and spatial distribution patterns of AHF were analyzed using various indicators including contribution rate and aggregation index. The results show that: (1) The parameterized index constructed based on NTL and POI data shows a strong correlation with AHF, with R² ranging from 0.79 to 0.94 and a mean absolute error (MAE) value of 0.72 w·m⁻², which can be applied to the quantification of gridded AHF values with high resolution. The highest total AHF in the study area is 214 w·m⁻², and the average value is 2.24 w·m⁻². (2) Considering the sources of AHF, industrial emission sources in BTH region contribute the most to the total AHF, but commercial building emission sources in Beijing have a higher contribution, which can reach 33.8%. (3) Different types of AHF have different spatial aggregation levels. Commercial building emission and human metabolic emission have the highest aggregation level, and transportation emission has the lowest aggregation level.
Afficher plus [+] Moins [-]Legacy and novel brominated flame retardants in air of Ny-Ålesund, Arctic from 2011 to 2019
2022
Xiong, Siyuan | Hao, Yanfen | Fu, Jianjie | Wang, Pu | Yang, Ruiqiang | Pei, Zhiguo | Li, Yingming | Li, An | Zhang, Qinghua | Jiang, Guibin
Concentrations of polybrominated diphenyl ethers (PBDEs) and novel brominated flame retardants (NBFRs) in the atmosphere of Ny-Ålesund, Svalbard, were investigated. Passive air samples were collected for eight consecutive one-year periods from August 2011 to August 2019 at seven Arctic sampling sites. High-resolution gas chromatography coupled with high-resolution mass spectrometry (HRGC-HRMS) and gas chromatography coupled with election capture negative ionization mass spectrometry (GC-NCI-MS) were employed for PBDE and NBFR analysis, respectively. The median concentrations of Ʃ₁₁PBDEs and Ʃ₆NBFRs were 0.6 pg/m³ and 4.0 pg/m³, respectively. Hexabromobenzene and BDE-47 were the most abundant NBFR and PBDE congeners in the atmosphere, accounting for 31% and 24% of ƩNBFR and ƩPBDE concentrations, respectively. ƩNBFR concentration was approximately six times higher than that of ƩPBDEs in the same samples. Among NBFRs, the concentrations of 1,2,3,4,5-pentabromobenzene, 2,3,4,5,6-pentabromobenzene, and 2,3-dibromopropyl-2,4,6-tribromophenyl ether showed increasing temporal variations, with estimated doubling times of 3.0, 3.3, and 2.8 years, respectively. The concentrations of almost all PBDE congeners showed a decreasing variation, with halving times ranging from 2.1 to 9.5 years.
Afficher plus [+] Moins [-]A wide range of toxic VOCs measured by dual-sorbent passive sampling with validation by field online measurements
2022
Lee, Yu-Hsun | Wang, Chieh-Heng | Hsu, Pei-Hsuan | Hsieh, Hsin-Cheng | Wang, Jia-Lin
This study modified a passive sampling technique similar to the US EPA Method 325 A/B method but extended to include more toxic volatile organic compounds (VOCs) under varied climate conditions to enhance field applicability. A mixing chamber was built to determine uptake rates (Us) for the target compounds. It was found that the Us of 27 air toxics previously reported in the literature agreed reasonably well with our findings within 18%, thus proving the chamber's integrity. To broaden the compound coverage, both Carbopack X and Carboxen 569 were studied for a suite of toxic VOCs to meet stringent quality control (QC) criteria of correlation coefficients (R-square), method detection limits (MDL), back diffusion (BD), storage stability, as well as a wide range of climate conditions in temperature and humidity. After excluding the species that failed to pass any of the QC criteria, Carbopack X was found to fit 50 air toxics, whereas Carboxen 569 held 37. After excluding the overlapped species, 61 toxic VOCs can be determined with robust Us for a broad range of climate conditions when the two sorbents are used in pairs. A one-week field measurement was conducted to compare with the online thermal desorption gas chromatography-mass spectrometry (TD-GC-MS) with hourly data resolution. The field passive sampling showed comparable results to the means of the online hourly measurements, despite the high variability of selected target compounds, such as toluene from 0.3 ppbv as the 5th percentile to the maximum of about 80 ppbv. Passive sampling clearly demonstrated the ability to smooth out concentration variability and thus the time-averaging strength of toxic VOCs, revealing its ideal role as an exposure monitor over time. The passive sampling method can be more desired than active sampling or online methods when the aim is simply the knowledge of prolonged time-averaged concentrations.
Afficher plus [+] Moins [-]Characteristics of PM2.5 emissions from six types of commercial cooking in Chinese cities and their health effects
2022
Lyu, Junmeng | Shi, Yongxiang | Chen, Cong | Zhang, Xinqiao | Zhu, Wei | Lian, Zhiwei
Commercial kitchens may pose significant health risks to workers because they generate large quantities of fine particulate matter (PM₂.₅). In our study, the concentrations and emission rates of PM₂.₅ in cooking environments were measured for six types of commercial kitchens that used electricity and natural gas (including traditional Chinese kitchens, western kitchens, teppanyaki kitchens, fried chicken kitchens, barbecue kitchens, and hotpot cooking area). Furthermore, a preliminary health risk assessment of the chefs was undertaken using the annual PM₂.₅ inhalation and PM₂.₅ deposition rates into the upper airways and tracheobronchial and alveolar regions of the human body. Results showed that cooking in the teppanyaki kitchen generated the highest amount of PM₂.₅, with a mean emission rate of 7.7 mg/min and a mean mass concentration of 850.4 ± 533.4 μg/m³ in the breathing zone. Therefore, teppanyaki kitchens pose highest PM₂.₅ exposure risks to chefs, with the highest rate of PM₂.₅ deposition in the upper airways (6.38 × 10⁵ μg/year), followed by Chinese kitchens. The PM₂.₅ concentrations and emission rates of each kitchen varied greatly with the dishes cooked. The mean PM₂.₅ concentration was the highest during Chinese stir-frying, with the peak concentration reaching more than 20,000 μg/m³, followed by pan-frying, deep-frying, stewing, and boiling. A rise in PM₂.₅ concentration was also observed during the start of stir-frying and in the middle to late stages of pan-frying and grilling meat. The results obtained in our study may contribute in understanding the characteristics of PM₂.₅ emissions from various types of commercial kitchens and their health effects.
Afficher plus [+] Moins [-]Microplastics in surface sediments of a highly urbanized wetland
2022
Birami, Farideh Amini | Keshavarzi, Behnam | Moore, Farid | Busquets, Rosa | Zafarani, Seyed Ghasem Ghorbanzadeh | Golshani, Reza | Cheshmvahm, Hamidreza
This study investigates the incidence of MPs in surface sediment samples, collected from the Anzali Wetland, Gillan province, North of Iran. This natural habitat receives municipal wastewater effluents and hosts industries and recreational activities that could release plastic to the wetland. There is need for studies to understand MPs pollution in wetlands. A total of 40 superficial sediment samples were taken covering potential pollution hotspots in the wetland. The average level of MPs was 362 ± 327.6 MP/kg: the highest MPs levels were near the outlet of a highly urbanized river (Pirbazar River) (1380 MP/kg), which runs through Rasht city. This was followed by 1255 MP/kg where there was intense fishing, boating and tourism activities in the vicinity of Bandar-e Anzali city. Fibers were the most common type of MPs (80% of the total MPs detected). The MPs polluting the wetland were predominantly white/transparent (42%), and about 40% of them were >1000 μm. Polypropylene (PP) and polyethylene (PE) prevailed in MPs found. MPs were characterized with polarized light microscopy, Raman spectroscopy, Scanning Electron Microscopy coupled with Energy-Dispersive X-ray spectroscopy. Microplastics levels were found to correlate significantly (p > 0.7) with electrical conductivity (EC) and sand-size fraction of the sediments. Coarse-grained sediments presented large capacity to lodge the MPs. This study can be used to establish protection policies in wetlands and newly highlights the opportunity of intercepting MPs in the Anzali Wetland, which are generally >250 μm, before they fragment further.
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