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Source profiles, emission factors and associated contributions to secondary pollution of volatile organic compounds (VOCs) emitted from a local petroleum refinery in Shandong Полный текст
2021
Lv, Daqi | Lü, Sihua | Tan, Xin | Shao, Min | Xie, Shaodong | Wang, Lingfeng
An in-depth study was conducted to quantify and characterize VOC emissions from a petroleum refinery located in Shandong, China. The VOC emission inventory established in this study showed that storage tanks were the largest emission source, accounting for 56.4% of total emissions, followed by loading operations, wastewater collection and treatment system, process vents, and equipment leaks. Meanwhile, the localization factors for refining, storage tanks and loading operations were calculated, which were 1.33, 0.75 and 0.31g VOCs/kg crude oil refined. Furthermore, the characteristics of fugitive and organized emissions were determined for various processes and emission sources using a gas chromatography–mass spectrometry/flame ionization detection (GC-MS/FID) system. Most samples contained mainly alkanes, but the total VOC concentrations and key species varied greatly among processes. The source profile of the refinery, synthesized using the weighted average method, indicated that cis-2-butene (14.5%), n-pentane (10.2%), n-butane (7.4%), isopentane (6.5%) and MTBE (5.9%) were the major species released by this refinery. Assessment of O₃ and secondary organic aerosol formation potentials were completed, and the results indicated that cis-2-butene, m/p-xylene, toluene, n-pentane, isopentane, benzene, o-xylene and ethylbenzene were the active species for which treatment should be prioritized.
Показать больше [+] Меньше [-]Association of heating fuel types with mortality and cardiovascular events among non-smokers in China Полный текст
2021
Cao, Xue | Tang, Haosu | Zheng, Congyi | Kang, Yuting | Zhang, Linfeng | Wang, Xin | Chen, Zuo | Yang, Ying | Zhou, Haoqi | Chen, Lu | Huang, Gang | Wang, Zengwu
Only a few prospective studies have investigated the relationship between solid fuel use and cardiovascular disease (CVD) and mortality, and they have reported inconsistent conclusions. This study aimed to investigate the effect of solid fuel heating on the risk of CVD events and all-cause mortality among non-smokers. Data of this sub-study were obtained from the China Hypertension Survey (CHS), and 13,528 non-smoking participants aged 35 or above without self-reported medical history of CVD were enrolled between October 2012 and December 2015. CVD events and all-cause mortality were followed up in 2018 and 2019. The type of primary heating fuel was categorized as clean fuel (natural gas and electricity) and solid fuel (coal, wood, and straw). Cox regression was applied to evaluate the relationship between solid fuel use and CVD events and all-cause mortality. Of the 13,528 non-smoking participants, the mean age was 55.4 ± 13.1 years. During the median follow-up of 4.93 years, 424 participants developed fatal or nonfatal CVD (stroke, 273; coronary heart disease, 119; and other cardiovascular events, 32) and 288 died from all causes. The cumulative incidence of fatal and nonfatal CVD and all-cause mortality were 6.78 and 4.62 per 1000 person-years, respectively. Solid fuel heating was independently associated with an increased risk of fatal or nonfatal stroke and all-cause mortality compared with the use of clean fuels, the fully adjusted hazard ratios (HRs), and 95% confidence intervals (CI) were 1.44 (1.00–2.08) and 1.55 (1.10–2.17), respectively. The relationship between solid fuel heating and fatal and nonfatal CVD events was non-significant (HR = 1.19; 95% CI: 0.89–1.59). Solid fuel heating is longitudinally associated with a higher risk of stroke and all-cause mortality in non-smoking Chinese. Switching to cleaner energy sources for heating may be important for reducing the risk of CVD and mortality.
Показать больше [+] Меньше [-]Occurrence and abundance of poly- and perfluoroalkyl substances (PFASs) on microplastics (MPs) in Pearl River Estuary (PRE) region: Spatial and temporal variations Полный текст
2021
Cheng, Yao | Mai, Lei | Lu, Xingwen | Li, Zhe | Guo, Ying | Chen, Da | Wang, Fei
Although the occurrence and distribution of various chemicals on microplastics (MPs) has been widely studied, little was known about the concentrations of poly- and perfluoroalkyl substances (PFASs) on MPs. In this study, MPs from eight rivers draining into Pearl River Estuary (PRE) region were collected and analyzed. Higher concentrations of PFASs on MPs (105–9.07 × 10³ ng g⁻¹) were found in the drain outlets receiving wastewater from most urbanized cities with large population densities. On the other hand, lower concentrations of PFASs on MPs (10.3–227.8 ng g⁻¹) were found in the drain outlets receiving wastewater mostly from agricultural and forested areas. Specially, 8:2 disubstituted polyfluoroalkyl phosphates (8:2 diPAP) was detected with the highest frequency, in 92.5% of the samples. Furthermore, a positive Spearman correlation was found between 6:2 disubstituted polyfluoroalkyl phosphates (6:2 diPAP) and perfluorotetradecanoic acid (PFTeDA) (rₛ = 0.621, p = 0.012), indicating they might share similar sources. PFASs on MPs were found to vary significantly with different seasons. Higher concentrations of PFASs on MPs were found in dry seasons, while lower concentrations were observed in wet seasons. The results of this study should be important for the understanding of PFAS occurrence and distribution on MPs and the partitioning mechanism of PFASs on MPs in estuary systems.
Показать больше [+] Меньше [-]Urban mining of obsolete computers by manual dismantling and waste printed circuit boards by chemical leaching and toxicity assessment of its waste residues Полный текст
2021
Arya, Shashi | Patel, Aneri | Kumar, Sunil | Pau-Loke, Show
Waste residues and acidic effluents (post-processing of E-waste) released into the local surroundings cause perilous environmental threats and potential risks to human health. Only limited research and information are available toward the sustainable management of waste residues generated post resource recovery of E-waste components. In the present study, the manual processing of obsolete computer (keyboard, monitor, CPU, and mouse) and chemical leaching of waste printed circuit boards (WPCBs) (motherboard, hard drive, DVD drive, and power supply) were performed for urban mining. The toxicity characteristics of typical pollutants in the residues of the WPCBs (post chemical leaching) were studied by toxicity characteristics leaching procedure (TCLP) test. Manual dismantling techniques resulted in an efficient urban mining concept with an overall average profit estimation of INR 2513.73/US$ 34.59. The chemical leaching of WPCBs showed a high concentration of metal leaching like Cu (229662 ± 575.3 mg/kg) and Pb (36785.67 ± 13.07 mg/kg) in the motherboard after stripping epoxy coating. The toxicity test revealed that the concentration of Cu (245.746 ± 0.016 mg/l) in the treated waste residue and Cu (430.746 ± 0.0015 mg/l) and Pb (182.09 ± 0.0035 mg/l) in the non-treated waste residue exceeded the threshold limit. The concentrations of other elements As, Cd, Co, Cr, Ag, Mn, Zn, Ni, Fe, Se, and In were within the permissible limit. Hence, the waste residue stands non-hazardous except Cu and Pb. Stripping out the epoxy coating of WPCBs enhances the metal leaching concentrations. The study highlighted that efficient and appropriate E-waste urban mining has immense potential in tracing the waste scrap into secondary resources. This study also emphasized that the final processed waste residue (left unattended or discarded due to lack of appropriate skill and technology) can be taken into consideration and exploited for value-added materials.
Показать больше [+] Меньше [-]Toxicity assessment and underlying mechanisms of multiple metal organic frameworks using the green algae Chlamydomonas reinhardtii model Полный текст
2021
Lee, Patsy | Shang, Shanshan | Shang, Jin | Wang, Wen-Xiong
Metal-organic frameworks (MOFs) are an emerging class of materials which have garnered increasing attention for their utility as adsorbents and photocatalysts in water treatment. Nevertheless, the environmental risks of MOFs, especially their underlying impacts on aquatic organisms, are not fully explored. Herein, the toxicity of multiple representative MOFs was systematically assessed using a freshwater green alga (Chlamydomonas reinhardtii) model. Six typical MOFs with different metal nodes or organic linkers, including four transition metal incorporated aluminum-based porphyrin MOFs [pristine Al-PMOF, Al-PMOF (Cu), Al-PMOF (Ni), and Al-PMOF (Co)], one amine-functionalized MOF NH₂-MIL-125 (Ti), and one bimetallic Hofmann MOF (NiCo-PYZ), were successfully synthesized and characterized. All the tested MOFs significantly reduced the chlorophyll content and inhibited the algal growth, with the most toxic materials being NiCo-PYZ and Al-PMOF (Cu). Distinct toxic mechanisms were observed for the tested MOFs. Metal ion release was the primary cause for algal toxicity induced by NiCo-PYZ. The algal toxicity induced by porphyrin MOFs could be explained by the combined effects of metal ion release and nutrient adsorption, agglomeration and physical interactions, and reactive oxygen species generation. NH₂-MIL-125 (Ti) showed higher stability and more biocompatibility than the other tested MOFs. MOFs concentrations with no harmful effects to algae can be taken as the threshold values for safe use and discharge of MOFs. The ecotoxicological risks of MOFs should be considered as the applied concentrations of MOFs at mg/mL levels in environmental remediation were much higher than the no harmful effect thresholds.
Показать больше [+] Меньше [-]Multigeneration toxicity of Geunsami® (a glyphosate-based herbicide) to Allonychiurus kimi (Lee) (Collembola) from sub-individual to population levels Полный текст
2021
Wee, June | Lee, Yun-Sik | Kim, Yongeun | Lee, Yong Ho | Lee, Sung-Eun | Hyun, Seunghun | Cho, Kijong
Glyphosate-based herbicide (GBH) is the most widely used herbicide worldwide and has long been considered to have significantly low toxicity to non-target soil invertebrates based on short-term toxicity tests (<56 d). However, long-term GBH toxicity assessment is necessary as GBH is repeatedly applied in the same field annually because of the advent of glyphosate-resistant crops. In this study, a multigeneration test was conducted where Allonychiurus kimi (Collembola) was exposed to GBH for three generations (referred to as F₀, F₁, and F₂) to evaluate the long-term toxic effect. The endpoints used were adult survival and juvenile production for the individual level toxicity assessment. Phospholipid profile and population age structure were the endpoints used for sub-individual and population levels, respectively. GBH was observed to have no negative effects on adult survivals of all generations, but juvenile production was found to decrease in a concentration-dependent manner, with EC₅₀s being estimated as 572.5, 274.8, and 59.8 mg a.i. kg⁻¹ in the F₀, F₁, and F₂ generations, respectively. The age structure of A. kimi population produced in the test of all generations was altered by GBH exposure, mainly because of the decrease in the number of young juveniles. Further, differences between the phospholipid profiles of the control and GBH treatments became apparent over generations, with PA 16:0, PA 12:0, and PS 42:0 lipids not being detected at the highest concentration of 741 mg kg⁻¹ in F₂. Considering all our findings from sub-individual to population levels, repeated and long-term use of GBH could have significantly higher negative impacts on non-target soil organisms than expected.
Показать больше [+] Меньше [-]Airborne particulate matter induces oxidative damage, DNA adduct formation and alterations in DNA repair pathways Полный текст
2021
Quezada-Maldonado, Ericka Marel | Sánchez-Pérez, Yesennia | Chirino, Yolanda I. | García-Cuellar, Claudia M.
Air pollution, which includes particulate matter (PM), is classified in group 1 as a carcinogen to humans by the International Agency for Research in Cancer. Specifically, PM exposure has been associated with lung cancer in patients living in highly polluted cities. The precise mechanism by which PM is linked to cancer has not been completely described, and the genotoxicity induced by PM exposure plays a relevant role in cell damage. In this review, we aimed to analyze the types of DNA damage and alterations in DNA repair pathways induced by PM exposure, from both epidemiological and toxicological studies, to comprehend the contribution of PM exposure to carcinogenesis. Scientific evidence supports that PM exposure mainly causes oxidative stress by reactive oxygen species (ROS) and the formation of DNA adducts, specifically by polycyclic aromatic hydrocarbons (PAH). PM exposure also induces double-strand breaks (DSBs) and deregulates the expression of some proteins in DNA repair pathways, precisely, base and nucleotide excision repairs and homologous repair. Furthermore, specific polymorphisms of DNA repair genes could lead to an adverse response in subjects exposed to PM. Nevertheless, information about the effects of PM on DNA repair pathways is still limited, and it has not been possible to conclude which pathways are the most affected by exposure to PM or if DNA damage is repaired properly. Therefore, deepening the study of genotoxic damage and alterations of DNA repair pathways is needed for a more precise understanding of the carcinogenic mechanism of PM.
Показать больше [+] Меньше [-]Identification and quantification of microplastic particles in drinking water treatment sludge as an integrative approach to determine microplastic abundance in a freshwater river Полный текст
2021
Siegel, Henrik | Fischer, Franziska | Lenz, Robin | Fischer, Dieter | Jekel, Martin | Labrenz, Matthias
Microplastic (MP) has been detected ubiquitously in freshwater systems. Until now MP sampling, however, is predominantly based on short-term net or pumping and filtration systems which can only provide snapshots of MP abundance; especially in flowing water bodies. To improve representativeness in the determination of MP occurrences in these aquatic compartments, an integrative approach that covers larger water volumes for a longer period of time is required. In this regard, surface water supplied drinking water treatment plants (DWTPs) represent an opportunity. In DWTPs, suspended solids from thousands of cubic metres of raw water are continuously removed over several hours and enriched in coagulation/flocculation and filtration processes. Our hypothesis was that MP is also removed to a full extent, like suspended solids, and that an integrative approach for identification and quantification in raw water can be derived from the analysis of MP in the treatment sludge. To prove this hypothesis, treatment sludge from a riverside DWTP (Warnow river, North-Eastern Germany) was analysed for MP > 50 μm. A sample purification protocol overcoming potential matrix effects caused by coagulants and flocculants was developed and validated. MP was analysed using micro-Raman spectroscopy. MP occurrence determined for the Warnow river was compared with in situ reference sampling using an established pumping and filtration system at relatively stable flow conditions. As result, the number of MP particles derived from treatment sludge was extrapolated to 196 ± 42 m⁻³ for the Warnow river and is statistically insignificantly different from 233 ± 36 m⁻³ identified by conventional water sampling. In addition, the polymer distribution and particles shape indicated the validity of the integrative concept. Consequently, the determination of MP abundance for freshwater systems based on DWTP treatment sludge represents an adequate method to estimate MP concentrations in flowing waters in an integrative way.
Показать больше [+] Меньше [-]Comparative physicochemical properties and toxicity of organic UV filters and their photocatalytic transformation products Полный текст
2021
Law, Japhet Cheuk-Fung | Huang, Yanran | Chow, Chi-Hang | Lam, Tsz-Ki | Leung, Kelvin Sze-Yin
Transformation products (TPs) of micropollutants contaminating our water resources have become an emerging issue due to the potential threats they pose to environmental and human health. This study investigated the transformation chemistry, toxicity, physicochemical properties and environmental behavior resulting from photocatalytic transformation of organic UV filters as model micropollutants. 3-Benzylidene camphor (3-BC), 4-hydroxybenzophenone (4-HB) and octocrylene (OC) were effectively degraded by UV-A/TiO₂ treatment, with TPs identified and characterized with high resolution mass spectrometry. Nitrated-TPs were observed to be formed in the presence of nitrite and nitrate for 3-BC and 4-HB, suggesting that the transformation process could be altered by components in the water matrix. Vibrio fischeri bioluminescence inhibition assay revealed an increase in toxicity of TPs derived from photocatalytic treatment, with quantitative structure-activity relationship model (ECOSAR) predicted an enhanced toxicity of individual TPs' after transformation. Assessment of physicochemical properties and environmental behavior suggested that TPs as compared to parent organic UV filters, may represent even greater hazards due to their increased water solubility, persistence and mobility – in addition to retaining the parent organic UV filter's toxicity. The results provide important information relevant to the potential risks for the selected organic UV filters, and their corresponding transformation products.
Показать больше [+] Меньше [-]Identification of (anti-)androgenic activities and risks of sludges from industrial and domestic wastewater treatment plants Полный текст
2021
Hu, Xinxin | Shi, Wei | Wei, Si | Zhang, Xiaowei | Yu, Hongxia
The annual production of sludges is significant all over the world, and large amounts of sludges have been improperly disposed by random dumping. The contaminants in these sludges may leak into the surrounding soils, surface and groundwater, or be blown into the atmosphere, thereby causing adverse effects to human health. In this study, the (anti-)androgenic activities in organic extracts of sludges produced from both industrial and domestic wastewater treatment plants (WWTPs) were examined using reporter gene assay based on MDA-kb2 cell lines and the potential (anti-)androgenic risks were assessed using hazard index (HI) based on bioassays. Twelve of the 18 samples exhibited androgen receptor (AR) antagonistic activities, with AR antagonistic equivalents ranging from 1.2 × 10² μg flutamide/g sludge to 1.8 × 10⁴ μg flutamide/g sludge; however, no AR agonistic activity was detected in any of the tested samples. These 12 sludges were all from chemical WWTPs; no sludges from domestic WWTPs displayed AR antagonistic activity. Aside from wastewater source, treatment scale and technology could also influence AR antagonistic potencies. The HI values of all the 12 sludges exceeded 1.0, and the highest HI value was above 3.0 × 10³ for children; this indicates that these sludges might cause adverse effects to human health and that children are at a greater risk than adults. The anti-androgenic potencies and risks of the subdivided fractions were also determined, and medium-polar and polar fractions were found to have relatively high detection rates and contribution rates to the AR antagonistic potencies and risks of the raw sample extracts.
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