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Distribution and source of and health risks associated with polybrominated diphenyl ethers in dust generated by public transportation
2022
Jin, Mantong | Zhang, Shunfei | Ye, Nanxi | Zhou, Shanshan | Xu, Ziyu
Carcinogenic and neurotoxic polybrominated diphenyl ethers (PBDEs) are environmentally ubiquitous and have been widely investigated. However, little is understood regarding their pollution status, sources, and potential risk to persons in public transportation microenvironments (PTMs). We collected 60 dust samples from PTMs and then selected four materials typical of bus interiors to determine the sources of PBDEs in dust using principal component analysis coupled with Mantel tests. We then evaluated the risk of PBDEs to public health using Monte Carlo simulations. We found that PBDE concentrations in dust were 2-fold higher in buses than at bus stops and that brominated diphenyl ether (BDE)-209 was the main pollutant. The number of buses that passed through a bust stop contributed to the extent of PBDE pollution, and the primary potential sources of PBDEs in dust were plastic handles and curtains inside buses; BDE-209 and BDE-154 were the main contributors of pollution. We found that health risk was 8-fold higher in toddlers than in adults and that the reference doses of PBDEs in dust were far below the United States Environmental Protection Agency limits. Our findings provide a scientific basis that may aid in preventing PBDE pollution and guiding related pollution management strategies in PTMs.
اظهر المزيد [+] اقل [-]Insights into the long-term fates and impacts of polybrominated diphenyl ethers in sediment samples in Taiwan: The national project for background monitoring of the environmental distribution of chemical substances (BMECs)
2022
Zhang, Weixiang | Lu, Quang-Oai | Chen, Hsiu-Ling | Hsu, Ning-Syuan | Lee, Ching-Chang
This study aimed to evaluate the impact factors and effectiveness of management policies on the presence of polybrominated diphenyl ethers (PBDEs) in sediment samples in Taiwan from the last 10 years. Twenty-four PBDE congeners were detected in 838 sediment samples collected from 4 stages (2006–2019) in 30 principal rivers, based on the national project for background monitoring of the environmental distribution of chemical substances. The ΣPBDE concentrations in the 4 stages ranged from 30.00 to 147.10 ng/g dw, 6.03–15.30 ng/g dw, 4.99–7.00 ng/g dw, and 1.20–2.10 ng/g dw in the northern, southern, central, and eastern areas, respectively. The concentrations of PBDEs (e.g., penta-BDE and octa-BDE) in sediment samples notably decreased (−6 to −73%) as the Taiwan Environmental Protection Administration implemented policies banning PBDEs (except deca-BDE). The PBDEs levels of the sediment samples collected in the dry season were higher than those collected in the wet season. The levels of ΣPBDEs in sediment samples were affected by season, the amount of general waste present, and nearby PBDE-related factories and e-waste recycling facilities. Reducing the release of PBDEs, especially deca-BDE, through sound waste management and recycling practices is still needed to improve environmental sustainability in Taiwan.
اظهر المزيد [+] اقل [-]Cross-sectional and longitudinal relationships between urinary 1-bromopropane metabolite and pulmonary function and underlying role of oxidative damage among urban adults in the Wuhan-Zhuhai cohort in China
2022
Wang, Bin | Fan, Lieyang | Yang, Shijie | Zhou, Min | Mu, Ge | Liu, Wei | Yu, Linling | Yang, Meng | Cheng, Man | Wang, Xing | Qiu, Weihong | Shi, Tingming | Chen, Weihong
1-bromopropane is a US Environmental Protection Agency-identified significant hazardous air pollutant with concerned adverse respiratory effect. We aimed to investigate the relationship between 1-bromopropane exposure and pulmonary function and the underlying role of oxidative damage, which all remain unknown. Pulmonary function and urinary biomarkers of 1-bromopropane exposure (N-Acetyl-S-(n-propyl)-L-cysteine, BPMA) and oxidative damage to DNA (8-hydroxy-deoxyguanosine, 8-OHdG) and lipid (8-iso-prostaglandin-F2α, 8-iso-PGF2α) were measured for 3259 Chinese urban adults from the Wuhan-Zhuhai cohort. The cross-sectional relationship of BPMA with pulmonary function and the joint relationship of BPMA and 8-OHdG or 8-iso-PGF2α with pulmonary function were investigated by linear mixed models. The mediating roles of 8-OHdG and 8-iso-PGF2α were evaluated by mediation analysis. Additionally, a panel of 138 subjects was randomly convened from the same cohort to evaluate the stability of BPMA repeatedly measured in urine samples collected over consecutive three days and intervals of one, two, and three years, and to estimate the longitudinal relationship of BPMA with pulmonary function change in three years. We found each 3-fold increase in BPMA was cross-sectionally related to FVC and FEV₁ reductions by 29.88-mL and 25.67-mL, respectively (all P < 0.05). Joint relationship of BPMA and 8-OHdG rather than 8-iso-PGF2α with reduced pulmonary function was observed. Moreover, 8-OHdG significantly mediated 9.44% of the BPMA-related FVC reduction. Findings from the panel revealed a fair to excellent stability (intraclass correlation coefficient: 0.43–0.79) of BPMA in repeated urines collected over a period of three years. Besides, BPMA was longitudinally related to pulmonary function reduction in three years: compared with subjects with persistently low BPMA level, those with persistently high BPMA level had 79.08-mL/year and 49.80-mL/year declines in FVC and FEV₁, respectively (all P < 0.05). Conclusively, 1-bromopropane exposure might impair pulmonary function of urban adult population, and oxidative DNA damage might be a potential mechanism underlying 1-bromopropane impairing pulmonary function especially FVC.
اظهر المزيد [+] اقل [-]Heavy metal pollution of soils and risk assessment in Houston, Texas following Hurricane Harvey
2022
Han, Inkyu | Whitworth, Kristina W. | Christensen, Brian | Afshar, Masoud | An Han, Heyreoun | Rammah, Amal | Oluwadairo, Temitope | Symanski, Elaine
In August 2017, after Hurricane Harvey made landfall, almost 52 inches of rain fell during a three-day period along the Gulf Coast Region of Texas, including Harris County, where Houston is located. Harris County was heavily impacted with over 177,000 homes and buildings (approximately 12 percent of all buildings in the county) experiencing flooding. The objective of this study was to measure 13 heavy metals in soil in residential areas and to assess cancer and non-cancer risk for children and adults after floodwaters receded. Between September and November 2017, we collected 174 surface soil samples in 10 communities, which were classified as “High Environmental Impact” or “Low Environmental Impact” communities, based on a composite metric of six environmental parameters. A second campaign was conducted between May 2019 and July 2019 when additional 204 soil samples were collected. Concentrations of metals at both sampling campaigns were higher in High Environmental Impact communities than in Low Environmental Impact communities and there was little change in metal levels between the two sampling periods. The Pollution Indices of lead (Pb), zinc, copper, nickel, and manganese in High Environmental Impact communities were significantly higher than those in Low Environmental Impact communities. Further, cancer risk estimates in three communities for arsenic through soil ingestion were greater than 1 in 1,000,000. Although average soil Pb was lower than the benchmark of the United States Environmental Protection Agency, the hazard indices for non-cancer outcomes in three communities, mostly attributed to Pb, were greater than 1. Health risk estimates for children living in these communities were greater than those for adults.
اظهر المزيد [+] اقل [-]Spatial distribution, ecological and health risk assessment of organophosphorus pesticides identified in the water of Naseri artificial wetland, Iran
2022
Zarei-Choghan, Mohammad | Jorfi, Sahand | Saki, Amal | Jaafarzadeh, Neamatollah
Agricultural development is inevitable to meet the growing need for food. But along with this development, there are unintended and undesirable consequences for human life and the environment that need, found a solution and corrected. One of the most important adverse consequences of agricultural development is the pollution of surface and groundwater resources, which results from various factors such as soil erosion and improper use of different pesticides. This study aimed to conduct an environmental monitoring program in Naseri wetland to determine the concentrations of organophosphorus pesticides (OPPₛ) in water samples and also to evaluate the potential risks (ecological and health risk assessment) of these pesticides. The salting-out assisted liquid-liquid extraction method was used to extract pesticides. The residual concentrations of OPPₛ evaluated by gas chromatography/mass spectrometry (GC/MS). In this study, the ecological risk of OPPₛ calculated for wetland ecosystem, based on the acute risk quotient (RQᵢ) formula with maximum (RQₘₐₓ), mean (RQₘₑₐₙ), and mixture (RQₘᵢₓ) concentrations of organophosphorus pesticides in the wetland water. Also, to assess the health risk of consuming contaminated fish with organophosphate pesticides, the potential non-carcinogenic and carcinogenic risks were determined by the hazard quotient (Index) (HQ, HI) and incremental lifetime cancer risk (ILCR) indices, respectively. The mean ± SD concentration of OPPₛ (Chlorpyrifos, Malathion, Ethion, Dichlorvos, Trifluralin and Diazinon) in samples of wetland water ranged from 0.14 ± 0.08 to 0.35 ± 0.12 and 0.054 ± 0.06 to 0.2 ± 0.1 (μg/L) in summer and autumn, respectively. The mean ± SD of OPPₛ in fish varied from 0.68 ± 0.86 to 3.94 ± 2.7 (μg/kg). Overall, the concentrations of pesticides in all water and fish samples were below the maximum residue limit (30 μg/kg) during the study period, according to the Environmental Protection Agency (EPA) and the World Health Organization (WHO). The results of acute risk quotient were in summer (RQₘₐₓ = 3.49E-4 to 0.067, RQₘₑₐₙ = 5.8E-5 to 0.029, RQₘᵢₓ = 0.139-0.026, 0.018-3.42E-3) and autumn (RQₘₐₓ = 8E-4 to 0.051, RQₘₑₐₙ = 7.74E-6 to 0.018 RQₘᵢₓ = 0.1–0.013, 6E-3- 1.5E-3). The non-carcinogenic and carcinogenic risk indexes due to fish consumption for adults and children were (HQ = 0.026-4.68E-4, HI = 0.041, ILCR = 1.7E-7) and (HQ = 1.85E-3-1.3E-5, HI = 0.041, ILCR = 5.55E-8), respectively. The risk of OPPₛ was generally low. But cumulative risk (pesticide mixtures), should not be ignored.
اظهر المزيد [+] اقل [-]A first assessment of microplastic abundance in sandy beach sediments of the Paranaguá Estuarine Complex, South Brazil (RAMSAR site)
2022
Mengatto, Mateus Farias | Nagai, Renata Hanae
Here we present the first assessment of microplastic (1–5 mm) abundance in drift line sediments from nineteen sandy beaches at the Paranaguá Estuarine Complex, a subtropical estuarine system from South Brazil. This estuarine system harbors Brazil's second-largest grain port, the Guaraqueçaba Environmental Protection Area, and a RAMSAR site. Sediment samples were washed through a 5 and 1 mm mesh sieve and then visually inspected. We found a total of 398 microplastic particles, of which the majority were foams (63.7%), hard plastic fragments (13.8%), paint fragments (12.8%), and pellets (7.2%). Almost all sampled beaches, including those located within the Guaraqueçaba Environmental Protection Area, were contaminated by microplastics. The most likely microplastic sources for the Paranaguá Estuarine Complex beaches are urban and port activities. However, small communities and marine sources may also contribute to microplastic presence.
اظهر المزيد [+] اقل [-]Heterogeneous environmental regulation and industrial structure upgrading: evidence from China
2022
Wang, Lianghu | Wang, Zhao | Ma, Yatian
There are obvious differences between different types of environmental regulation, which are manifested in different environmental protection tendencies and goals, and there are also significant differences in policy implementation. Therefore, it is an urgent empirical problem to quantitatively evaluate the impact of heterogeneous environmental regulation on the upgrading of industrial structures. Therefore, on the basis of measuring the level of industrial structure upgrading, this paper empirically tests the impact of heterogeneous environmental regulation on industrial structure upgrading. The results show that the upgrading level of China’s industrial structure increased year by year from 2000 to 2018. The three types of environmental regulatory measures have effectively promoted the upgrading of the industrial structure, and the market-incentive environmental regulation (MER) has a significantly higher role in the advancement of the industrial structure than the command-controlled environmental regulation (CER) and the voluntary public participation environmental regulation (VER). With the improvement of regional economic development level, the three types of environmental regulation have gradually become more prominent in promoting the upgrading of industrial structure. In the mechanism test, it is found that technological innovation has a partial mediating effect in the process of CER affecting the upgrading of industrial structure, MER and public VER have a complete mediating effect, while foreign direct investment (FDI) has only a partial mediating effect in the process of the three types of environmental regulation affecting industrial advancement, and there is no mediating effect in the process of influencing the rationalization of industrial structure.
اظهر المزيد [+] اقل [-]Investigating the Environmental Kuznets Curve hypothesis amidst geopolitical risk: Global evidence using bootstrap ARDL approach
2022
Hashmi, Shabir Mohsin | Bhowmik, Roni | Inglesi-Lotz, Roula | Syed, Qasim Raza
Environmental concerns have become one of the top inevitable issues the world has been facing nowadays. Human-induced carbon emissions are the main reasons behind these environmental issues and to reduce them and mitigate their consequences, policymakers globally explore their drivers and determinants continuously. Although several socio-economic factors have been explored that affect the level of emissions, relatively less attention has been paid to geopolitical risk (GPR). Over the past few decades, the world has witnessed a significant rise in GPR with economic and environmental impacts. However, the existing body of literature on the GPR-environment nexus documents the contrasting conclusion, which might cause inconvenience while proposing environmental protection policies. Therefore, the present study reinvestigates the impact of GPR on carbon emissions at the global level. The findings document that, in the short run, a 1% rise in GPR impedes emissions by 3.50% globally. On the contrary, a 13.24% rise in emissions is fostered by a 1% increase in GPR in the long run. Also as was expected, we report that energy consumption leads to higher global emissions in both the short and long run. Next, this study also validates the existence of the environmental Kuznets curve (EKC) hypothesis at the global level. Based on these aforementioned outcomes, we propose several policy recommendations to curb global carbon emissions via GPR accomplish, thus, a few sustainable development goals.
اظهر المزيد [+] اقل [-]Experimental investigation on hydrate dissociation in near-wellbore region caused by invasion of drilling fluid: ultrasonic measurement and analysis
2022
Li, Qingchao | Cheng, Yuanfang | Ansari, Ubedullah | Han, Ying | Liu, Xiao | Yan, Chuanliang
As we all know, development and utilization of clean energy is the only way for society to achieve its sustainable development. Although natural gas hydrates is a new type of clean energy, uncontrollable hydrate dissociation and accompanying methane leakage in drilling operation threaten drilling safety, as well as marine environment. However, the dissociation range of natural gas hydrates around wellbore cannot be reasonably determined in previous investigations, which may lead to the inaccurate estimation of borehole collapse and methane leakage. Then, the marine environment will be greatly damaged or affected. The purpose of the present work is to experimentally explore the dissociation characteristics of gas hydrates around wellbore in drilling operation and analyze the influence law and mechanism of various factors (such as hydrate saturation) on hydrate dissociation. It is expected to provide reference for exploring effective engineering measures to avoid the uncontrolled hydrate dissociation, borehole collapse and accompanying methane leakage. The experimental results demonstrate that acoustic velocity of hydrate-bearing sediment can be accurately expressed as quadratic polynomial of hydrate saturation, which is the theoretical basis for determination of hydrate saturation in subsequent experiments. Owing to the fact that hydrate dissociation is an endothermic reaction, hydrate dissociation gradually slows down in experiment. Throughout the experiment, the maximum dissociation rate at the beginning of the experiment is 8.69 times that at the end of the experiment. In addition, sensitivity analysis found that the increase in the stabilizer concentration in drilling fluid can inhibit hydrate dissociation more effectively than the increase in the hydrate saturation. Hydrate dissociation was completely inhibited when the concentration of soybean lecithin exceeds 0.60wt%, but hydrate dissociation definitely occurs in the near-wellbore region no matter what hydrate saturation is. In this way, based on the requirements of drilling safety and/or environment protection, hydrate dissociation and accompanying methane leakage can be controlled by designing and adjusting the stabilizer concentration in drilling fluid.
اظهر المزيد [+] اقل [-]The role of economic complexity in the environmental Kuznets curve of MINT economies: evidence from method of moments quantile regression
2022
Adebayo, Tomiwa Sunday | Rjoub, Husam | Akadiri, Seyi Saint | Oladipupo, Seun Damola | Sharif, Arshian | Adeshola, Ibrahim
In the face of mounting climate change challenges, reducing emissions has emerged as a key driver of environmental sustainability and sustainable growth. Despite the fact that research has been conducted on the environmental Kuznets curve (EKC), few researchers have analyzed this in the light of economic complexity. Thus, the current research assesses the effect of economic complexity on CO₂ emissions in the MINT nations while taking into account the role of financial development, economic growth, and energy consumption for the period between 1990 and 2018. Using the novel method of moments quantile regression (MMQR) with fixed effects, an inverted U-shape interrelationship is found between economic growth and CO₂ emissions, thus validating the EKC hypothesis. Energy consumption and economic complexity increase CO₂ emissions significantly from the 1st to 9th quantiles. Furthermore, there is no significant interconnection between financial development and CO₂ emissions across all quantiles (1st to 9th). The outcomes of the causality test reveal a feedback causal connection between economic growth and CO₂, while a unidirectional causality is established from economic complexity and energy use to CO₂ emissions in the MINT nations. Based on the findings, we believe that governments should stimulate the financial sector to provide domestic credit facilities to industrialists, investors, and other business enterprises on more favorable terms so that innovative technologies for environmental protection can be implemented with other policy recommendations.
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