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2.
J Hazard Mater ; 459: 132189, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37557042

RESUMO

Herein, a method based on solubility parameter calculation was first used to analyze microplastics in indoor dust. The limit of quantification (LOQ) reached 0.2 mg/g, and the result of reference material SRM 2585 (n = 3) was 14.8 mg/g ± 1.8 %, suggesting satisfying sensitivity and precision. Recoveries of spiking experiments were > 80 % with no obvious matrix interferences observed, except ethylene propylene diene monomer (EPDM) MPs. Further, 69 indoor dust samples were analyzed to verify the method and to assess exposure scenarios for graduate students in Tianjin, China. EPDM was identified in an indoor environment for the first time as the second most widely detected type after PET in this work. The mass-based result is complementary to the outcomes from thermogravimetric analysis-gas chromatography-mass spectrometry and laser direct infrared imaging. Significant correlations were found between total organic carbon (TOC), microplastics, and BDE-209 concentrations, indicating microplastics important contaminant vectors in indoor dust. Dormitory stays and PET contributed the most to health risks among the three exposure scenarios and detected four polymers, respectively. This work provides an approach with the potential for the standardized determination of microplastics in complex environmental matrices and reveals exposure characteristics of indoor dust microplastics.

3.
Anal Bioanal Chem ; 415(17): 3375-3384, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37154936

RESUMO

In organic purity assessment, chromatography separation with a suitable detector is required. Diode array detection (DAD) has been a widely used technique for high-performance liquid chromatography (HPLC) analyses, but its application is limited to compounds with sufficient UV chromophores. Charged aerosol detector (CAD), as a mass-dependent detector, is advantageous for providing a nearly uniform response for analytes, regardless of their structures. In this study, 11 non-volatile compounds with/without UV chromophores were analyzed by CAD using continuous direct injection mode. The RSDs of CAD responses were within 17%. For saccharides and bisphenols, especially, the RSDs were lower (2.12% and 8.14%, respectively). Since bisphenols exist in UV chromophores, their HPLC-DAD responses were studied and compared with CAD responses, with CAD showing a more uniform response. Besides, the key parameters of HPLC-CAD were optimized and the developed method was verified using a Certified Reference Material (CRM, dulcitol, GBW06144). The area normalization result of dulcitol measured by HPLC-CAD was 99.89% ± 0.02% (n = 6), consistent with the certified value of 99.8% ± 0.2% (k = 2). The result of this work indicated that the HPLC-CAD method could be a good complementary tool to traditional techniques for the purity assessment of organic compounds, especially for compounds lacking UV chromophores.


Assuntos
Compostos Benzidrílicos , Fenóis , Cromatografia Líquida de Alta Pressão/métodos , Fenóis/análise , Aerossóis/análise , Compostos Benzidrílicos/análise
4.
J Environ Manage ; 330: 117115, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36587549

RESUMO

Natural capital is a constraint on sustainable development goals. There are multiple methods available for natural capital accounting, many of which are inconsistent with each other in accounting items. Another common defect is an inability to represent both physical and monetary quantities. To address these issues, we integrated the ecological footprint and ecosystem service methods by introducing ecosystem service equivalence factors that facilitate the formulation of a standardized and flexible natural capital accounting framework. Adopting the provinces along the Silk Road Economic Belt (SREB) in China as the target research area, this study calculated and analyzed the spatiotemporal evolution of natural capital utilization and ecological pressure from 2000 to 2020. The results revealed that the supply of natural capital in China's SREB cannot meet consumer demands, resulting in the expansion of the ecological deficits. From 2000 to 2020, the physical and monetary quantities of ecological footprint per capita in the SREB increased by 2.51 and 3.66 times and the ecological carrying capacity per capita decreased by 6.81% in physical terms, gradually increasing by 59.93% in monetary terms. The physical and monetary quantities of ecological deficit per capita continued expanding negatively, at rates of -0.133 nha/cap/yr and -299.837 CNY/cap/yr, respectively. Integrating the physical and monetary dimensions, the sustainability of natural capital in China's SREB was weakening, and the ecological pressure was increasing step by step, from the low-relatively low (L-RL) class to the relatively high-relatively high (RH-RH) class. Ningxia, Chongqing, Shaanxi, Guangxi and Xinjiang were the provinces facing the greatest ecological challenges along the SREB in China, while Qinghai faced the least ecological pressure. These findings provide a reference for the scientific utilization and management of natural capital in provinces along the SREB in China. Additionally, the proposed framework enriches the interactive research achievements of ecological footprint and ecosystem service theories, in ways that not only compensate for the lack of monetary quantity in the ecological footprint, but also have the potential to serve the compilation of China's government-mandated Natural Resource Balance Sheet.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , China , Desenvolvimento Sustentável , Governo , Desenvolvimento Econômico
5.
Accid Anal Prev ; 180: 106905, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36508949

RESUMO

The removal of drivers' active engagement in driving tasks can lead to erratic gaze patterns in SAE Level 2 (L2) and Level 3 (L3) automation, which has been linked to their subsequential degraded take-over performance. To further address how changes in gaze patterns evolve during the take-over phase, and whether they are influenced by the take-over urgency and the location of the human-machine interface, this driving simulator study used a head-up display (HUD) to relay information about the automation status and conducted take-over driving experiments where the ego car was about to exit the highway with variations in the automation level (L2, L3) and time budget (2 s, 6 s). In L2 automation, drivers were required to monitor the environment, while in L3, they were engaged with a visual non-driving related task. Manual driving was also embodied in the experiments as the baseline. Results showed that, compared to manual driving, drivers in L2 automation focused more on the HUD and Far Road (roadway beyond 2 s time headway ahead), and less on the Near Road (roadway within 2 s time headway ahead); while in L3, drivers' attention was predominantly allocated on the non-driving related task. After receiving take-over requests (TORs), there was a gradual diversion of attention from the Far Road to the Near Road in L2 take-overs. This trend changed nearly in proportion to the time within the time budget and it exaggerated given a shorter time budget of 2 s. While in L3, drivers' gaze distribution was similar in the early stage of take-overs for both time budget conditions (2 s vs. 6 s), where they prioritized their early glances to Near Road with a gradual increase in attention towards Far Road. The HUD used in the present study showed the potential to maintain drivers' attention around the road center during automation and to encourage drivers to glance the road earlier after TORs by reducing glances to the instrument cluster, which might be of significance to take-over safety. These findings were discussed based on an extended conceptual gaze control model, which advances our understanding of gaze patterns around control transitions and their underlying gaze control causations. Implications can be contributed to the design of autonomous vehicles to facilitate the transition of control by guiding drivers' attention appropriately according to drivers' attentional state and the take-over urgency.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Humanos , Automação , Tempo de Reação , Veículos Autônomos
6.
Environ Int ; 162: 107153, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35202929

RESUMO

Since December 2019, coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a great challenge to the world's public health system. Nosocomial infections have occurred frequently in medical institutions worldwide during this pandemic. Thus, there is an urgent need to construct an effective surveillance and early warning system for pathogen exposure and infection to prevent nosocomial infections in negative-pressure wards. In this study, visualization and construction of an infection risk assessment of SARS-CoV-2 through aerosol and surface transmission in a negative-pressure ward were performed to describe the distribution regularity and infection risk of SARS-CoV-2, the critical factors of infection, the air changes per hour (ACHs) and the viral variation that affect infection risk. The SARS-CoV-2 distribution data from this model were verified by field test data from the Wuhan Huoshenshan Hospital ICU ward. ACHs have a great impact on the infection risk from airborne exposure, while they have little effect on the infection risk from surface exposure. The variant strains demonstrated significantly increased viral loads and risks of infection. The level of protection for nurses and surgeons should be increased when treating patients infected with variant strains, and new disinfection methods, electrostatic adsorption and other air purification methods should be used in all human environments. The results of this study may provide a theoretical reference and technical support for reducing the occurrence of nosocomial infections.


Assuntos
COVID-19 , SARS-CoV-2 , Aerossóis , Humanos , Isoladores de Pacientes , Medição de Risco
7.
Ecotoxicol Environ Saf ; 231: 113204, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35065505

RESUMO

There has been extensive research on antibiotics exposure in adults by biomonitoring, but the biological mechanisms and potential risks to human health remain limited. In this study, 102 adults aged 26-44 years in Tianjin were studied and 23 common antibiotics in urine were analyzed by Liquid chromatography-mass spectrometry (LC-MS). All antibiotics were detected in urine, with an overall detection frequency of 40.4% (the detection frequencies of phenothiazines, quinolones, sulfonamides, tetracyclines, and chloramphenicol were 77%, 54%, 24%, 28%, and 49%, respectively.). Ofloxacin and enrofloxacin had the highest detection frequencies (85% and 81%), with median concentrations of 0.26 (IQR: 0.05-1.36) and 0.09 (IQR: 0.03-0.14) ng/mL, respectively. Based on health risk assessment, the predicted estimated daily exposures (EDEs) ranged from 0 µg/kg/day to 13.98 µg/kg/day. The hazard quotient (HQ) values of all the antibiotics except ofloxacin and ciprofloxacin were bellow one, which are considered safe. For all blood samples, the mitochondrial DNA (mtDNA) methylation levels in the MT-ATP6 (ranging between 3.86% and 34.18%) were slightly higher than MT-ATP8 and MT-ND5 (ranging between 0.57% and 9.32%, 1.08% and 19.62%, respectively). Furthermore, mtDNA methylation from MT-ATP6, MT-ATP8 and MT-ND5 were measured by bisulfite-PCR pyrosequencing. The association (P < 0.05) was found between mtDNA methylation level (MT-ATP8 and MT-ND5) and individual antibiotics including chlorpromazine, ciprofloxacin, enrofloxacin, norfloxacin, pefloxacin, sulfaquinoxaline, sulfachloropyridazine, chloramphenicol, and thiamphenicol, indicating that persistent exposure to low-dose multiple antibiotics may affect the mtDNA methylation level and in turn pose health risks.


Assuntos
Antibacterianos , DNA Mitocondrial , Adulto , China , Metilação de DNA , Humanos , Medição de Risco
8.
Sci Total Environ ; 806(Pt 2): 150676, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34599951

RESUMO

Natural capital accounting is an essential prerequisite for the harmonious development of human beings and nature and benign interactions between economy and environment. Although the ecological footprint has significantly contributed to sustainability evaluation for many years, the traditional ecological footprint model is limited by lack of value accounting, incomplete account content, neglect of multi-functions of land, and geographical spatial heterogeneity. These limitations reduce the universality of this model. To improve the value accounting of the ecological footprint model, this study takes national hectares (nha) as the measurement unit and includes the freshwater and pollution footprints. The dynamic changes of natural capital from 2000 to 2018 were calculated and analyzed in 31 Chinese provinces. The main findings are summarized here. China's physical quantity of ecological footprint, ecological carrying capacity, and ecological deficit in 2018 was 4.03, 0.79, and -3.24 billion nha, respectively. The energy account contributed most of the physical quantity in the ecological footprint (72.12% of the total). From 2000 to 2018, the physical quantities of the per capita ecological footprint and the per capita ecological deficit increased at 5.49% and 10.08% per annum, respectively, while the physical quantity of the per capita ecological carrying capacity decreased by 0.55% per annum. The physical quantities of the per capita ecological footprint and per capita ecological deficit were spatially distributed, reducing in the order of East > Central > West. The spatial distribution of the physical quantity of the per capita ecological carrying capacity showed the opposite trend. By 2018, China's ecological footprint, ecological carrying capacity, and ecological deficit were valued at 18.09, 12.44 and CNY -5.65 trillion, respectively. Over the 2000-2018 period, the per capita ecological footprint and ecological carrying capacity increased by 495 and CNY 370 per annum, respectively, while the per capita ecological deficit expanded at CNY -125 per annum. The biological account contributed approximately 59.53% of the value quantity of the ecological footprint. Since the twenty-first century, the cumulative effect of excessive consumption has placed increasing pressure on China's ecosystems. On mainland China, only Tibet showed an ecological surplus in 2018. The ecological pressure index decreased in the order of East > Central > West. As Western China has developed extensively and its ecological deficit is rapidly expanding, this region deserves special attention. The most ecologically challenging regions in China are Shanghai, Tianjin, and Beijing. In contrast, Jilin, Qinghai, and Tibet impose low ecological pressure in China. These findings contribute to the standardization and localization of the ecological footprint model in China and provide a reference for regional resource management and ecological construction.


Assuntos
Ecologia , Ecossistema , China , Conservação dos Recursos Naturais , Humanos , Modelos Teóricos
9.
J Environ Sci (China) ; 109: 77-87, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34607676

RESUMO

Ten nitrated polycyclic aromatic hydrocarbons (nPAHs) and 4 oxygenated polycyclic aromatic hydrocarbons (oPAHs) in fine particulate matter (PM2.5) samples from Mount Tai were analyzed during summer (June to August), 2015. During the observation campaign, the mean concentration of total nPAHs and oPAHs was 31.62 pg/m3 and 0.15 ng/m3, respectively. Two of the monitored compounds, namely 9-nitro-anthracene (9N-ANT) (6.86 pg/m3) and 9-fluorenone (9FO) (0.05 ng/m3) were the predominant compounds of nPAHs and oPAHs, respectively. The potential source and long-range transportation of nPAHs and oPAHs were investigated by the positive matrix factorization (PMF) method and the potential source contribution function (PSCF) methods. The results revealed that biomass/coal burning, gasoline vehicle emission, diesel vehicle emission and secondary formation were the dominant sources of nPAHs and oPAHs, which were mainly from Henan province and Beijing-Tianjin-Hebei region and Bohai sea. The incremental life cancer risk (ILCR) values were calculated to evaluate the exposure risk of nPAHs and oPAHs for three group people (infant, children and adult), and the values of ILCR were 7.02 × 10-10, 3.49 × 10-9 and 1.41 × 10-8 for infant, children and adults, respectively. All these values were lower than the standard of EPA (Environmental Protection Agency) (<10-6), indicating acceptable health risk of nPAHs and oPAHs.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Adulto , Poluentes Atmosféricos/análise , Criança , China , Monitoramento Ambiental , Humanos , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco
10.
Sci Total Environ ; 659: 140-149, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30597464

RESUMO

Eleven major phthalic acid esters (PAEs) congeners were analyzed for PM2.5 samples collected at Mount Tai, a high elevation mountain site in northern China from June to August 2015. The results showed that the average concentration of PAEs in PM2.5 was 19.48ngm-3, and bis(2-Ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP) and diisobutyl phthalate (DIBP) were the predominant species in particle-phase, whereas diethyl phthalate (DEP) and dimethyl phthalate (DMP) were the prevailing PAEs in gas-phase. PAE concentrations decreased at the beginning of cloud/fog events, while they increased after the cloud/fog events since the liquid-phase PAEs could be absorbed by solid-phase PAEs. Potential source contribution function (PSCF) analysis and principal component analysis (PCA) revealed that the highest PSCF value of air masses were mainly sourced from southwest of Mount Tai and multiple sources contributed to PAEs. A Monte Carlo simulation was applied to estimate the incremental lifetime cancer risks (ILCR) from inhalation exposure on the basis of DEHP concentrations. The estimated values of ILCR for the general population were lower than the U.S. Environmental Protection Agency threshold, which is 10-6. However, since the local population was exposed to various local emission sources, the actual health risk is undervalued.

11.
Clin Ther ; 39(5): 1040-1051, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28431767

RESUMO

PURPOSE: Our aim was to characterize the newly established new drug conditional approval process in China and discuss the challenges and opportunities with respect to new drug research and development and registration. METHODS: We examined the new approval program through literature review, law analysis, and data analysis. Data were derived from published materials, such as journal articles, government publications, press releases, and news articles, along with statistical data from INSIGHT-China Pharma Databases, the China Food and Drug Administration website, the Center for Drug Evaluation website, the US Food and Drug Administration website, and search results published by Google. FINDINGS: Currently, there is a large backlog of New Drug Applications in China, mainly because of the prolonged review time at the China Food and Drug Administration, resulting in a lag in drug approvals. In 2015, the Chinese government implemented the drug review and registration system reform and tackled this issue through various approaches, such as setting up a drug review fee system, adjusting the drug registration classification, and establishing innovative review pathways, including the conditional approval process. IMPLICATIONS: In Europe and the United States, programs comparable to the conditional approval program in China have been well developed. The conditional approval program recently established in China is an expedited new drug approval process that is expected to affect new drug development at home and abroad and profoundly influence the public health and the pharmaceutical industry in China. Like any program in its initial stage, the conditional approval program is facing several challenges, including setting up a robust system, formatting new drug clinical research requirements, and improving the regulatory agency's function for drug review and approval. The program is expected to evolve and improve as part of the government mandate of the drug registration system reform.


Assuntos
Aprovação de Drogas , China , Indústria Farmacêutica , Órgãos Governamentais , Estados Unidos
12.
Environ Sci Process Impacts ; 15(3): 623-32, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23738361

RESUMO

Inhalatory and dermal exposures of on-duty vehicle inspection workers to polycyclic aromatic hydrocarbons (PAHs) in Beijing were investigated from April 18 to May 17, 2011. Exposure levels to particulate PAHs for the vehicle inspection workers at gasoline, bus and diesel lines were found to be 56.07 ng m(-3), 111.72 ng m(-3) and 199.80 ng m(-3), respectively. A probabilistic risk assessment framework was integrated with the toxic equivalence factors (TEFs) and the incremental lifetime cancer risk (ILCR) approaches to quantitatively estimate the exposure risk for vehicle inspection workers of the three work lines. The median values of inhalation risk were estimated to be 3.7 × 10(-7), 5.0 × 10(-7) and 1.37 × 10(-6), respectively, while the median dermal ILCR values were 7.05 × 10(-6), 6.98 × 10(-6) and 1.28 × 10(-5), respectively for gasoline, bus, and diesel inspection workers. Total ILCR was higher than the acceptable risk level of 10(-6), indicating unacceptable potential cancer risk.


Assuntos
Exposição por Inalação/análise , Neoplasias/etiologia , Exposição Ocupacional/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Monitoramento Ambiental , Humanos , Medição de Risco , Pele/efeitos dos fármacos , Local de Trabalho
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