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1.
Huan Jing Ke Xue ; 42(10): 4889-4896, 2021 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-34581132

RESUMO

Taking the Minhang District of Shanghai as a typical rapidly urbanizing area, and based on 595 soil samples from 36 plots, the content of eight heavy metals in soils from five different land uses were analyzed. The ecological risk was evaluated using the Nemerow composite index and the potential ecological risk index. The results showed that the variation coefficients of the heavy metals Zn and Cd were highest, and were notably affected by human activities. The content of heavy metals in industrial land soil was relatively high compared to residential land and cultivated land soils, and heavy metal content was lowest in public management and service land soil. The Nemerow composite index of Zn and Cd was high, corresponding to severe and moderate levels of pollution, respectively. The other heavy metals were found at warning or light levels of pollution. The potential ecological risks posed by heavy metals in the soils from different land uses, in descending order, were heavy-metal-related industry land > non-heavy-metal-related industry land≈residential land > cultivated land≈public management and service land. Industrial land had a greater risk of heavy metal pollution due to industrial operations, complex historical production, and widely variable levels of management. Heavy metal accumulation also tended to occur in residential land and cultivated land soils. Therefore, the prevention of soil heavy metal pollution in association with different land uses, and the control of associated risks during redevelopment, are key challenges in rapidly urbanizing area.


Assuntos
Metais Pesados , Poluentes do Solo , China , Monitoramento Ambiental , Humanos , Metalurgia , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise
2.
Mater Sci Eng C Mater Biol Appl ; 128: 112266, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474825

RESUMO

The precipitates in Ti-Ag alloy made an important contribution to antibacterial activity. In order to study this specific effects, Ti-Ag samples with different forms of precipitates were produced by powder metallurgy and ingot metallurgy followed by heat treatment: Ti-Ag(T4) with no precipitate, Ti-Ag(as-cast) and Ti-Ag(T6) with Ti2Ag and Ti-Ag(PM) with Ti2Ag and Ag-rich phase. Microstructure was analyzed by scanning electronic microscope (SEM), and the antibacterial effects, expression of reactive oxygen species (ROS), protein leakage and biocompatibility were investigated by plate count method, staining technology and cell test. The antibacterial ability was in the following order from low to high: Ti-Ag(T4) < Ti-Ag(as-cast) < Ti-Ag(T6) < Ti-Ag(PM). It was elucidated that Ag-containing phase was the major controlling factor of Ti-Ag antibacterial property and Ti-Ag(PM) with micro-size Ti2Ag and Ag-rich phase exhibited high antibacterial activity. It was proposed that the existence of Ag-containing phases induced high expression of ROS in bacteria, which destroyed the homeostasis of the bacteria and eventually leads to the rupture of the bacterial membrane. Cell test indicated that Ti-Ag samples had no adverse effect on cells and had good biocompatibility.


Assuntos
Ligas , Staphylococcus aureus , Ligas/farmacologia , Antibacterianos/farmacologia , Teste de Materiais , Metalurgia , Titânio/farmacologia
3.
J Mech Behav Biomed Mater ; 123: 104707, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34352487

RESUMO

The requirements for biomedical materials have been raised greatly due to the rapidly aging global population. Shape memory alloys (SMAs) are indeed promising materials for biomedical applications due to their controllable shape deformation via the manipulation of temperature and/or stress. This study investigated the enhancement of the fundamental mechanical properties and the shape memory effect (SME) in the Ti-Cr-based alloys via the modification of Au and Cu. The quaternary Ti-Cr-Au-Cu alloys were successfully manufactured by physical metallurgy methods and their phase constitutions, mechanical properties, SME, and superelastic (SE) behaviors have been investigated in this study. Cold-workability, which was enhanced by the introduction of the Au element, was elaborated by the phase constitutions of the alloys. The ß-parent phase was stabilized to around body temperature by the introduction of the ß-stabilizers of Cr, Au, and Cu, and the functionalities of the specimens were revealed at the operating temperature. Perfect SME at the shape recovery rate of 100% was practiced by the substitution of Au by Cu and the mechanical properties, such as strength and ductility, were also enhanced. Functional mappings of the fundamental mechanical properties, which could be a helpful tool for the investigations of the quaternary Ti-Cr-Au-Cu alloys, were constructed in this work.


Assuntos
Ligas , Titânio , Materiais Biocompatíveis , Teste de Materiais , Metalurgia , Resistência à Tração
4.
Environ Pollut ; 288: 117593, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34245983

RESUMO

Metallurgical industries remain a considerable source of trace element contamination and potential human health risk. Determination of sources is a key challenge. With respect to the South Pacific's largest and longest operating metallurgic smelter in Nouméa, New Caledonia, determining the environmental impact and subsequent human health risk associated with local ferronickel smelting is complicated by natural geological enrichment of Ni and Cr. This study applies a multi-method and multi-matrix approach to disentangle smelter emissions from geogenic sources and model the consequent health risk from industrial activity. Dust wipes (n = 108), roadside soil (n = 91), garden soil (n = 15) and household vacuum dust (n = 39) were assessed to explore geospatial trace element (As, Cr, Cu, Fe, Mn, Ni, Pb, S, V and Zn) variations across outdoor and indoor environments. Enrichment factors (EF) identified elevated levels of smelter-related trace elements: S (EF = 7), Ni (EF = 6) and Cr (EF = 4), as well as Zn (EF = 4). Smelter-related elements in soil and dust deposits were negatively correlated with distance from the facility. Similarity of Pb isotopic compositions between dust wipes, surface soil and vacuum dust indicated that potentially toxic trace elements are being tracked into homes. Non-carcinogenic health risk modelling (Hazard Index, HI) based on 15 spatial nodes across Nouméa revealed widespread exceedance of tolerable risk for children (0-2 years) for Ni (HI 1.3-15.8) and Mn (HI 0.6-1.8). Risk was greatest near the smelter and to the north-west, in the direction of prevailing wind. Given the elevated cancer risk documented in New Caledonia, disentanglement of environmental from industrial sources warrants further attention to ensure community health protection. Our analysis illustrates how the confounding effects from complex environmental factors can be distilled to improve the accuracy of point source apportionment to direct future mitigation strategies.


Assuntos
Metais Pesados , Oligoelementos , Criança , Poeira/análise , Monitoramento Ambiental , Humanos , Ferro , Metalurgia , Metais Pesados/análise , Níquel , Medição de Risco , Solo , Oligoelementos/análise
5.
Br Dent J ; 231(1): 49-57, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34244648

RESUMO

Since the introduction of nickel-titanium endodontic instruments, there have been a myriad of developments which can be confusing and sometimes contradictory. This article seeks to review and articulate these advances, and allow the reader to better understand the benefits and the limitations of the systems available. Ultimately, this helps clinicians to engage more confidently with trade and have a more informed choice of the most appropriate file to use for each individual endodontic case. All this should facilitate more predictable endodontic outcomes.


Assuntos
Instrumentos Odontológicos , Preparo de Canal Radicular , Ligas Dentárias , Desenho de Equipamento , Metalurgia , Tecnologia , Titânio
6.
Nat Chem ; 13(6): 514-515, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34075216

Assuntos
Metalurgia
7.
J Hazard Mater ; 419: 126415, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34166953

RESUMO

Nonferrous metallurgical processes are important sources of carcinogenic polybrominated dibenzo-p-dioxin and dibenzofuran (PBDD/Fs) that transport globally. Studies on the profiles, spatial distributions and inventory of PBDD/F emissions into the atmosphere from nonferrous metallurgical plants are needed for better source control. In this study, field investigations on PBDD/F emissions from typical nonferrous metallurgical plants were conducted to characterize the PBDD/F profiles and derive their emission factors. Based on the PBDD/F profiles, diagnostic ratios of PBDD/Fs for secondary copper, zinc and lead smelting were proposed for identifying the potential sources of PBDD/Fs in environment. The PBDD/F emission factors for the secondary copper, lead, and zinc smelting plants were 0.71, 1.65, and 1.54 µg toxic equivalents/t, respectively. The estimated annual input of PBDD/Fs into atmosphere by secondary nonferrous metallurgical plants in China was 212.4 g by mass and 3511.3 mg by toxic equivalents, which is of significance for further evolving a global inventory. The spatial distribution of PBDD/F emissions from nonferrous metallurgical plants in China was mapped. Larger amounts of PBDD/Fs were emitted in the southeastern coastal region and northern China than elsewhere in China.


Assuntos
Poluentes Atmosféricos , Dioxinas , Dibenzodioxinas Policloradas , Poluentes Atmosféricos/análise , China , Dioxinas/análise , Monitoramento Ambiental , Furanos , Metalurgia , Dibenzodioxinas Policloradas/análise
8.
J Environ Manage ; 294: 113001, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34111595

RESUMO

Yellow phosphorous flue dust (YPFD) is a solid waste produced by the yellow phosphorus industry that contains heavy metals such as zinc (Zn) and lead (Pb), causing environmental damage. In this work, a vacuum metallurgy method is proposed to separate and recover Zn and Pb from solid waste YPFD. Under optimized conditions of 1173 K, 30 wt% reductant dosage, 60 min, and 5-10 Pa, the pre-separation of Zn and Pb was realized and the recovery rates of Zn and Pb reached 92.47% and 99.78%, respectively. In addition, gallium (Ga) remained in the residue with little loss, and then recovered by raising the reaction temperature to 1323 K. The recovery rates of Ga reached 87.57%. The principle of metal volatilization under vacuum at different temperatures was also clarified. The thermodynamic calculations of the carbothermal reduction reaction of metal oxides under vacuum were carried out. The analysis of the product obtained at 1173 K showed that Zn and Pb mainly existed in the form of elemental or simple compounds. At 1323 K, Ga in the residue was highly enriched in the condensation zone, which is conducive for the subsequent purification. The whole process is short, there is no waste water, low levels of pollution of emitted, and the technology provides a clean and sustainable way to reuse YPFD.


Assuntos
Metais Pesados , Zinco , Poeira , Chumbo , Metalurgia , Metais Pesados/análise , Fósforo , Vácuo , Zinco/análise
9.
Rev Esp Salud Publica ; 952021 Jun 09.
Artigo em Espanhol | MEDLINE | ID: mdl-34103466

RESUMO

BACKGROUND: The analysis of mortality offers an important indicator for assessing the state of workers' occupational health. Workers involved in the extraction, refining, alloying and manufacturing of metals are frequently exposed to occupational risks that can lead to their death. The objective of this work was to synthesize the scientific evidence about factors associated with mortality among workers in the metallurgical industry. METHODS: A bibliographic review was conducted using the PubMed database. Seventeen studies were included, where topics addressed specific problems that influence the mortality of workers in the metallurgical industry sector. Complete texts of the articles were reviewed. RESULTS: Findings show the highest probabilities of death due to malignant neoplasms (48%), diseases of the circulatory system (28%), work accidents (15%), suicide and violence (9%). CONCLUSIONS: Despite the research carried out, there are gaps and limitations in the study of mortality in workers in the metallurgical industry, mainly related to the relationship of the cause of death with occupational risk factors.


Assuntos
Acidentes de Trabalho/mortalidade , Metalurgia , Doenças Profissionais/mortalidade , Humanos , Fatores de Risco , Espanha/epidemiologia
10.
Sci Total Environ ; 788: 147755, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34134385

RESUMO

The analyses of human-environment interactions in prehistoric and medieval mining and metallurgical centres in Europe result in various assessments of the environmental impact of early metal ore mining and metallurgy. In some mining and metallurgical sites or areas, such as the prehistoric basin on the Greek island of Kythnos or the later Morvan and Mont Lozère areas in France as well as Tjursbosjön in Sweden, the impact was significant and lasting. In others, such as: Cors Fochno in Wales, the Falkenstein region in Austria, or the Northern Vosges Mountains in France, the environmental changes were limited and reversible. The results of palaeobotanical research (pollen analysis and analysis of plant macroremains) in peat cores from southern Poland enabled the Holocene vegetation transformations in one of the oldest mining regions in Central Europe to be reconstructed. They also provided new data, used to assess the impact of settlements as well as the development of metallurgy on the environment in the region and changes in bog ecosystems. The first changes in vegetation caused by human activity were observed at the boundary between the Neolithic and Bronze Ages. They are documented by pollen indicating shepherding activity and single grains of cereal pollen. The greatest intensity of change, reflected in sediment as a maximum concentration of charcoal, was recorded at the end of the Bronze Age and attributed to the Lusatian culture. The changes in the vegetation under the impact of human activity until the early Middle Ages were reversible and had a local scope. The intensification of slash-and-burn agriculture was indicated as the most probable and important cause.


Assuntos
Rios , Áreas Alagadas , Áustria , Ecossistema , Europa (Continente) , França , Humanos , Metalurgia , Polônia , Suécia , País de Gales
11.
Sci Total Environ ; 790: 147986, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34090162

RESUMO

Trace element concentrations in the Cartagena Bay coastal record reveal a contribution of natural processes. However, the influence of anthropogenic factors predominates in the last three millennia, particularly aerosol deposition linked to mining and industrial activities in the area. The coastal record of Cartagena can be considered a preserved environment, suitable to search for regional human activity fingerprinting, specifically that related to the deposition of heavy metals such as Pb and Cu. A multivariate statistical analysis was carried out to clarify the geochemical behaviour of trace and major elements. Our study design represents a novel approach to assign natural contributions, such as eolian and riverine input, to coastal deposits, and organic matter preservation under anoxic environments. Therefore, synergies obtained by the simultaneous study of multivariate statistics and enrichment factors allow robust conclusions about palaeoenvironmental evolution and human activities. Anthropogenic influence suggested that Pb mining and metallurgy began during the Chalcolithic period, with considerable inputs of Pb and Cu to atmospheric pollution during Phoenician, Punic and Roman times.


Assuntos
Metais Pesados , Oligoelementos , Monitoramento Ambiental , Humanos , Metalurgia , Metais Pesados/análise , Mineração , Oligoelementos/análise
12.
Artigo em Inglês | MEDLINE | ID: mdl-34072057

RESUMO

Industrial waste discharged by heavy pollution industry is one of the main causes of global environmental degradation. Research on the environmental efficiency of high-polluting industry is necessary to tackle the problem of global environmental pollution. Using panel data of 19 sub-industries in China's heavy pollution industry from 2001 to 2015, this article employs Data Envelopment Analysis (DEA) and Malmquist index (MI) to measure the environmental efficiency of heavy pollution industry from both the dynamic and static perspectives. The results show that the environmental efficiency of China's heavy pollution industry maintains an upward trend but did not reach the optimal level. The general trend shows a phased trend of increasing first and then decreasing. Besides, there are inter-industry differences in the environmental efficiency across the examined sub-industries. Based on the research findings, this article proposes a set of corresponding countermeasures to solve the global pollution problem, such as reducing energy inputs and minimizing the volumes of the main categories of emissions in high-polluting industry, as well as improving the production management in the group of high environmental efficiency and strengthening technical capabilities in the group of low environmental efficiency.


Assuntos
Eficiência , Poluição Ambiental , China , Análise de Dados , Resíduos Industriais , Metalurgia
13.
Ecotoxicol Environ Saf ; 219: 112321, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33991933

RESUMO

Slag tailings are produced by "cooling-grinding-ball milling-flotation" and other processes of slag, while slag is produced by the flash smelting of the original ore. The utilization and environmental hazards of arsenic in slag tailings have become a focus of attention. This study on slag tailings reveals the presence of arsenic in copper smelting tailings from the mineralogy and leaching perspectives, and the noncarcinogenic and carcinogenic risks of arsenic to the human body were assessed by using the USEPA health risk model. The surface particles of the slag tailings were unevenly dispersed, and the mineral crystals were relatively complete. A small amount of secondary minerals had grown on the mineral surface. Most of the fine particles adhered to the surface of the main mineral to form inclusions. The mineral composition of the slag tailings was dominated by maghemite (Fe3O4) and fayalite (Fe2SiO4), and the arsenic-bearing minerals were unevenly distributed, where As (Ⅴ) fine particles were embedded in maghemite, amorphous phase and fayalite. There was a large amount of residual arsenic in the slag tailing particles, and the leaching content of arsenic in the toxicity leaching procedure was always lower than the limit of 5 mg/L. The health risk to the exposed population was evaluated by the USEPA health risk model. Since the exposed population in the industrial land is mainly adults, it is determined that the tailings will not cause harm to children's health. In this evaluation, the exposure duration (length of service of the workers) of 30 years, exposure frequency of 314 d/y and body weight of 60 kg (average weight of the workers) were taken as the parameters of three exposure pathways: hand-oral ingestion, respiratory system inhalation and skin contact. Therefore, longer activity time of the workers in the tailing workshop corresponds to a higher HI (hazard index). Although the arsenic in the slag tailings had a certain degree of bioavailability, it was not sufficient to adversely affect human health.


Assuntos
Arsênio/toxicidade , Cobre , Exposição Ambiental/estatística & dados numéricos , Arsênio/análise , Arsênio/química , Humanos , Metalurgia , Minerais , Medição de Risco
14.
Artigo em Inglês | MEDLINE | ID: mdl-33952112

RESUMO

The scope of this work is the evaluation of the non-carcinogenic occupational risk related to foundry emissions, focusing on the category of workers involved in olfactometric assessments. Odor pollution from industrial activities such as foundries is a serious environmental concern. Sensorial techniques (e.g. dynamic olfactometry, EN13725:2003) currently represent the preferred method for odor emission characterization. During olfactometric analyses, human assessors are directly exposed to the odor at increasing concentrations, thus requiring the assessment of the associated exposure risk to guarantee workers' safety. This paper presents an investigation aiming to produce an inventory of compounds emitted from foundries together with their odor thresholds and toxicological limits (TLVs), with the final objective to propose a procedure for ensuring workers' safety during olfactometric analyses. Looking at the database resulting from this study, among the >100 compounds emitted by foundries, 8 have a maximum concentration above their TLV. Among those, ammonia, H2S, phenol, toluene and trimethylamine, produce an odor stimulus before they reach a toxic concentration, thus not representing a risk for olfactometric workers. Benzene, formaldehyde and SO2 are identified as the most critical compounds because they may reach toxic concentrations in foundry emissions, and they start being perceived by humans above their TLV. The proposed procedure entails a minimum dilution factor of 27'000 to be applied to odor samples analyzed by olfactometry, which however might result inapplicable in practical cases, thus pointing out the necessity to adopt chemical measurements to investigate specifically the concentration of the most critical compounds identified in this study.


Assuntos
Exposição Ocupacional/análise , Odorantes/análise , Olfatometria/métodos , Poluentes Atmosféricos/análise , Formaldeído/análise , Humanos , Metalurgia , Tolueno/análise
15.
Workplace Health Saf ; 69(9): 423-434, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33896275

RESUMO

BACKGROUND: Coal miners have been reported to have higher rates of risky/harmful alcohol misuse; however, it is not known if metalliferous mining employees whose working conditions differ in workplace practices, also have increased rates of risky/harmful alcohol misuse. This study aimed to examine alcohol consumption in a sample of Australian metalliferous mining workers and to examine the demographic and workplace factors associated with risky/harmful alcohol use. METHODS: All employees from a convenience sample of four Australian mine sites were invited to complete a paper-based cross-sectional survey between June 2015 and May 2017. The survey contained questions relating to social networks, health behaviors, psychological distress, demographic characteristics, and risky/harmful drinking. Current alcohol use was measured by the Alcohol Use Disorders Identification Test (AUDIT), a validated measure of risky and/or harmful drinking. Factors associated with risky/harmful drinking were investigated using univariate and multivariable logistic regression. FINDINGS: A total of 1,799 participants completed the survey (average site response rate 95%). Overall, 94.8% of males and 92.1% of females reported using alcohol in the preceding 12 months. The odds of risky/harmful alcohol use were significantly higher in those who were male, younger, and reported higher psychological distress. CONCLUSIONS/APPLICATION TO PRACTICE: This study identified that metalliferous mining employees engage in at-risk levels of alcohol consumption significantly higher than the national average despite workplace policies and practices that restrict alcohol use. Personal and workplace risk factors that may help target specific employee groups and inform the development of tailored, integrated multicomponent intervention strategies for the industry were identified.


Assuntos
Consumo de Bebidas Alcoólicas/psicologia , Metalurgia/estatística & dados numéricos , Mineradores/estatística & dados numéricos , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , Austrália , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Masculino , Metalurgia/organização & administração , Pessoa de Meia-Idade , Mineradores/psicologia , Fatores de Risco , Inquéritos e Questionários
16.
PLoS One ; 16(3): e0247051, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33657163

RESUMO

An in-depth study on the characteristics of coke in the hearths of blast furnaces is of great significance for explaining the mechanism of coke deterioration in blast furnaces. In the present work, the changes in macromorphology, degree of graphitization, and microstructure of the coke taken from different hearth locations of a 5,800 m3 superlarge blast furnace during its intermediate repair period were systematically studied. Significant differences were found between cokes obtained from the edge ("edge coke") and from the center ("center coke") of the hearth in terms of properties and degradation mechanisms. Edge coke was severely eroded by liquid metal, and only a small amount of slag was detected in the coke porosity, whereas center coke was basically free from erosion by liquid metal, and a large amount of slag was detected in the coke porosity. The degree of graphitization of edge coke was higher than that of center coke. The carburizing effect of liquid metal was the main cause of the degradation of edge coke and made it smaller or even disappear. Center coke was degraded due to the combination of two factors: slag inserted into micropores on the surface of center coke loosened the surface structure; and graphite-like flakes that appeared on the center coke surface lowered the strength and caused cracks in the surface.


Assuntos
Coque/análise , Grafite/análise , China , Metalurgia , Microscopia Eletrônica de Varredura , Microscopia de Polarização , Tamanho da Partícula , Difração de Raios X
17.
Environ Res ; 197: 111050, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33753074

RESUMO

This paper presents the latest overview of the environmental impact of wastes from the non-ferrous metallurgical industry. Ashes, slags and dusts - by-products from mining and metal processing - are sources of toxic metals, such as Pb, Cd, Hg, As, Al, as well as particulate matter. Physical, chemical and biological processes transform industrial wastes and cause water, soil and air pollution. Improperly protected heaps are subject to wind erosion and rain water leaching. Heavy metals and particulate matter are transported over long distances, contaminating the soil, living areas, watercourses, while in combination with mist they create smog. Water erosion releases heavy metals, which are leached into groundwater or surface runoff. This paper focuses on the range of pollution emissions from non-ferrous metallurgy wastes, hazards, mechanisms of their formation and fallouts, on the current state of technology and technological risk reduction solutions. The impact of pollution on human health and the biosphere, and methods of waste reduction in this industry sector are also presented. A sustainable and modern mining industry is the first step to cleaner production.


Assuntos
Metais Pesados , Poluentes do Solo , Cobre , Monitoramento Ambiental , Poluição Ambiental , Humanos , Resíduos Industriais/análise , Metalurgia , Metais Pesados/análise , Mineração , Poluentes do Solo/análise
18.
Environ Health ; 20(1): 27, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33722243

RESUMO

BACKGROUND: Exposure to occupational manganese (Mn) is associated with neurotoxic brain injury, manifesting primarily as parkinsonism. The association between environmental Mn exposure and parkinsonism is unclear. To characterize the association between environmental Mn exposure and parkinsonism, we performed population-based sampling of residents older than 40 in Meyerton, South Africa (N = 621) in residential settlements adjacent to a large Mn smelter and in a comparable non-exposed settlement in Ethembalethu, South Africa (N = 95) in 2016-2020. METHODS: A movement disorders specialist examined all participants using the Unified Parkinson Disease Rating Scale motor subsection part 3 (UPDRS3). Participants also completed an accelerometry-based kinematic test and a grooved pegboard test. We compared performance on the UPDRS3, grooved pegboard, and the accelerometry-based kinematic test between the settlements using linear regression, adjusting for covariates. We also measured airborne PM2.5-Mn in the study settlements. RESULTS: Mean PM2.5-Mn concentration at a long-term fixed site in Meyerton was 203 ng/m3 in 2016-2017 - approximately double that measured at two other neighborhoods in Meyerton. The mean Mn concentration in Ethembalethu was ~ 20 times lower than that of the long-term Meyerton site. UPDRS3 scores were 6.6 (CI 5.2, 7.9) points higher in Meyerton than Ethembalethu residents. Mean angular velocity for finger-tapping on the accelerometry-based kinematic test was slower in Meyerton than Ethembalethu residents [dominant hand 74.9 (CI 48.7, 101.2) and non-dominant hand 82.6 (CI 55.2, 110.1) degrees/second slower]. Similarly, Meyerton residents took longer to complete the grooved pegboard, especially for the non-dominant hand (6.9, CI -2.6, 16.3 s longer). CONCLUSIONS: Environmental airborne Mn exposures at levels substantially lower than current occupational exposure thresholds in the United States may be associated with clinical parkinsonism.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Exposição Ambiental/efeitos adversos , Manganês/toxicidade , Transtornos Parkinsonianos/induzido quimicamente , Acelerometria , Adolescente , Adulto , Idoso , Poluentes Ocupacionais do Ar/análise , Fenômenos Biomecânicos , Criança , Pré-Escolar , Exposição Ambiental/análise , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Manganês/análise , Testes de Estado Mental e Demência , Metalurgia , Pessoa de Meia-Idade , Transtornos Parkinsonianos/fisiopatologia , Material Particulado/análise , Material Particulado/toxicidade , África do Sul , Adulto Jovem
20.
Arch Environ Contam Toxicol ; 80(3): 546-557, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33755741

RESUMO

The active moss biomonitoring technique was applied to assess the environmental pollution in the Donetsk region and to compare the biomonitoring capacity of acrocarpous (Ceratodon purpureus) and pleurocarpous (Brachythecium campestre) moss transplants. Moss bags were exposed for 6 months in the surroundings of two steelworks, a power station, and two parks. The concentrations of 19 elements were determined in the moss transplants by neutron activation analysis and atomic absorption spectrometry. Various environmental indices-relative accumulation factor, contamination factor, pollution load index, enrichment factor, and ecological risk index-were used to quantitatively assess the degree of ambient contamination. The RAF values indicate that the most prevalent elements in Brachythecium campestre and Ceratodon purpureus were Na, Al, Ca, Fe, Ti, V, Cr, Mn, Co, Ni, Zn, Ba, Sr, Pd, and Cd. The results showed a significant difference between metal accumulation by Ceratodon purpureus and Brachythecium campestre indicating various mechanisms of uptake. All elements were highly correlated in Ceratodon purpureus. The main air pollution sources in the region are the Zuivska power station (Zuivska TES), Donetsk Metallurgical Plant, and Yenakiieve Iron and Steel Works.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Briófitas , Metais Pesados , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Biológico , Monitoramento Ambiental , Metalurgia , Metais Pesados/análise , Ucrânia
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