Regulations Concerning Naturally Occurring Asbestos (NOA) in Germany—Testing Procedures for Asbestos

2020 ◽  
Vol 26 (1) ◽  
pp. 67-71
Author(s):  
Stefan Pierdzig
Keyword(s):  
Size Fraction ◽  
Hazardous Substances ◽  
World Health ◽  
Fiber Concentration ◽  
Worst Case ◽  
Testing Procedures ◽  
Industrial Sectors ◽  
Naturally Occurring ◽  
Workplace Monitoring ◽  
Naturally Occurring Asbestos

ABSTRACT In Germany, potential asbestos-containing rocks are used as raw materials for a number of engineering applications. These rocks are ultrabasites (dunite, harzburgite), igneous rocks (basalt, gabbro, norite), and metasomatic or metamorphic rocks like talcum, greenschist and amphibolite. Based on the German Gefahrstoffverordung (Hazardous Substances Ordinance), regulatory statutes exist for operations using these rocks and resultant composites and products. The authorities state that in Germany no natural rocks exist with more than 0.1 mass-% of one of the six regulated asbestos minerals. But it is well known that there are rocks with a high modal concentration of these minerals with a non-asbestiform, columnar to prismatic habitus. Under mechanical stress during handling, they can lead to fibrous cleavage fragments, which conform to the World Health Organization (WHO) “respirable asbestos fiber” definition. In view of this fact, the regulations changed in 2009, with revision of the Technical Rules for Hazardous Substances (TRGS) 517: any fibrous asbestos particles, regardless of whether or not they represent naturally occurring asbestos or are of cleavage origin, are evaluated for potential hazards associated with handling of these rocks. If the WHO fiber concentration is <0.1 mass-%, rocks and products can be used and re-used under protective measures. At concentrations >0.1 mass-%, the material is considered hazardous waste. These regulations apply to many industrial sectors that exploit and process rocks, using them in road building and track construction and when they are recycled. Analysis (by scanning electron microscopy, SEM/energy dispersive x-ray spectroscopy, EDS) to determine the asbestos concentration of rocks, gravels, or dusts is carried out in the <100-µm, grain-size fraction produced by sieving or grinding. The results provide a representation of a worst-case examination of the air quality during mechanical treatment of these materials. Workplace monitoring is done by air sampling to survey an exposure limit of 10,000 fibers/m3 of air (0.01 f/cc).

Naturally Occurring Asbestos in Valmalenco (Central Alps, Northern Italy): From Quarries and Mines to Stream Sediments

2020 ◽  
Vol 26 (1) ◽  
pp. 47-52
Author(s):  
Alessandro Cavallo ◽  
Jasmine Rita Petriglieri
Keyword(s):  
Electron Microscopy ◽  
Stream Sediments ◽  
Northern Italy ◽  
World Health ◽  
Central Alps ◽  
Representative Sampling ◽  
Naturally Occurring ◽  
Critical Issues ◽  
Naturally Occurring Asbestos ◽  
Health Organization

ABSTRACT The Valmalenco area (central Alps, northern Italy) is an excellent case study for naturally occurring asbestos (NOA) because of the huge outcrops of serpentinites and widespread quarrying and mining activities. Extensive sampling of rocks, soils, stream sediments, and airborne asbestos has been in progress since 2004. The combined use of scanning electron microscopy and transmission electron microscopy has proven to be effective for the correct discrimination between asbestiform and non-asbestiform mineralogical varieties (but falling into the World Health Organization fiber definition), whereas phase contrast microscopy has not proven suitable because of the very small size of fibrils after strong mechanical fragmentation. The quantitative analysis of “massive” samples (rocks, soils, and sediments) requires accurate and representative sampling as well as specific counting and discrimination criteria to determine NOA. Over a decade of experience has allowed us to identify critical issues and adopt effective preventive measures.

Phytoconstituents in the Management of Covid-19: Demystifying the Fact

Drug Research ◽  
2022 ◽  
Author(s):  
Md. Abul Barkat ◽  
Pawan Kaushik ◽  
Harshita Abul Barkat ◽  
Mohammad Idreesh Khan ◽  
Hazrina Ab Hadi
Keyword(s):  
Therapeutic Agent ◽  
Clinical Development ◽  
World Health ◽  
Therapeutic Drug ◽  
Scientific Communities ◽  
Synthetic Drugs ◽  
Naturally Occurring ◽  
Deadly Disease ◽  
Novel Coronavirus ◽  
Health Organization

AbstractThe 2019-nCoV (COVID-19; novel coronavirus disease-2019) outbreak is caused by the coronavirus, and its continued spread is responsible for increasing deaths, social and economic burden. COVID-19 created a chaotic situation worldwide and claimed the lives of over 5,027,183 and 248,467,363 confirmed cases have been reported so far as per the data published by WHO (World Health Organization) till 5th November 2021. Scientific communities all over the world are toiling to find a suitable therapeutic drug for this deadly disease. Although till date no promising drug has been discovered for this COVID-19. However, as per the WHO, over 102 COVID-19 vaccines are in clinical development and 185 in pre-clinical development. Naturally occurring phytoconstituents possess considerable chemical richness in the form of anti-viral and anti-parasitic potential and have been extensively exploited for the same globally. Still, phytomedicine-based therapies are considered as the best available treatment option to minimize and treat the symptoms of COVID-19 because of the least possible side effects compared to synthetic drugs recommended by the physicians/clinicians. In this review, the use of plant chemicals as a possible therapeutic agent for severe acute respiratory syndrome coronavirus 2 (SARS CoV2) is highlighted with their proposed mechanism of action, which will prove fruitful and effective in finding a cure for this deadly disease.

scholarly journals Impact of Naturally Occurring Asbestos on Asbestos Ban: Regulations and Experience of the Republic of Korea

2022 ◽  
Vol 19 (2) ◽  
pp. 742
Author(s):  
Jiwoon Kwon
Keyword(s):  
Preventive Measures ◽  
Control Measures ◽  
Exposure Risk ◽  
Close Collaboration ◽  
Mineral Particles ◽  
Naturally Occurring ◽  
Transmission Electron ◽  
The Future ◽  
Naturally Occurring Asbestos ◽  
The Republic

This review examined the main issues debated in Korea regarding the production and use of materials containing naturally occurring asbestos (NOA) as impurities, and investigated the impacts of these debates on the asbestos ban, as well as the future implications. In Korea, incidents associated with the production and use of NOA-contaminated talc powders, construction rocks, serpentinites, and dolomite rocks raised public concern and led to accelerating the ban on asbestos. The main controversies concern policies on appropriate asbestos content limits, whether materials containing a trace amount of NOA should be banned, and the control of materials with high human exposure risk. To address recurring controversies, the implementation of preventive measures to manage elongated mineral particles and the use of transmission electron microscopy for more sensitive analysis need to be discussed, along with reaching social agreement on the controversial policies. To minimize the potential exposure to asbestos that may occur during the production and use of industrial minerals in the future, it is necessary to apply occupational exposure control measures and monitor the health effects of the relevant population groups. These national policies on NOA should be prepared based on close collaboration and discussion with policymakers, industry stakeholders, and related academic experts.

scholarly journals Wildfire air pollution hazard during the 21st century

2017 ◽  
Vol 17 (14) ◽  
pp. 9223-9236 ◽  
Author(s):  
Wolfgang Knorr ◽  
Frank Dentener ◽  
Jean-François Lamarque ◽  
Leiwen Jiang ◽  
Almut Arneth
Keyword(s):  
Climate Change ◽  
Air Pollution ◽  
Significant Risk ◽  
Air Pollutant ◽  
Pollutant Emissions ◽  
Anthropogenic Sources ◽  
World Health ◽  
Fire Season ◽  
Worst Case ◽  
The World

Abstract. Wildfires pose a significant risk to human livelihoods and are a substantial health hazard due to emissions of toxic smoke. Previous studies have shown that climate change, increasing atmospheric CO2, and human demographic dynamics can lead to substantially altered wildfire risk in the future, with fire activity increasing in some regions and decreasing in others. The present study re-examines these results from the perspective of air pollution risk, focussing on emissions of airborne particulate matter (PM2. 5), combining an existing ensemble of simulations using a coupled fire–dynamic vegetation model with current observation-based estimates of wildfire emissions and simulations with a chemical transport model. Currently, wildfire PM2. 5 emissions exceed those from anthropogenic sources in large parts of the world. We further analyse two extreme sets of future wildfire emissions in a socio-economic, demographic climate change context and compare them to anthropogenic emission scenarios reflecting current and ambitious air pollution legislation. In most regions of the world, ambitious reductions of anthropogenic air pollutant emissions have the potential to limit mean annual pollutant PM2. 5 levels to comply with World Health Organization (WHO) air quality guidelines for PM2. 5. Worst-case future wildfire emissions are not likely to interfere with these annual goals, largely due to fire seasonality, as well as a tendency of wildfire sources to be situated in areas of intermediate population density, as opposed to anthropogenic sources that tend to be highest at the highest population densities. However, during the high-fire season, we find many regions where future PM2. 5 pollution levels can reach dangerous levels even for a scenario of aggressive reduction of anthropogenic emissions.

Overview of Naturally Occurring Asbestos in California and Southwestern Nevada

2020 ◽  
Vol 26 (1) ◽  
pp. 9-14
Author(s):  
R. Mark Bailey
Keyword(s):  
Sierra Nevada ◽  
North American ◽  
Volcanic Belt ◽  
Island Arc ◽  
North American Plate ◽  
Mountain Range ◽  
The North ◽  
Rock Types ◽  
Naturally Occurring ◽  
Naturally Occurring Asbestos

ABSTRACT Naturally occurring asbestos (NOA) is being discovered in a widening array of geologic environments. The complex geology of the state of California is an excellent example of the variety of geologic environments and rock types that contain NOA. Notably, the majority of California rocks were emplaced during a continental collision of eastward-subducting oceanic and island arc terranes (Pacific and Farallon plates) with the westward continental margin of the North American plate between 65 and 150 MY BP. This collision and accompanying accretion of oceanic and island arc material from the Pacific plate onto the North American plate, as well as the thermal events caused by emplacement of the large volcanic belt that became today's Sierra Nevada mountain range, are the principal processes that produced the rocks where the majority of NOA-bearing units have been identified.

Naturally occurring asbestos in an alpine ophiolitic complex (northern Corsica, France)

2019 ◽  
Vol 78 (17) ◽  
Author(s):  
Didier Lahondère ◽  
Florence Cagnard ◽  
Guillaume Wille ◽  
Jéromine Duron
Keyword(s):  
Naturally Occurring ◽  
Naturally Occurring Asbestos ◽  
Ophiolitic Complex

A New Tolerance Analysis Method for Designers and Manufacturers

1987 ◽  
Vol 109 (2) ◽  
pp. 112-116 ◽  
Author(s):  
W. H. Greenwood ◽  
K. W. Chase
Keyword(s):  
Tolerance Analysis ◽  
New Method ◽  
Analysis Method ◽  
Worst Case ◽  
Assembly Tolerance ◽  
Naturally Occurring ◽  
Methods Of Analysis

Even when all manufactured parts for an assembly are produced within limits, these parts still may not assemble properly if the assembly tolerance analysis was inadequately performed. Naturally occurring shifts in a process can produce biased distributions which can result in increased assembly problems and a greater number of rejects than anticipated. The most common methods of analysis of assembly tolerance buildup are worst case and root sum squares. The limitations of each of these methods are discussed and a simple new method is proposed which accounts for expected bias. This new method includes both worst case and root sum squares as extreme cases.

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