#polycyclic aromatic compounds

[whats-in-a-sentence]

Figure 14.16 shows ranges of KOW values for various classes of (usually synthetic) organic compounds.

"Environmental Chemistry: A Global Perspective", 4e - Gary W. VanLoon & Stephen J. Duffy

[allthecanadianpolitics]

The polluted water leaching from four massive open-pit coal mines in southern B.C.’s Elk Valley is well documented — fish-killing selenium, sulphates and nitrates that travel downstream into international watersheds along the U.S. border. Add to those boundary-hopping hazards one more contaminant that is airborne. An Alberta study recently published in Environmental Science & Technology Letters highlights the transport of toxic coal dust downwind over the Rocky Mountains into southern Alberta’s watersheds and communities. The study, conducted by researchers with the Alberta government and University of Alberta, sampled blackened snowpacks three kilometres to 60 kilometres downwind of Teck Resources’ mine sites over two winter periods in 2022 and 2023. After melting the dirty snow and assessing its chemical composition, they found vast quantities of polycyclic aromatic compounds, or PACs, a toxic class of organic contaminants.

Continue Reading

Tagging: @newsfromstolenland, @abpoli

[netmassimo]

A new image captured by the James Webb Space Telescope reveals new details of a protostar forming within the molecular cloud cataloged as L1527. The MIRI instrument offered new information on the ongoing processes that are leading to the birth of a new star. An accretion disk is barely visible edge-on and is important because the protostar is still absorbing materials from it and planets could form within it in the future. During its formation, the protostar emits jets of gas that collide with the remains of the surrounding cloud, generating the structures MIRI sees in a color that is blue in the top image (NASA, ESA, CSA, STScI) thanks to the presence of polycyclic aromatic hydrocarbons (PAHs), compounds that are common in space.

[thefactcollector]

Did you know space smells metallic? Astronauts have reported their spacesuits smell like welding fumes when they come back from a space walk.

"...thought to be due to the presence of polycyclic aromatic hydrocarbons, compounds that form in the dust and debris of space." - science.howstuffworks.com

"The Rosetta spacecraft also detected compounds responsible for the smell of rotten eggs, bitter almonds and cat urine, boiling off from the surface of comet 67P/Churyumov-Gerasimenko." - sciencefocus.com

[kingdrawcse]

One of the Molecule Stars, "Sulflower"

"Sulflower," a fusion of 'sulfur' and 'flower,' boasts a sunflower-like structure. In 2006, Moscow State University synthesized this novel compound, the first fully sulfur-substituted polycyclic aromatic hydrocarbon, with a planar structure and D8h symmetry. Fast forward to 2016, Dresden University of Technology's researchers created the second generation Sulflower (J. Am. Chem. Soc. 2017, DOI: 10.1021/jacs.6b12630), earning it a spot among the American Chemical Society's 'C& En News' magazine's 2017 'Molecules of the Year.'

[spacetimewithstuartgary]

Astronomers Discover New Building Blocks of Complex Organic Matter

CfA scientists help detect a new molecule in interstellar space as list of identified complex molecules grows

The element carbon is a building block for life, both on Earth and potentially elsewhere in the vast reaches of space. There should be a lot of carbon in space, but surprisingly, it's not always easy to find. 

While it can be observed in many places, it doesn’t add up to the volume astronomers would expect to see. The discovery of a new, complex molecule (1-cyanopyrene), challenges expectations about where the building blocks for carbon are found and how they evolve. 

Astronomers have long understood that certain carbon-rich stars are soot factories that release copious quantities of small molecular sheets of carbon into the interstellar medium. Scientists thought, however, that these types of carbon-rich molecules could neither survive the harsh conditions of interstellar space nor be re-formed there by combustion-like chemistry because the temperature is far too low.

Researchers from the Center for Astrophysics | Harvard & Smithsonian (CfA) helped lead this research. A paper describing these results was published today in the journal Science. 

“Our detection of 1-cyanopyrene gives us important new information about the chemical origin and fate of carbon -- the single most important element to complex chemistry both on Earth and in space,” said Bryan Changala of the CfA, a co-author of the Science paper. 

The 1-cyanopyrene molecule is made up of multiple fused benzene rings. It belongs to a class of compounds known as Polycyclic Aromatic Hydrocarbons (PAHs), which were previously believed to form only at high temperatures in regions with lots of energy, like the environments surrounding aging stars. On Earth, PAHs are found in burning fossil fuels, and as char marks on grilled food. 

Astronomers study PAHs not just to learn about their particular lifecycle, but to learn more about how they interact with and reveal more about the interstellar medium (ISM) and celestial bodies around them. PAHs are believed to be responsible for the unidentified infrared bands observed in many astronomical objects. These bands arise from the infrared fluorescence of PAHs after they absorb ultraviolet (UV) photons from stars. The intensity of these bands reveal PAHs could account for a significant fraction of carbon in the ISM. 

However, the newly observed 1-cyanopyrene molecules were found in Taurus Molecular Cloud-1 (TMC-1), a cold interstellar cloud. Located in the Taurus constellation, TMC-1 has not yet begun forming stars, and the temperature is only about 10 degrees above absolute zero.

“TMC-1 is a natural laboratory for studying these molecules that go on to form the building blocks of stars and planets,” said Gabi Wenzel, a postdoctoral fellow at the Massachusetts Institute of Technology who led the lab work and is the first author on the Science paper.

“These are the largest molecules we’ve found in TMC-1 to date. This discovery pushes the boundaries of our understanding of the complexity of molecules that can exist in interstellar space,” said co-author Brett McGuire, an Assistant Professor of Chemistry at MIT and an adjunct astronomer at the National Science Foundation (NSF) National Radio Astronomy Observatory (NRAO).

Astronomers used the NSF Green Bank Telescope, the largest fully steerable radio telescope in the world, to discover 1-cyanopyrene. Every molecule has a unique rotational spectrum, like a fingerprint, which allows for its identification. However, their large size and lack of a permanent dipole moment, can make some PAHs difficult – or even impossible – to detect. The observations of cyanopyrene can provide indirect evidence for the presence of even larger and more complex molecules in future observations. 

“Identifying the unique rotational spectrum of 1-cyanopyrene required the work of an interdisciplinary scientific team,” explains co-author Harshal Gupta, NSF Program Director for the Green Bank Observatory and Research Associate at the CfA. “This discovery is a great illustration of synthetic chemists, spectroscopists, astronomers, and modelers working closely and harmoniously.”

This research combined the expertise of astronomy and chemistry with measurements and analysis conducted in the molecular spectroscopy laboratory of Dr. Michael McCarthy at the CfA. 

“The microwave spectrometers developed at the CfA are unique, world-class instruments specifically designed to measure the precise radio fingerprints of complex molecules like 1-cyanopyrene,” said McCarthy. “Predictions from even the most advanced quantum chemical theories are still thousands of times less accurate than what is needed to identify these molecules in space with radio telescopes, so experiments in laboratories like ours are indispensable to these ground-breaking astronomical discoveries."

IMAGE: CfA scientists help detect a new molecule in interstellar space as list of identified complex molecules grows Credit: NSF/NSF NRAO/AUI/S. Dagnello

[larimar]

gettyimages

In celebration of the one year anniversary of NASA's James Webb Space Telescope, NASA has released this image looking at the early formation of stars in the Rho Ophiuchi cloud complex. ⁠ ⁠ This image reveals the Rho Ophiuchi cloud complex, the closest star-forming region to Earth on July 12, 2023. The young stars at the center of many of these disks are similar in mass to the Sun, or smaller. The heftiest in this image is the star S1, which appears amid a glowing cave it is carving out with its stellar winds in the lower half of the image. The lighter-colored gas surrounding S1 consists of polycyclic aromatic hydrocarbons, a family of carbon-based molecules that are among the most common compounds found in space. ⁠ ⁠ These images are a composite of separate exposures acquired by the James Webb Space Telescope using the NIRCam instrument. Several filters were used to sample wide and narrow wavelength ranges. The color results from assigning different hues (colors) to each monochromatic (grayscale) image associated with an individual filter. I July 12, 2023 I 📷️: @nasa @nasawebb + ESA + CSA + STScI #GettyImagesNews

[materialsscienceandengineering]

Can biosurfactants increase microbiological oil degradation in North Sea seawater? An international research team from the universities of Stuttgart und Tübingen, together with the China West Normal University and the University of Georgia, have been exploring this question and the results have revealed the potential for a more effective and environmentally friendly oil spill response. Oil leaks into the oceans are estimated at approximately 1500 million liters annually worldwide. This leads to globally significant environmental pollution, as oil contains hazardous compounds such as polycyclic aromatic hydrocarbons that can have toxic or mutagenic effects on organisms. Oil spills, particularly catastrophic ones resulting in the rapid release of large quantities of oil into the oceans, such as tanker accidents or incidents at oil drilling platforms like Deepwater Horizon in 2010, are especially devastating. In such oil spill incidents, large quantities of chemical dispersants, ranging in the millions of liters depending on the amount of oil, are routinely applied to dissolve oil slicks, prevent oil from reaching coastlines, and enhance oil dispersion in the water. The hope is that microbial oil degradation will be enhanced as a result. This is because special microorganisms that are widespread in nature can feed on crude oil components and break them down into harmless substances. This special ability of microbes naturally cleans oil-contaminated areas.

Read more.

[covenawhite66]

The Winchcombe meteorite not only contains organic materials but also appears to represent a new class of meteorites. It contains low amino acid abundance for a carbonaceous chondrite but unusual ratios among the amino acids and PAHs that are present. Winchcombe one of the first 40 meteorites whose origins within the asteroid belt could be traced.

Abstract

The rapid recovery of the Winchcombe meteorite offers a valuable opportunity to study the soluble organic matter (SOM) profile in pristine carbonaceous astromaterials. Our interests in the biologically relevant molecules, amino acids—monomers of protein, and the most prevalent meteoritic organics—polycyclic aromatic hydrocarbons (PAHs) are addressed by analyzing the solvent extracts of a Winchcombe meteorite stone using gas chromatography mass spectrometry. The Winchcombe sample contains an amino acid abundance of ~1132 parts-per-billion that is about 10 times lower than other CM2 meteorites. The detection of terrestrially rare amino acids, including α-aminoisobutyric acid (AIB); isovaline; β-alanine; α-, β-, and γ-amino-n-butyric acids; and 5-aminopentanoic acid, and the racemic enantiomeric ratios (D/L 

[tameblog]

As Los Angeles battles recent wildfires, air quality across the region has plummeted to hazardous levels. Based on authoritative recommendations, many have turned to air filters and purifiers as a defense against smoke pollution. But what if these solutions are not as protective as suggested? It turns out there are widespread misconceptions about wildfire smoke and its hazards, as well as the effectiveness of air filtration in protecting human health against wildfire smoke because this has been an understudied and consequently overlooked area of research. A scientific paper by Metalmark researchers uncovers critical flaws in current filter technologies and their assessment when it comes to capturing dangerous wildfire smoke particles. "There are a number of misconceptions about the size and behavior of particles generated by wildfires," explains Sissi Liu, CEO and co-founder of Metalmark Innovations. "This leads to a false sense of security when recommending filters tested using methods that don't account for the unique properties of smoke." The recent fires in Los Angeles have blanketed the region in thick smoke. The South Coast Air Quality Management District has reported PM2.5 levels up to 5 times the federal standard, prompting warnings to stay indoors. Understanding Wildfire Smoke and PM2.5 Wildfire smoke consists of fine particulate matter (PM) known as PM2.5, which includes particles smaller than 2.5 microns in diameter — approximately 1/30 the diameter of a human hair and smaller. While PM2.5 is a regulatory benchmark, this characterization fails to convey the size distribution of smoke particles. Practically all wildfire smoke particles are much smaller, averaging about 0.1-0.3 microns — roughly 1/350 the diameter of a human hair and smaller. This distinction is critical because smaller particles carrying toxic chemicals are more harmful, penetrating deep into the lungs and more capable of entering the bloodstream. Key Misconceptions About Wildfire Smoke Misconception #1. Smoke Particles Are Larger Than 1 Micron Wildfire smoke particles are predominantly submicron in size, forming as ultrafine particles (UFPs) immediately during combustion. Over tens of minutes, these particles stabilize between 0.1-0.3 microns, allowing them to travel vast distances without significant size changes. This stability means that harmful smoke particles from fires in Los Angeles can affect air quality across the US West Coast and the rest of the US. Misconception #2. Wildfire Smoke Is Just Like Any Other PM2.5 Unlike urban PM2.5, which often originates from traffic and industrial emissions, wildfire smoke is composed mainly of organic carbon compounds. Fires in the wildland-urban interface (WUI) include the combustion of biomass, building materials, vehicles, electronics, batteries, and more. They introduce additional toxins, including hydrogen cyanide, hydrogen fluoride, hydrogen chloride, isocyanates, dioxins, furans, chlorine, various toxic organic compounds (e.g., benzene, toluene, xylenes, styrene, formaldehyde), heavy metals (e.g., lead, chromium, cadmium, arsenic), and polycyclic aromatic hydrocarbons (PAHs). While some toxins, such as highly volatile formaldehyde, are transported in gaseous form, many of these toxic substances hitch a ride on smoke particles, often reported at diameters 200-300 nm or below, making them hazardous over long distances. Moreover, wildfire smoke aerosols are dynamic, containing semi-volatile organic compounds that can evaporate and react to form secondary pollutants, further degrading air quality and posing ongoing health threats. Smoke is even known to spread pathogens, contributing to rising cases of Valley Fever, for example. Misconception #3. Smoke Is Harmless If You’re Far from the Fire Smoke’s impact from large-scale extends far beyond the immediate vicinity of the fire. During the 2023 Canadian wildfires, for example, smoke traveled thousands of miles and caused hazardous air quality as far away as New York City and Atlanta. Despite the distance, the particle size and toxicity remain largely unchanged, leading to increased respiratory and cardiovascular health issues in affected regions. Research shows that faraway smoke increases cardiopulmonary disease and is associated with up to 1000-fold the premature deaths of the fires themselves. Misconception #4. Staying Indoors Provides Adequate Protection Many believe that staying indoors is a sufficient safeguard against wildfire smoke. However, smoke particles infiltrate buildings through gaps, ventilation systems, and even closed windows. Additionally, indoor air quality can degrade due to formaldehyde, ozone, and other chemicals — common byproducts of wildfires that penetrate indoors. Misconception #5. Current MERV-13 and HEPA Filters Provide Sufficient Protection While MERV-13 and HEPA filters are touted as effective solutions, they have limitations: Suboptimal Performance for Submicron Particles: Most HVAC filters, including MERV 13 and higher grades, are the least effective at capturing particles in the 0.1-0.3 micron range — precisely the size of wildfire smoke particles. Furthermore, their efficacy is not generally assessed for particles in the

[ramestoryworld]

As Los Angeles battles recent wildfires, air quality across the region has plummeted to hazardous levels. Based on authoritative recommendations, many have turned to air filters and purifiers as a defense against smoke pollution. But what if these solutions are not as protective as suggested? It turns out there are widespread misconceptions about wildfire smoke and its hazards, as well as the effectiveness of air filtration in protecting human health against wildfire smoke because this has been an understudied and consequently overlooked area of research. A scientific paper by Metalmark researchers uncovers critical flaws in current filter technologies and their assessment when it comes to capturing dangerous wildfire smoke particles. "There are a number of misconceptions about the size and behavior of particles generated by wildfires," explains Sissi Liu, CEO and co-founder of Metalmark Innovations. "This leads to a false sense of security when recommending filters tested using methods that don't account for the unique properties of smoke." The recent fires in Los Angeles have blanketed the region in thick smoke. The South Coast Air Quality Management District has reported PM2.5 levels up to 5 times the federal standard, prompting warnings to stay indoors. Understanding Wildfire Smoke and PM2.5 Wildfire smoke consists of fine particulate matter (PM) known as PM2.5, which includes particles smaller than 2.5 microns in diameter — approximately 1/30 the diameter of a human hair and smaller. While PM2.5 is a regulatory benchmark, this characterization fails to convey the size distribution of smoke particles. Practically all wildfire smoke particles are much smaller, averaging about 0.1-0.3 microns — roughly 1/350 the diameter of a human hair and smaller. This distinction is critical because smaller particles carrying toxic chemicals are more harmful, penetrating deep into the lungs and more capable of entering the bloodstream. Key Misconceptions About Wildfire Smoke Misconception #1. Smoke Particles Are Larger Than 1 Micron Wildfire smoke particles are predominantly submicron in size, forming as ultrafine particles (UFPs) immediately during combustion. Over tens of minutes, these particles stabilize between 0.1-0.3 microns, allowing them to travel vast distances without significant size changes. This stability means that harmful smoke particles from fires in Los Angeles can affect air quality across the US West Coast and the rest of the US. Misconception #2. Wildfire Smoke Is Just Like Any Other PM2.5 Unlike urban PM2.5, which often originates from traffic and industrial emissions, wildfire smoke is composed mainly of organic carbon compounds. Fires in the wildland-urban interface (WUI) include the combustion of biomass, building materials, vehicles, electronics, batteries, and more. They introduce additional toxins, including hydrogen cyanide, hydrogen fluoride, hydrogen chloride, isocyanates, dioxins, furans, chlorine, various toxic organic compounds (e.g., benzene, toluene, xylenes, styrene, formaldehyde), heavy metals (e.g., lead, chromium, cadmium, arsenic), and polycyclic aromatic hydrocarbons (PAHs). While some toxins, such as highly volatile formaldehyde, are transported in gaseous form, many of these toxic substances hitch a ride on smoke particles, often reported at diameters 200-300 nm or below, making them hazardous over long distances. Moreover, wildfire smoke aerosols are dynamic, containing semi-volatile organic compounds that can evaporate and react to form secondary pollutants, further degrading air quality and posing ongoing health threats. Smoke is even known to spread pathogens, contributing to rising cases of Valley Fever, for example. Misconception #3. Smoke Is Harmless If You’re Far from the Fire Smoke’s impact from large-scale extends far beyond the immediate vicinity of the fire. During the 2023 Canadian wildfires, for example, smoke traveled thousands of miles and caused hazardous air quality as far away as New York City and Atlanta. Despite the distance, the particle size and toxicity remain largely unchanged, leading to increased respiratory and cardiovascular health issues in affected regions. Research shows that faraway smoke increases cardiopulmonary disease and is associated with up to 1000-fold the premature deaths of the fires themselves. Misconception #4. Staying Indoors Provides Adequate Protection Many believe that staying indoors is a sufficient safeguard against wildfire smoke. However, smoke particles infiltrate buildings through gaps, ventilation systems, and even closed windows. Additionally, indoor air quality can degrade due to formaldehyde, ozone, and other chemicals — common byproducts of wildfires that penetrate indoors. Misconception #5. Current MERV-13 and HEPA Filters Provide Sufficient Protection While MERV-13 and HEPA filters are touted as effective solutions, they have limitations: Suboptimal Performance for Submicron Particles: Most HVAC filters, including MERV 13 and higher grades, are the least effective at capturing particles in the 0.1-0.3 micron range — precisely the size of wildfire smoke particles. Furthermore, their efficacy is not generally assessed for particles in the

[alexha2210]

As Los Angeles battles recent wildfires, air quality across the region has plummeted to hazardous levels. Based on authoritative recommendations, many have turned to air filters and purifiers as a defense against smoke pollution. But what if these solutions are not as protective as suggested? It turns out there are widespread misconceptions about wildfire smoke and its hazards, as well as the effectiveness of air filtration in protecting human health against wildfire smoke because this has been an understudied and consequently overlooked area of research. A scientific paper by Metalmark researchers uncovers critical flaws in current filter technologies and their assessment when it comes to capturing dangerous wildfire smoke particles. "There are a number of misconceptions about the size and behavior of particles generated by wildfires," explains Sissi Liu, CEO and co-founder of Metalmark Innovations. "This leads to a false sense of security when recommending filters tested using methods that don't account for the unique properties of smoke." The recent fires in Los Angeles have blanketed the region in thick smoke. The South Coast Air Quality Management District has reported PM2.5 levels up to 5 times the federal standard, prompting warnings to stay indoors. Understanding Wildfire Smoke and PM2.5 Wildfire smoke consists of fine particulate matter (PM) known as PM2.5, which includes particles smaller than 2.5 microns in diameter — approximately 1/30 the diameter of a human hair and smaller. While PM2.5 is a regulatory benchmark, this characterization fails to convey the size distribution of smoke particles. Practically all wildfire smoke particles are much smaller, averaging about 0.1-0.3 microns — roughly 1/350 the diameter of a human hair and smaller. This distinction is critical because smaller particles carrying toxic chemicals are more harmful, penetrating deep into the lungs and more capable of entering the bloodstream. Key Misconceptions About Wildfire Smoke Misconception #1. Smoke Particles Are Larger Than 1 Micron Wildfire smoke particles are predominantly submicron in size, forming as ultrafine particles (UFPs) immediately during combustion. Over tens of minutes, these particles stabilize between 0.1-0.3 microns, allowing them to travel vast distances without significant size changes. This stability means that harmful smoke particles from fires in Los Angeles can affect air quality across the US West Coast and the rest of the US. Misconception #2. Wildfire Smoke Is Just Like Any Other PM2.5 Unlike urban PM2.5, which often originates from traffic and industrial emissions, wildfire smoke is composed mainly of organic carbon compounds. Fires in the wildland-urban interface (WUI) include the combustion of biomass, building materials, vehicles, electronics, batteries, and more. They introduce additional toxins, including hydrogen cyanide, hydrogen fluoride, hydrogen chloride, isocyanates, dioxins, furans, chlorine, various toxic organic compounds (e.g., benzene, toluene, xylenes, styrene, formaldehyde), heavy metals (e.g., lead, chromium, cadmium, arsenic), and polycyclic aromatic hydrocarbons (PAHs). While some toxins, such as highly volatile formaldehyde, are transported in gaseous form, many of these toxic substances hitch a ride on smoke particles, often reported at diameters 200-300 nm or below, making them hazardous over long distances. Moreover, wildfire smoke aerosols are dynamic, containing semi-volatile organic compounds that can evaporate and react to form secondary pollutants, further degrading air quality and posing ongoing health threats. Smoke is even known to spread pathogens, contributing to rising cases of Valley Fever, for example. Misconception #3. Smoke Is Harmless If You’re Far from the Fire Smoke’s impact from large-scale extends far beyond the immediate vicinity of the fire. During the 2023 Canadian wildfires, for example, smoke traveled thousands of miles and caused hazardous air quality as far away as New York City and Atlanta. Despite the distance, the particle size and toxicity remain largely unchanged, leading to increased respiratory and cardiovascular health issues in affected regions. Research shows that faraway smoke increases cardiopulmonary disease and is associated with up to 1000-fold the premature deaths of the fires themselves. Misconception #4. Staying Indoors Provides Adequate Protection Many believe that staying indoors is a sufficient safeguard against wildfire smoke. However, smoke particles infiltrate buildings through gaps, ventilation systems, and even closed windows. Additionally, indoor air quality can degrade due to formaldehyde, ozone, and other chemicals — common byproducts of wildfires that penetrate indoors. Misconception #5. Current MERV-13 and HEPA Filters Provide Sufficient Protection While MERV-13 and HEPA filters are touted as effective solutions, they have limitations: Suboptimal Performance for Submicron Particles: Most HVAC filters, including MERV 13 and higher grades, are the least effective at capturing particles in the 0.1-0.3 micron range — precisely the size of wildfire smoke particles. Furthermore, their efficacy is not generally assessed for particles in the

[angusstory]

As Los Angeles battles recent wildfires, air quality across the region has plummeted to hazardous levels. Based on authoritative recommendations, many have turned to air filters and purifiers as a defense against smoke pollution. But what if these solutions are not as protective as suggested? It turns out there are widespread misconceptions about wildfire smoke and its hazards, as well as the effectiveness of air filtration in protecting human health against wildfire smoke because this has been an understudied and consequently overlooked area of research. A scientific paper by Metalmark researchers uncovers critical flaws in current filter technologies and their assessment when it comes to capturing dangerous wildfire smoke particles. "There are a number of misconceptions about the size and behavior of particles generated by wildfires," explains Sissi Liu, CEO and co-founder of Metalmark Innovations. "This leads to a false sense of security when recommending filters tested using methods that don't account for the unique properties of smoke." The recent fires in Los Angeles have blanketed the region in thick smoke. The South Coast Air Quality Management District has reported PM2.5 levels up to 5 times the federal standard, prompting warnings to stay indoors. Understanding Wildfire Smoke and PM2.5 Wildfire smoke consists of fine particulate matter (PM) known as PM2.5, which includes particles smaller than 2.5 microns in diameter — approximately 1/30 the diameter of a human hair and smaller. While PM2.5 is a regulatory benchmark, this characterization fails to convey the size distribution of smoke particles. Practically all wildfire smoke particles are much smaller, averaging about 0.1-0.3 microns — roughly 1/350 the diameter of a human hair and smaller. This distinction is critical because smaller particles carrying toxic chemicals are more harmful, penetrating deep into the lungs and more capable of entering the bloodstream. Key Misconceptions About Wildfire Smoke Misconception #1. Smoke Particles Are Larger Than 1 Micron Wildfire smoke particles are predominantly submicron in size, forming as ultrafine particles (UFPs) immediately during combustion. Over tens of minutes, these particles stabilize between 0.1-0.3 microns, allowing them to travel vast distances without significant size changes. This stability means that harmful smoke particles from fires in Los Angeles can affect air quality across the US West Coast and the rest of the US. Misconception #2. Wildfire Smoke Is Just Like Any Other PM2.5 Unlike urban PM2.5, which often originates from traffic and industrial emissions, wildfire smoke is composed mainly of organic carbon compounds. Fires in the wildland-urban interface (WUI) include the combustion of biomass, building materials, vehicles, electronics, batteries, and more. They introduce additional toxins, including hydrogen cyanide, hydrogen fluoride, hydrogen chloride, isocyanates, dioxins, furans, chlorine, various toxic organic compounds (e.g., benzene, toluene, xylenes, styrene, formaldehyde), heavy metals (e.g., lead, chromium, cadmium, arsenic), and polycyclic aromatic hydrocarbons (PAHs). While some toxins, such as highly volatile formaldehyde, are transported in gaseous form, many of these toxic substances hitch a ride on smoke particles, often reported at diameters 200-300 nm or below, making them hazardous over long distances. Moreover, wildfire smoke aerosols are dynamic, containing semi-volatile organic compounds that can evaporate and react to form secondary pollutants, further degrading air quality and posing ongoing health threats. Smoke is even known to spread pathogens, contributing to rising cases of Valley Fever, for example. Misconception #3. Smoke Is Harmless If You’re Far from the Fire Smoke’s impact from large-scale extends far beyond the immediate vicinity of the fire. During the 2023 Canadian wildfires, for example, smoke traveled thousands of miles and caused hazardous air quality as far away as New York City and Atlanta. Despite the distance, the particle size and toxicity remain largely unchanged, leading to increased respiratory and cardiovascular health issues in affected regions. Research shows that faraway smoke increases cardiopulmonary disease and is associated with up to 1000-fold the premature deaths of the fires themselves. Misconception #4. Staying Indoors Provides Adequate Protection Many believe that staying indoors is a sufficient safeguard against wildfire smoke. However, smoke particles infiltrate buildings through gaps, ventilation systems, and even closed windows. Additionally, indoor air quality can degrade due to formaldehyde, ozone, and other chemicals — common byproducts of wildfires that penetrate indoors. Misconception #5. Current MERV-13 and HEPA Filters Provide Sufficient Protection While MERV-13 and HEPA filters are touted as effective solutions, they have limitations: Suboptimal Performance for Submicron Particles: Most HVAC filters, including MERV 13 and higher grades, are the least effective at capturing particles in the 0.1-0.3 micron range — precisely the size of wildfire smoke particles. Furthermore, their efficacy is not generally assessed for particles in the

[tumibaba]

As Los Angeles battles recent wildfires, air quality across the region has plummeted to hazardous levels. Based on authoritative recommendations, many have turned to air filters and purifiers as a defense against smoke pollution. But what if these solutions are not as protective as suggested? It turns out there are widespread misconceptions about wildfire smoke and its hazards, as well as the effectiveness of air filtration in protecting human health against wildfire smoke because this has been an understudied and consequently overlooked area of research. A scientific paper by Metalmark researchers uncovers critical flaws in current filter technologies and their assessment when it comes to capturing dangerous wildfire smoke particles. "There are a number of misconceptions about the size and behavior of particles generated by wildfires," explains Sissi Liu, CEO and co-founder of Metalmark Innovations. "This leads to a false sense of security when recommending filters tested using methods that don't account for the unique properties of smoke." The recent fires in Los Angeles have blanketed the region in thick smoke. The South Coast Air Quality Management District has reported PM2.5 levels up to 5 times the federal standard, prompting warnings to stay indoors. Understanding Wildfire Smoke and PM2.5 Wildfire smoke consists of fine particulate matter (PM) known as PM2.5, which includes particles smaller than 2.5 microns in diameter — approximately 1/30 the diameter of a human hair and smaller. While PM2.5 is a regulatory benchmark, this characterization fails to convey the size distribution of smoke particles. Practically all wildfire smoke particles are much smaller, averaging about 0.1-0.3 microns — roughly 1/350 the diameter of a human hair and smaller. This distinction is critical because smaller particles carrying toxic chemicals are more harmful, penetrating deep into the lungs and more capable of entering the bloodstream. Key Misconceptions About Wildfire Smoke Misconception #1. Smoke Particles Are Larger Than 1 Micron Wildfire smoke particles are predominantly submicron in size, forming as ultrafine particles (UFPs) immediately during combustion. Over tens of minutes, these particles stabilize between 0.1-0.3 microns, allowing them to travel vast distances without significant size changes. This stability means that harmful smoke particles from fires in Los Angeles can affect air quality across the US West Coast and the rest of the US. Misconception #2. Wildfire Smoke Is Just Like Any Other PM2.5 Unlike urban PM2.5, which often originates from traffic and industrial emissions, wildfire smoke is composed mainly of organic carbon compounds. Fires in the wildland-urban interface (WUI) include the combustion of biomass, building materials, vehicles, electronics, batteries, and more. They introduce additional toxins, including hydrogen cyanide, hydrogen fluoride, hydrogen chloride, isocyanates, dioxins, furans, chlorine, various toxic organic compounds (e.g., benzene, toluene, xylenes, styrene, formaldehyde), heavy metals (e.g., lead, chromium, cadmium, arsenic), and polycyclic aromatic hydrocarbons (PAHs). While some toxins, such as highly volatile formaldehyde, are transported in gaseous form, many of these toxic substances hitch a ride on smoke particles, often reported at diameters 200-300 nm or below, making them hazardous over long distances. Moreover, wildfire smoke aerosols are dynamic, containing semi-volatile organic compounds that can evaporate and react to form secondary pollutants, further degrading air quality and posing ongoing health threats. Smoke is even known to spread pathogens, contributing to rising cases of Valley Fever, for example. Misconception #3. Smoke Is Harmless If You’re Far from the Fire Smoke’s impact from large-scale extends far beyond the immediate vicinity of the fire. During the 2023 Canadian wildfires, for example, smoke traveled thousands of miles and caused hazardous air quality as far away as New York City and Atlanta. Despite the distance, the particle size and toxicity remain largely unchanged, leading to increased respiratory and cardiovascular health issues in affected regions. Research shows that faraway smoke increases cardiopulmonary disease and is associated with up to 1000-fold the premature deaths of the fires themselves. Misconception #4. Staying Indoors Provides Adequate Protection Many believe that staying indoors is a sufficient safeguard against wildfire smoke. However, smoke particles infiltrate buildings through gaps, ventilation systems, and even closed windows. Additionally, indoor air quality can degrade due to formaldehyde, ozone, and other chemicals — common byproducts of wildfires that penetrate indoors. Misconception #5. Current MERV-13 and HEPA Filters Provide Sufficient Protection While MERV-13 and HEPA filters are touted as effective solutions, they have limitations: Suboptimal Performance for Submicron Particles: Most HVAC filters, including MERV 13 and higher grades, are the least effective at capturing particles in the 0.1-0.3 micron range — precisely the size of wildfire smoke particles. Furthermore, their efficacy is not generally assessed for particles in the

[romaleen]

As Los Angeles battles recent wildfires, air quality across the region has plummeted to hazardous levels. Based on authoritative recommendations, many have turned to air filters and purifiers as a defense against smoke pollution. But what if these solutions are not as protective as suggested? It turns out there are widespread misconceptions about wildfire smoke and its hazards, as well as the effectiveness of air filtration in protecting human health against wildfire smoke because this has been an understudied and consequently overlooked area of research. A scientific paper by Metalmark researchers uncovers critical flaws in current filter technologies and their assessment when it comes to capturing dangerous wildfire smoke particles. "There are a number of misconceptions about the size and behavior of particles generated by wildfires," explains Sissi Liu, CEO and co-founder of Metalmark Innovations. "This leads to a false sense of security when recommending filters tested using methods that don't account for the unique properties of smoke." The recent fires in Los Angeles have blanketed the region in thick smoke. The South Coast Air Quality Management District has reported PM2.5 levels up to 5 times the federal standard, prompting warnings to stay indoors. Understanding Wildfire Smoke and PM2.5 Wildfire smoke consists of fine particulate matter (PM) known as PM2.5, which includes particles smaller than 2.5 microns in diameter — approximately 1/30 the diameter of a human hair and smaller. While PM2.5 is a regulatory benchmark, this characterization fails to convey the size distribution of smoke particles. Practically all wildfire smoke particles are much smaller, averaging about 0.1-0.3 microns — roughly 1/350 the diameter of a human hair and smaller. This distinction is critical because smaller particles carrying toxic chemicals are more harmful, penetrating deep into the lungs and more capable of entering the bloodstream. Key Misconceptions About Wildfire Smoke Misconception #1. Smoke Particles Are Larger Than 1 Micron Wildfire smoke particles are predominantly submicron in size, forming as ultrafine particles (UFPs) immediately during combustion. Over tens of minutes, these particles stabilize between 0.1-0.3 microns, allowing them to travel vast distances without significant size changes. This stability means that harmful smoke particles from fires in Los Angeles can affect air quality across the US West Coast and the rest of the US. Misconception #2. Wildfire Smoke Is Just Like Any Other PM2.5 Unlike urban PM2.5, which often originates from traffic and industrial emissions, wildfire smoke is composed mainly of organic carbon compounds. Fires in the wildland-urban interface (WUI) include the combustion of biomass, building materials, vehicles, electronics, batteries, and more. They introduce additional toxins, including hydrogen cyanide, hydrogen fluoride, hydrogen chloride, isocyanates, dioxins, furans, chlorine, various toxic organic compounds (e.g., benzene, toluene, xylenes, styrene, formaldehyde), heavy metals (e.g., lead, chromium, cadmium, arsenic), and polycyclic aromatic hydrocarbons (PAHs). While some toxins, such as highly volatile formaldehyde, are transported in gaseous form, many of these toxic substances hitch a ride on smoke particles, often reported at diameters 200-300 nm or below, making them hazardous over long distances. Moreover, wildfire smoke aerosols are dynamic, containing semi-volatile organic compounds that can evaporate and react to form secondary pollutants, further degrading air quality and posing ongoing health threats. Smoke is even known to spread pathogens, contributing to rising cases of Valley Fever, for example. Misconception #3. Smoke Is Harmless If You’re Far from the Fire Smoke’s impact from large-scale extends far beyond the immediate vicinity of the fire. During the 2023 Canadian wildfires, for example, smoke traveled thousands of miles and caused hazardous air quality as far away as New York City and Atlanta. Despite the distance, the particle size and toxicity remain largely unchanged, leading to increased respiratory and cardiovascular health issues in affected regions. Research shows that faraway smoke increases cardiopulmonary disease and is associated with up to 1000-fold the premature deaths of the fires themselves. Misconception #4. Staying Indoors Provides Adequate Protection Many believe that staying indoors is a sufficient safeguard against wildfire smoke. However, smoke particles infiltrate buildings through gaps, ventilation systems, and even closed windows. Additionally, indoor air quality can degrade due to formaldehyde, ozone, and other chemicals — common byproducts of wildfires that penetrate indoors. Misconception #5. Current MERV-13 and HEPA Filters Provide Sufficient Protection While MERV-13 and HEPA filters are touted as effective solutions, they have limitations: Suboptimal Performance for Submicron Particles: Most HVAC filters, including MERV 13 and higher grades, are the least effective at capturing particles in the 0.1-0.3 micron range — precisely the size of wildfire smoke particles. Furthermore, their efficacy is not generally assessed for particles in the

[monaleen101]

As Los Angeles battles recent wildfires, air quality across the region has plummeted to hazardous levels. Based on authoritative recommendations, many have turned to air filters and purifiers as a defense against smoke pollution. But what if these solutions are not as protective as suggested? It turns out there are widespread misconceptions about wildfire smoke and its hazards, as well as the effectiveness of air filtration in protecting human health against wildfire smoke because this has been an understudied and consequently overlooked area of research. A scientific paper by Metalmark researchers uncovers critical flaws in current filter technologies and their assessment when it comes to capturing dangerous wildfire smoke particles. "There are a number of misconceptions about the size and behavior of particles generated by wildfires," explains Sissi Liu, CEO and co-founder of Metalmark Innovations. "This leads to a false sense of security when recommending filters tested using methods that don't account for the unique properties of smoke." The recent fires in Los Angeles have blanketed the region in thick smoke. The South Coast Air Quality Management District has reported PM2.5 levels up to 5 times the federal standard, prompting warnings to stay indoors. Understanding Wildfire Smoke and PM2.5 Wildfire smoke consists of fine particulate matter (PM) known as PM2.5, which includes particles smaller than 2.5 microns in diameter — approximately 1/30 the diameter of a human hair and smaller. While PM2.5 is a regulatory benchmark, this characterization fails to convey the size distribution of smoke particles. Practically all wildfire smoke particles are much smaller, averaging about 0.1-0.3 microns — roughly 1/350 the diameter of a human hair and smaller. This distinction is critical because smaller particles carrying toxic chemicals are more harmful, penetrating deep into the lungs and more capable of entering the bloodstream. Key Misconceptions About Wildfire Smoke Misconception #1. Smoke Particles Are Larger Than 1 Micron Wildfire smoke particles are predominantly submicron in size, forming as ultrafine particles (UFPs) immediately during combustion. Over tens of minutes, these particles stabilize between 0.1-0.3 microns, allowing them to travel vast distances without significant size changes. This stability means that harmful smoke particles from fires in Los Angeles can affect air quality across the US West Coast and the rest of the US. Misconception #2. Wildfire Smoke Is Just Like Any Other PM2.5 Unlike urban PM2.5, which often originates from traffic and industrial emissions, wildfire smoke is composed mainly of organic carbon compounds. Fires in the wildland-urban interface (WUI) include the combustion of biomass, building materials, vehicles, electronics, batteries, and more. They introduce additional toxins, including hydrogen cyanide, hydrogen fluoride, hydrogen chloride, isocyanates, dioxins, furans, chlorine, various toxic organic compounds (e.g., benzene, toluene, xylenes, styrene, formaldehyde), heavy metals (e.g., lead, chromium, cadmium, arsenic), and polycyclic aromatic hydrocarbons (PAHs). While some toxins, such as highly volatile formaldehyde, are transported in gaseous form, many of these toxic substances hitch a ride on smoke particles, often reported at diameters 200-300 nm or below, making them hazardous over long distances. Moreover, wildfire smoke aerosols are dynamic, containing semi-volatile organic compounds that can evaporate and react to form secondary pollutants, further degrading air quality and posing ongoing health threats. Smoke is even known to spread pathogens, contributing to rising cases of Valley Fever, for example. Misconception #3. Smoke Is Harmless If You’re Far from the Fire Smoke’s impact from large-scale extends far beyond the immediate vicinity of the fire. During the 2023 Canadian wildfires, for example, smoke traveled thousands of miles and caused hazardous air quality as far away as New York City and Atlanta. Despite the distance, the particle size and toxicity remain largely unchanged, leading to increased respiratory and cardiovascular health issues in affected regions. Research shows that faraway smoke increases cardiopulmonary disease and is associated with up to 1000-fold the premature deaths of the fires themselves. Misconception #4. Staying Indoors Provides Adequate Protection Many believe that staying indoors is a sufficient safeguard against wildfire smoke. However, smoke particles infiltrate buildings through gaps, ventilation systems, and even closed windows. Additionally, indoor air quality can degrade due to formaldehyde, ozone, and other chemicals — common byproducts of wildfires that penetrate indoors. Misconception #5. Current MERV-13 and HEPA Filters Provide Sufficient Protection While MERV-13 and HEPA filters are touted as effective solutions, they have limitations: Suboptimal Performance for Submicron Particles: Most HVAC filters, including MERV 13 and higher grades, are the least effective at capturing particles in the 0.1-0.3 micron range — precisely the size of wildfire smoke particles. Furthermore, their efficacy is not generally assessed for particles in the