[Due to the increasing size of the archives, each topic page now contains only the prior 365 days of content. Access to older stories is now solely through the Monthly Archive pages or the site search function.]
Study links California regulations, significant declines in cancer risk from exposure to air toxics
September 22, 2015
A study by a team from the California Air Resources Board (ARB) has found that the collective cancer risk from exposure to seven toxic air contaminant (TACs) has declined 76% during the period from 1990 to 2012, and linked that result from air quality regulations targeting these TACs. The study appears in the ACS journal Environmental Science & Technology.
Of the seven TACs, diesel particulate matter (DPM) is the most important; DPM is emitted mainly from trucks and buses and is responsible for most of the airborne cancer risk in California, according to ARB. However, in the study DPM is not measured directly. Based on a novel surrogate method, DPM concentrations declined 68% during the period, even though the state’s population increased 31%; diesel vehicle-miles-traveled increased 81%; and the gross state product (GSP) increased 74%.
NRC Canada team investigates effect of gasoline particulate filter on PM from light-duty GDI engine
September 17, 2015
A team led by researchers from the National Research Council Canada has investigated the effect of the use of a gasoline particulate filter on the size and morphology of PM emitted from a light-duty gasoline-direct-injection (GDI) vehicle over the FTP-75 and US06 transient drive cycles.
Using transmission-electron-microscope (TEM) image analysis, they compared PM from a 2012 Ford Focus powered by a 2.0-liter wall-guided GDI engine, operating under globally stoichiometric condition, to the results for the same vehicle equipped with a catalyzed gasoline particulate filter (GPF). A paper describing their results is published in the ACS journal Environmental Science & Technology.
Air pollution could claim 6.6 million lives per year by 2050, double current rate; small domestic fires and ag the worst offenders
If air pollution emissions continue to rise at the current rate, some 6.6 million people could prematurely die annually by 2050, double the current rate of 3.3 million people per year, according to a study carried out by a team led by researchers at the Max Planck Institute for Chemistry in Mainz. The largest sources of air pollution are not industry and transport but small domestic fires and agriculture. Results of the study are published in the journal Nature.
Exposure to air pollution is particularly acute in Asia, especially in China and India, where three-quarters of the world’s pollution-related deaths occur. The team headed by Johannes Lelieveld, Director at the Max Planck Institute for Chemistry, reported that 1.4 million people per year in China and 650,000 people in India die every year as a consequence of air pollution. In the EU exposure to fine particles and ozone claims 180,000 lives a year, including 35,000 in Germany. In many countries, air pollution accounts for roughly ten-times more deaths than road accidents.
Crowdsourcing air pollution measurements: iSPEX-EU 2015
September 06, 2015
A collaboration led by researchers at Leiden University in The Netherlands has launched a Europe-wide citizen campaign—iSPEX-EU 2015—to use a smartphone add-on and app to measure atmospheric aerosols (tiny particles), resulting in a broad-based data set with high spatio-temporal resolution.
Atmospheric aerosols play an important but as-yet poorly understood role in climate and air quality, with significant impacts on the environment, health, and air traffic. Satellite-based aerosol monitoring is, despite its global coverage, limited in spatial and temporal resolution (with global coverage up to once a day with a ground resolution of a few kilometers only), and lacks sufficient information on aerosol particle characteristics. Therefore, the researchers say, a different strategy is needed to overcome these current limitations.
Air pollution associated with increased heart attack risk despite “safe” levels
August 31, 2015
Particulate matter and NO2 air pollution are associated with increased risk of severe heart attacks despite being within European recommended levels, according to research presented at ESC Congress by Dr. Jean-Francois Argacha, a cardiologist at University Hospital Brussels (UZ Brussel-Vrije Universiteit Brussel), in Belgium.
The study investigated the effect of short term exposure to air pollution on the risk of ST-segment elevation myocardial infarction (STEMI)—a deadly type of heart attack that is caused by a prolonged blockage of blood supply in the heart. This type of myocardial infarction has the worst prognosis and is caused by thrombotic occlusion of a coronary artery that damages the heart.
Health Effects Institute to release Executive Summary of ACES new-technology diesel results this fall
August 21, 2015
The Health Effects Institute (HEI) it will publish an Executive Summary of the Advanced Collaborative Emissions Study (ACES) this fall. The Summary will be the synopsis and final publication from the program to characterize the emissions and assess the health effects of new-technology diesel exhaust (NTDE) from heavy-duty diesel engines that meet the 2007 and 2010 regulations enacted by the US Environmental Protection Agency (EPA). (Earlier post.) HEI is an independent, non-profit research institute funded jointly by the US Environmental Protection Agency (EPA) and the worldwide motor vehicle industry.
To meet new emissions limits, diesel-engine manufacturers developed new exhaust aftertreatment systems and the petroleum industry introduced new ultra-low-sulfur diesel fuel needed to allow the new emissions controls to work. HEI—in collaboration with the Coordinating Research Council, a nonprofit organization with extensive expertise in emissions characterization—launched ACES in response to requests to characterize the emissions and health effects of NTDE.
UC Riverside team characterizes impact on PM of fuels with varying aromatics and octane rating; benefit of increased ethanol fraction
August 18, 2015
Researchers at the University of California-Riverside have characterized the effect of decreased aromatic content fuels combusted in advanced vehicle technologies on emissions of particulate matter (PM). In a paper in the ACS journal Environmental Science & Technology, they present the changes in PM emissions for different fuels, engine technologies, and operating conditions. Among their findings is that an increased ethanol fraction in gasoline could help reduce PM mass and black carbon (BC) from gasoline direct injection engines (GDI).
Typical commercial gasoline comprises varying concentrations of aromatic hydrocarbons and octane ratings; the impacts on PM such as black carbon (BC) and water-soluble and insoluble particle compositions of these differences are not well-defined. The UC Riverside study tested seven 2012 model year vehicles, including one port fuel injection (PFI) configured hybrid vehicle; one PFI vehicle; and six GDI vehicles.
Berkeley Earth study calculates that air pollution contributes to 1.6M deaths per year in China
August 14, 2015
In an analysis of hourly air pollution data (PM2.5,PM10, SO2, NO2, O3 and CO) from more than 1500 sites in China, Berkeley Earth has calculated that the observed air pollution contributes to ~1.6 million deaths/year in China [0.7–2.2 million deaths/year at 95% confidence]—roughly 17% of all deaths in China. The calculated mortality is somewhat higher than the 1.2 million deaths/year previously estimated from a Huai River study using Chinese air pollution measurements and mortality data. A paper on the analysis has been accepted for publication in the journal PLoS ONE.
In the study, the independent non-profit applied Kriging interpolation (a geostatistical interpolation technique) to four months of data to derive pollution maps for eastern China. Consistent with prior findings, the greatest pollution occurs in the east; however, significant levels are widespread across northern and central China and are not limited to major cities or geologic basins. Sources of pollution are widespread, but are particularly intense in a northeast corridor that extends from near Shanghai to north of Beijing.
Study finds single exposure to roadway PM induces transient pulmonary stress; possible need to regulate non-tailpipe-related pollution
July 13, 2015
A study by researchers in Israel and the US has found that single (“sub-clinical”) exposure to extracts from particulate material (PM) collected in a near roadway environment can induce a transient oxidative stress and inflammation in mice’ lungs. The researchers attributed this largely to the dissolved metals (such as Cu, Fe, Mn, V, Ni, and Cr) that are part of roadway emissions.
The local response was largely self-resolved by 48 h, suggesting that it could represent a subclinical response to everyday-level exposure. Removal of soluble metals by chelation markedly diminished the pulmonary response. The paper appears in the ACS journal Environmental Science & Technology.
Northwestern-led team develops hydrogenation catalyst selective for carcinogen benzene; cleaner gasoline
June 09, 2015
A team from Northwestern University, with colleagues from UOP LLC, a Honeywell Company; Universita’ degli Studi di Roma “La Sapienza”; Argonne National Laboratory; and Ames Laboratory has developed a new hydrogenation catalyst that is highly selective for benzene, an aromatic—and known carcinogen—that is part of conventional gasoline.
The new catalyst could cost-effectively remove benzene from the other aromatic compounds in gasoline, making it cleaner but without eliminating other aromatics; aromatics in gasoline are used to improve gas octane numbers and fuel efficiency. An open access paper on their work is published in the Journal of the American Chemical Society.
EPA draft assessment finds no widespread, systemic impacts to drinking water resources from fracking
June 05, 2015
The US Environmental Protection Agency (EPA) released a draft assessment on the potential impacts of hydraulic fracturing activities on drinking water resources in the United States. The assessment, done at the request of Congress, found that hydraulic fracturing activities in the US are carried out in a way that have not led to widespread, systemic impacts on drinking water resources.
The assessment followed the water used for hydraulic fracturing from water acquisition; chemical mixing at the well pad site; well injection of fracking fluids; the collection of hydraulic fracturing wastewater (including flowback and produced water); and wastewater treatment and disposal. The assessment also identified potential vulnerabilities in the water lifecycle—some of which are not unique to hydraulic fracturing—that could impact drinking water.
Early exposure to PM2.5 associated with increased risk of childhood autism; causality unproven
May 21, 2015
Exposure to fine particulate air pollution (PM2.5) during pregnancy through the first two years of a child’s life may be associated with an increased risk of the child developing autism spectrum disorder (ASD), a condition that affects one in 68 children, according to a University of Pittsburgh Graduate School of Public Health investigation of children in southwestern Pennsylvania.
The research is funded by The Heinz Endowments and published in the July edition of Environmental Research.
Study concludes air pollution directly affects cognition
May 19, 2015
Results of new analysis conducted by German and Swiss researchers suggests that air pollution directly affects cognition and is not mediated by lung function; put another way, the two are independent risk factors for cognitive decline. Although earlier studies showed that both air pollution and impaired lung function can cause cognitive deficits, it was up to now unclear whether air pollution diminishes cognition by reducing breathing ability first or whether air pollution represents an independent risk factor for cognitive deficit.
The researchers, who analyzed data from a study of 834 elderly German women, presented their findings at ATS 2015 in Denver.
U Toronto studies find traffic emissions spread farther than thought; 25% of cars causing 90% of pollution
April 28, 2015
A trio of recently published studies from a team of University of Toronto engineers has found that air pollution could be spreading up to three times farther than thought, contributing to varying levels of air quality across cities.
Past research on tailpipe criteria pollutants has shown poor air quality anywhere between 100 to 250 meters of major roadways. But in an open access paper published in the recent edition of the journal Atmospheric Pollution Research, U of T chemical engineer Greg Evans and his partners at Environment Canada have found that concentrations of pollutants from traffic are still double at a distance of 280 meters downwind from highway 400 north of Toronto.
CMU study finds controlled EV charging can reduce generation cost, but at greater health and environmental costs depending upon the generation mix
April 16, 2015
In a study focused on the PJM portion of the US electricity grid, researchers at Carnegie Mellon University (CMU) found that although charging electric vehicles at night (when electricity is cheap and wind power is typically more plentiful) could lower electricity costs, doing so also creates more air emissions, and that the health and environmental costs from these emissions outweigh the electricity cost savings. A paper describing the work is published in the ACS journal Environmental Science & Technology.
Results from the study also suggest that with sufficient coal plant retirement and sufficient wind power, controlled charging could result in positive net benefits instead of negative. The result of the analysis depends on the details of the region, notes CMU Professor Jeremy Michalek, corresponding author—i.e., other parts of the US and the world could be different. The question of electricity costs vs. health and environmental cost is important to ask everywhere, Michalek said.
Georgia Tech study projects potential mixed impacts of climate change policies on air quality
April 08, 2015
Results of a study by a team from Georgia Tech and their colleagues at NASA Goddard Institute for Space Studies and Northeast States for Coordinated Air Use Management show that national CO2emissions reductions strategies will play an important role in impacting air quality over the US. The results also show that CO2 emission reduction policies can have mixed positive and negative impacts on air quality. A paper on the study is published in the ACS journal Environmental Science & Technology.
In the study, the researchers assessed the impact of four potential climate mitigation policies—two climate tax scenarios (CT1 and CT2); a combined transportation and energy scenario (TE); a biomass energy (BE) scenario; plus a reference case—on air quality in the US in 2050 using a chemical transport model (CTM) to simulate air pollutant concentrations and applying recent climate downscaling and emissions modeling advancements.
New study finds asthma morbidity in children is enhanced in areas with high traffic-related air pollution near the home
April 07, 2015
Results from a new study by researchers at the University of California Irvine support a growing body of scientific literature indicating that sensitive populations, including children, certain ethnic groups and people of lower socioeconomic status, are more vulnerable to the effects of high exposures to traffic-related air pollution.
The UC Irvine study, which examined the effect of chronic exposure in asthmatic children living in homes near traffic pollution, was led by Ralph J. Delfino, MD, PhD, at the Department of Epidemiology. Asthma is a chronic inflammatory disorder of the airways; chronic inflammation is associated with airway (bronchial) hyperresponsiveness that leads to recurrent episodes of wheezing, breathlessness, chest tightness, and coughing. The study was funded by the California Air Resources Board (ARB) and benefited from funding by the South Coast Air Quality Management District (SCAQMD).
U Toronto LCA suggests that with CNG as primary vehicle energy source, EVs best targeted at non-attainment areas
April 01, 2015
A team at the University of Toronto has examined the life cycle air emissions (climate change and human health) impact benefits and life cycle ownership costs of compressed natural gas (CNG) use directly in conventional vehicles (CV) and hybrid electric vehicles (HEV), and natural gas-derived electricity (NG-e) use in plug-in battery electric vehicles (BEV), using a gasoline-fueled conventional vehicle as a reference.
Among their findings, published in a paper in the ACS journal Environmental Science & Technology, are that policies should for the foreseeable future focus on the niche adoption of plug-in vehicles in non-attainment regions, as CNG vehicles are likely more cost-effective at providing overall life cycle air emissions impact benefits.
Evidence from glacier ice: Until it was banned, leaded gasoline dominated the anthropogenic lead emissions in South America
March 08, 2015
Leaded gasoline was a larger emission source of the toxic heavy metal lead than mining in South America, even though the extraction of metals from the region’s mines historically released huge quantities of lead into the environment, according to a study by researchers from the Paul Scherrer Institute PSI and the University of Bern.
The team discovered evidence of the dominance of leaded gasoline based on measurements in an ice core from Illimani glacier in Bolivia; Illimani is the highest mountain of the eastern Bolivian Andes and is located at the northeastern margin of the Andean Altiplano. The scientists found that lead from road traffic in the neighboring countries polluted the air twice as heavily as regional mining from the 1960s onwards. An open access paper on the work is published in the journal Science Advances.
HEI ACES study of lifetime animal exposure to New Technology Diesel Engine exhaust finds no lung cancer
January 27, 2015
The first study to conduct a comprehensive evaluation of lifetime exposure to new technology diesel exhaust (NTDE)—i.e., exhaust from heavy-duty diesel engines meeting EPA 2007 and later emissions requirements—has found no evidence of carcinogenic lung tumors. The Advanced Collaborative Emissions Study (ACES), released today by the Health Effects Institute (HEI), also confirmed that the concentrations of particulate matter and toxic air pollutants emitted from NTDE are more than 90% lower than emissions from traditional older diesel engines (TDE). (Earlier post.) HEI is an independent, non-profit research institute funded jointly by the US Environmental Protection Agency (EPA) and the worldwide motor vehicle industry.
The study exposed laboratory rats 80 hours a week, for up to 30 months, to emissions from a heavy-duty diesel engine meeting 2007 US EPA standards using new filters and other control technology. The study evaluated the long-term effects of multiple concentrations of inhaled NTDE in male and female rats on more than 100 different biologic endpoints, including tumor development, and compared the results with biologic effects seen in earlier studies in rats after exposure to TDE.
UBC study associates exposure to diesel exhaust with changes in DNA methylation
January 09, 2015
As an organism lives and grows, chemical reactions activate and deactivate parts of its genome at strategic times and in specific location. (Epigenetics is the study of these reactions.) DNA methylation—a chemical process in which a methyl group is added to cytosine primarily in the context of a cytosine-guanine dinucleotide (CpG)—is one of several epigenetic mechanisms that cells use to control gene expression.
While changes in DNA methylation have been associated with traffic-related air pollution in observational studies, the specific mechanisms have not been explored in a controlled study of asthmatics. In an open access study published in the journal Particle and Fibre Toxicology, a team from the University of British Columbia investigated the short-term effects of diesel exhaust inhalation on DNA methylation levels at CpG sites across the genome in circulating blood in asthmatics.
New Volvo XC90 debuts enhanced multi-filter that improves interior air quality
November 13, 2014
Volvo is introducing a larger, more efficient multi-filter in its cabins as part of its CleanZone initiative. CleanZone is an approach to controlling interior air quality and providing a better driving environment through innovative solutions for enhanced wellbeing and health. Drivers can breathe easier because most microscopic, hazardous “fine dust” particles will now be prevented from entering the car.
The multi-filter was designed especially for the SPA platform and will first appear in the all-new XC90 in the beginning of 2015. It features a larger design that intercepts more particulates and pollen, as well as a layer of active charcoal that effectively removes a range of contaminants that can impact the health of drivers.