Airborne interactions between viruses and PM2.5 as an unexplored modifier of viral viability

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Millions of people die each year from long-term exposure to fine particulate matter, classified as PM2.5. Studies have also shown a correlation between influenza-like illness and increased PM2.5. Although it’s well known that microorganisms exist in particulate matter (bioaerosols), the infectivity of viruses when they interact with particulate matter is relatively unknown. At the SOCAAR Seminar on March 7, Dr. Nicolas Groulx, a Postdoctoral Intern in the Department of Microbiology & Division of Infectious Diseases at Sunnybrook Health Sciences Centre and Research Institute and the University of Toronto, spoke about the effects of environmental pollutants on the infectivity of viruses in the air. Continue reading

Linking Tailpipe to Ambient: Atmospheric Evolution of Combustion Emissions

Atmospheric fine particle mass mostly originates from emissions from motor vehicles, wildfires and other combustion processes. When emissions are exposed to oxidants and sunlight, they evolve chemically and physically to generate secondary particulate matter. Dr. Allen L. Robinson, Head of the Department of Mechanical Engineering at Carnegie Mellon University, shared results from their investigations of atmospheric evolution of emissions at the SOCAAR Seminar on February 1, 2017. Continue reading

Sources of Fossil Fuel and Biomass Burning Black Carbon in Ontario

Source: Toronto Star

Black carbon (BC) particles are generated through incomplete combustion processes including combustion of fossil fuels and biomass. These two sources are most commonly from vehicles and residential wood burning for heating. BC has an overall warming effect on the global climate and long-term exposure to it has been associated with cardiopulmonary mortality.

Dr. Robert Healy, Senior Environmental Officer at The Ontario Ministry of the Environment and Climate Change, spoke about the Ministry’s work on assessing the sources of fossil fuel and biomass burning black carbon in Ontario at the SOCAAR Seminar on November 30th, 2016. Continue reading

Organic chemistry associated with Oil Sands Production: From gas phase acidity to secondary organic aerosol formation

Photo source: Wikipedia

The Athabasca deposit in Alberta is the largest oil sand in the world and is a powerful source of Canadian energy. Over the last decade a lot attention has been paid to the environmental impacts of oil sands production. Primary emissions associated with oil sands activities have been the focus of past research but less is known about the reaction products of these emissions to the atmosphere. In the SOCCAR Seminar held on September 14, Dr. Liggio, a research scientist at Environment and Climate Change Canada’s Air Quality Research Division, presented his research on the formation of organic acidity and secondary organic aerosol from oil sands activities. Continue reading

Are lower levels of CO2 but higher black carbon emissions worth the climate trade-off of fuel-efficient engines?

The adoption of fuel efficient engines like the spark ignition gasoline direct injection (GDI) engine has gained popularity recently because of increasing regulations on CO2 emissions from fuel combustion. In 2011, the United States Corporate Average Fuel Economy standards tightened to reduce CO2 emissions. Between 2009 and 2015 sales of new vehicles with GDI engines have increased from five to 46 per cent in the United States, as an alternative to the traditional port fuel injection (PFI). It’s projected that by 2020 over 50 per cent of vehicles will be equipped with GDI engines.

New research from the University of Toronto’s Faculty of Applied Science & Engineering show how GDI engines may emit lower levels of CO2 but more black carbon, a climate-warming pollutant. Continue reading

Bridging cloud condensation nuclei activity and volatility of oxidized organic aerosol

In SOCAAR seminar held on April 6th Dr. Shunsuke Nakao, Assistant Professor at Clarkson University presented a theoretical framework used to study the aging of atmospheric organic aerosol.

Organic aerosol change (i.e. oxidize) as they age in the atmosphere and are nuclei for cloud formation. Having an understanding of the change in cloud condensation nuclei (CCN) activity of organic aerosol as they evolve overtime can be used to identify the impact of organic aerosol on the climate. Continue reading

Air quality co-benefits of climate policy

Air pollution is the leading global environmental health risk factor according to the World Health Organization. Implementing policies that reduce greenhouse gas emissions can also reduce the outdoor levels of air pollutants that harm human health by targeting the same emission sources. Dr. Rebecca Saari, an Assistant Professor at the University of Waterloo, presented the relationship between climate policies and health co-benefits at the SOCAAR seminar held on March 2, 2016. Continue reading

Chronic Exposure to Atmospheric Secondary Organic Particulate Matter Enhances Airway Hyper – responsiveness to Methacholine

It’s well known that exposure to air pollution increases the likelihood and health problems linked to cardiorespiratory diseases. Air pollutants consist of a mixture of gases and particulate matter such as secondary organic aerosols (SOA). SOA are formed through the oxidation of natural sources like plants and trees, as well as from industry emissions like naphthalene. Continue reading

Measurements and Modeling of Ultrafine Particulate Matter in California

Photo source: Berkeley Lab’s Environmental Energy Technologies Division

Toxicological studies have consistently found that ultrafine particles are potentially harmful. Yet only recent epidemiological studies have been able to link ultrafine particles to negative public health effects. The difficulty in finding effects in epidemiological studies may be in part because of the population exposure metrics used in previous studies. In the December 2 SOCAAR Seminar Dr. Michael J. Kleeman, a professor at UC Davis’ Department of Civil and Environmental Engineering, presented 15 years of research on the measurements and modeling of ultrafine particular matter in California. Continue reading

Real-time characterization of soot particles

Soot particles are seen everywhere from city centres to the Alps. There’s ongoing debate on the nature and dynamic evolution of these particles in atmosphere. Soot are light-absorbing, chemically and morphologically complex particles that contribute to air pollution and can have negative health effects. Soot particles are emitted from flames and engines and are highly regional pollutants. Continue reading