“Indoor air has higher mercury concentration than outdoor air,” says chemistry and biology professor Julia Lu, supervisor of the research team and one of the authors of the study. “As a result, mercury has been reduced or removed from some products that are used indoors, but more steps need to be taken.”
Elemental mercury, a highly toxic substance found in such things as thermometers, batteries and fluorescent lights is liquid at room temperature. If it is not sealed in a container it can evaporate and be carried into the atmosphere. Eventually, it becomes oxidized mercury, which clings to surfaces in the environment. It will also change from inorganic forms to organic forms, which are much more toxic and will accumulate in the food chain.
To measure gaseous elemental mercury (GEM) in the atmosphere in Toronto, the researchers analyzed GEM concentrations at different times of day along major streets and highways, such as Queen Street, Eglinton Avenue, Highway 7 and Steeles Avenue. Twenty-seven underground and surface parking lots throughout the downtown core were also tested, as were five locations within and around Ryerson University’s Kerr Hall.
The researchers made several discoveries. First, they found that in Toronto, the higher the elevation, the higher the level of atmospheric GEM. Second, GEM levels are higher in underground parking lots than in surface lots. Third, GEM levels are higher indoors than outdoors. Fourth, GEM levels are higher in the outside air near building walls. Fifth, GEM levels at pedestrian levels during rush hour and non-rush hour were not statistically different from each other. The final finding, according to Lu, indicates that vehicles are not a major source of mercury to the urban atmosphere.
“There’s no need for alarm among pedestrians because street-level concentrations of elemental mercury aren’t high compared to rural areas. It won’t make you sick right away,” Lu says.
The real danger, she continues, is the future impact of mercury on the planet. Through a process combining long-range transport, chemical conversion, and bio-accumulation, mercury builds up in living organisms and ultimately affects every level of the food chain. This situation poses a serious threat to human and animal life, and the environment. A common example of bio-accumulation is the high levels of mercury in fish and shellfish. Consumption of such fish during pregnancy can pose significant health problems for babies.
More studies are needed to estimate the contribution of urban areas to atmospheric mercury, and the impact of indoor air on outdoor air quality and human health. In the meantime, though, Lu says it’s important to take some action now.
“Mercury can be discovered during building renovations. For example, it can be found in the floor tiles of an industrial building that used mercury or after a mercury spill in an old laboratory. It can be difficult to retrieve. So, our starting point is to get the source of the mercury under control and then reduce indoor levels of it.”
Lu and her team continue to research the presence and impact of elemental mercury, their next objective will be to pinpoint and quantify buildings that are sources of elemental mercury.
The paper’s lead authors are former Ryerson graduate student Elaine Cairns and undergraduate student Kavitharan Tharumakulasingam (a NSERC Undergraduate Student Research Awards recipient), both of whom were supervised by Lu. The research team also included Lu’s former graduate students Irene Cheng and Y. Huang, current graduate student Muhammad Yousaf, Dave Yap of the Ontario Ministry of the Environment and Makshoof Athar, a postdoctoral fellow from the University of the Punjab.
“Source, concentration, and distribution of elemental mercury in the atmosphere in Toronto, Canada” was published earlier this year in the online version of the journal Environmental Pollution. Research funding was provided by the Ontario Ministry of the Environment, the Natural Sciences and Engineering Research Council of Canada, and the Canada Foundation for Innovation. Support for Athar’s work was provided by the Higher Education Commission of Pakistan.
Ryerson University is Canada’s leader in innovative, career-oriented education and a university clearly on the move. With a mission to serve societal need, and a long-standing commitment to engaging its community, Ryerson offers more than 100 undergraduate and graduate programs. Distinctly urban, culturally diverse and inclusive, the university is home to 28,000 students, including 2,000 master’s and PhD students, nearly 2,700 tenured and tenure-track faculty and staff, and more than 130,000 alumni worldwide. Research at Ryerson is on a trajectory of success and growth: externally funded research has doubled in the past four years. The G. Raymond Chang School of Continuing Education is Canada's leading provider of university-based adult education. For more information, visit www.ryerson.ca
Johanna VanderMaas | Newswise Science News
Research offers clues for improved influenza vaccine design
09.04.2018 | NIH/National Institute of Allergy and Infectious Diseases
Injecting gene cocktail into mouse pancreas leads to humanlike tumors
06.04.2018 | University of Texas Health Science Center at San Antonio
Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.
Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...
Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.
The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...
Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.
Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...
In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...
In an article that appears in the journal “Review of Modern Physics”, researchers at the Laboratory for Attosecond Physics (LAP) assess the current state of the field of ultrafast physics and consider its implications for future technologies.
Physicists can now control light in both time and space with hitherto unimagined precision. This is particularly true for the ability to generate ultrashort...
13.04.2018 | Event News
12.04.2018 | Event News
09.04.2018 | Event News
19.04.2018 | Materials Sciences
19.04.2018 | Physics and Astronomy
19.04.2018 | Physics and Astronomy