The snow may be melting, but it is leaving pollution behind in the form of micro- and nano-plastics according to a McGill study that was recently published in Environmental Pollution. The pollution is largely due to the relatively soluble plastics found in antifreeze products (polyethylene glycols) that can become airborne and picked up by the snow.
The researchers used a new technique that they have developed to analyze snow samples collected in April 2019 in Montreal for both micro- and nano-sized particles of various plastics. The McGill technique is orders of magnitude more sensitive than any of the other current methods used for tracing plastic in the environment. It allows scientists to detect ultra-trace quantities of many of the most common soluble and insoluble plastics in snow, water, rainfall, and even in soil samples once they have been separated - down to the level of a picogram (or one trillionth of a gram). It is based on using nano-structured mass spectrometry and, unlike other techniques currently in use, the new technique is both recyclable and based on sustainable practices.
"It is important to be able to detect even trace quantities of plastics in the environment," says senior author, Parisa Ariya, from McGill's Departments of Chemistry and Atmospheric and Oceanic Sciences. "Though these plastics may be harmless in themselves, they can pick up toxic organic matter and heavy metals from the environment, which can damage human cells and organs."
The first author, Zi Wang, a PhD Candidate at McGill adds, "Our hope is that this new technique can be used by scientists in different domains gain key information about the quantity of micro- and nano-plastics in urban environments in order to better address their impacts on the ecosystem and on human health."
To read: "Advances in Ultra-Trace Analytical Capability for Micro/Nanoplastics and Water-Soluble Polymers in the Environment: Fresh Falling Urban Snow", by Zi Wang, Nadim K. Saadé, and Parisa A. Ariya in Environmental Pollution.
The research was funded by the Natural Science and Engineering Research Council of Canada (NSERC), National Research Council Canada (NRC) and Environment of Climate Change Canada (ECCC).
About McGill University
Founded in Montreal, Quebec, in 1821, McGill University is Canada's top ranked medical doctoral university. McGill is consistently ranked as one of the top universities, both nationally and internationally. It is a world-renowned institution of higher learning with research activities spanning two campuses, 11 faculties, 13 professional schools, 300 programs of study and over 40,000 students, including more than 10,200 graduate students. McGill attracts students from over 150 countries around the world, its 12,800 international students making up 31% of the student body. Over half of McGill students claim a first language other than English, including approximately 19% of our students who say French is their mother tongue.