E-Mail 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.