U of T professor co-leads global partnership on non-exhaust vehicle emissions

Professor Greg Evans (ChemE, ISTEP) is one of three co-leads on NEXUS, a research consortium bringing together experts from 17 universities across the UK, Europe, North America and Asia, alongside eight public and industry partners. Evans leads alongside Professor Chris Griffiths from the University of Oxford and Professor Ian Mudway at Imperial College London. 

Funded for five years by the UK Medical Research Council, the partnership will build research capacity and deliver evidence to guide health policy and the development of cleaner vehicle technologies. 

The partnership will also support international collaboration through graduate student and postdoctoral exchanges, as well as public, government and industry engagement. 

“Non-exhaust emissions are an emerging global issue,” says Evans.  

“A typical car emits roughly five kilograms of brake and tire material into the environment each year. While these emissions remain largely unregulated, studies have already detected tire-derived antioxidants and brake metals in fish. What we don’t yet know is how they impact human health.” 

With improvements in combustion technology and the shift to electric vehicles (EVs), tailpipe emissions are declining. At the same time, rising consumer demand for heavier vehicles — such as SUVs, pickup trucks and EVs themselves — has driven up the release of non-exhaust particles, which now often exceed exhaust emissions in cities. 

Evans’ expertise stems from his work on air quality through the Southern Ontario Centre for Atmospheric Aerosol Research (SOCAAR) at U of T, which specializes in using advanced instruments and data mining to measure urban air pollution exposure.  

“This research connects with our work on subway air quality, where non-exhaust emissions are the major source,” says Evans.  

“NEXUS will help us understand how these particles affect people and guide the creation of regulations and new technologies with lower emissions.” 

Over the next five years, NEXUS aims to establish research priorities on non-exhaust emissions and elucidate their potential health effects. They also hope to launch pilot projects across disciplines and build a sustainable international network to address this emerging environmental issue. 

The team’s other focus is to influence policy. Europe has introduced the first regulations limiting non-exhaust emissions, and Evans sees opportunities for Canada to follow suit. 

“The potential benefits are significant,” he says.  

“We can help shape regulations in Canada and give Canadian companies a head start in creating vehicle technologies that provide a competitive edge when similar regulations are implemented globally.” 

For Evans, the work is both professional and personal. Having transitioned to electric vehicles years ago, he has noticed an increased need to replace tires compared with past vehicles.  

“This bothers me,” he says.  

“I hope that through NEXUS, and the changes it enables, we’ll be able to mitigate this.” 

Beyond its initial five-year funding, Evans envisions NEXUS laying the groundwork for large, multinational, multidisciplinary research proposals. Communication and results will be shared through webinars, reports, journal publications and a forthcoming LinkedIn page. 

The initiative aims to create opportunities for research exchanges, collaborations across sectors and public engagement activities. 

“The convergence of people from industry, government, NGOs, health, medicine, chemistry and engineering is the best way to implement and lead positive change,” says Evans.