By Tyler Haughn
Highways offer convenience but they come at a heavy price. The air and noise pollution from all those vehicles creates dangerous conditions for communities living, working or going to school near a highway.
Long-time Somerville resident Ellin Reisner, CAFEH Director Douglas Brugge and other researchers involved in the CAFEH studies are exploring different options to reduce air pollution around Interstate 93 in east Somerville. One approach involves installing portable air purifiers in residential homes dotted along Interstate 93. Air purifiers have already been installed in different parts of the Greater Boston area to determine how much air pollution highways cause.
The research is promising so far but Reisner said she is fully aware that these homes would need to be updated before air purifiers can eventually be introduced.
“The tricky part is a lot of the housing in Somerville is older so it would need to be retrofitted before any air purifiers could be installed,” she said.
Brugge has also spent time researching the importance of air filtration systems inside homes.
“A lot of housing near the highway doesn’t have an existing air handling system,” he said.
Brugge and collaborating researchers are currently on their fourth study designed to assess the benefits of installing portable air purifiers in residential homes. He said the evidence is promising so far.
Brugge also works closely with elected officials in Somerville by advising on regulatory matters. This includes promoting the use of more efficient air filters that can trap ultrafine particles. He added that bureaucratic challenges have been a stumbling block so far.
“The state has a single building code,” Brugge said. “Cities can’t just change and do something different than that building code. They’re subsumed under the state building codes.”
This means Somerville cannot enforce a requirement for homeowners to install better ventilation near Interstate 93 if the rest of the state does not.
Scientists are turning their attention to HEPA air filters to close this gap caused by inconsistent state legislation. Researchers say HEPA filters and other kinds of portable air purifiers may have the ability to significantly reduce indoor exposure to air pollution for a much cheaper cost.
Scott Hersey, an environmental engineer at Olin College of Engineering, said it makes more economical sense to prioritize air-proofing homes instead of soundproofing. He said it would cost less than $1,000 to air-proof a single home while soundproofing costs tens of thousands of dollars per household.
HEPA filters are mechanical air filters that have the potential to remove up to 99.7% of airborne particles inside homes. HEPA air purifiers improve air quality indoors by reducing ultrafine particles and common allergens like dust, pollen and mold spores. All of this goes a long way towards reducing the prevalence of asthma and seasonal allergy symptoms.
“You can reduce your exposure to particles by anywhere from 40% to 92%,” Hersey said. “This comes out to an average of around 60% to 65% if you run a HEPA air purifier. That’s really effective.”
The need to identify and develop effective ways to lower air pollution is urgent. Somerville is not the only place to experience high air and noise pollution levels. Communities in East Boston, Winthrop and Chelsea are also subjected to high amounts of ultrafine particles and other types of pollutants.
Hersey has contributed to a growing body of work compiled by several Boston-area universities which shows that exposure to ultrafine particles can lead to heart attacks and strokes. The research also highlights which communities are more exposed to these extremely tiny particles: low-income residential areas located near highways and the Boston Logan International Airport.
The price range for HEPA filters is the only factor Hersey said could prevent some families from being able to purchase them since they are especially needed in Environmental Justice communities, which are typically low-income.
“A quality air purifier costs $600 upfront and costs about $100 a year to operate,” Hersey said. “So that’s not insignificant in terms of price but it’s really effective if you can afford it.”
Hersey said environmental justice communities experience higher concentrations of pollution because of historical inequities. These disparities often mean environmental justice neighborhoods have disproportionate healthcare access, lower quality housing and less protection from pollutants. The current political landscape only strengthens this unbalanced power dynamic.
“People in environmental justice communities tend not to have as much voice or political clout to advocate for clean air,” Hersey said. “They tend not to have disposable incomes to get things like HEPA air purifiers to reduce their exposure indoors.”
This is where the work of Hersey and other researchers comes into play. He specializes in working alongside communities by providing the scientific know-how and technology to improve air quality. Past projects have focused on building low-cost sensors, ensuring air quality data is accessible to at-risk communities and improving access to technologies that can improve air quality.
Much of Hersey’s time has focused on working with communities in East Boston by providing access to real-time local data so residents can understand how much pollution they are being exposed to at any given time. Community building is a foundational part of his research framework.
“There is another form of research that’s necessary and that is getting communities the direct support they need to achieve better air quality while they’re waiting for regulatory pathways to play out,” Hersey said. “Regulatory pathways to reduce your exposure along the Somerville I-93 corridor might take 10, 20, or even 40 years. In the meantime, there’s a huge amount of exposure that’s happening, and those communities need access to tools to reduce their exposure.”
Hersey said more research teams should prioritize helping communities instead of using them to gather the necessary data. Not enough research grants consider the negative effects this kind of approach has on communities.
“What happens too often is that community groups don’t really have much say in what’s going on in the research,” Hersey said. “They may be part of a planning process or might be recipients of research outputs, but don’t have any real power in the decision-making process. The things that are generated from the research are not for them. They’re for the academic community. They’re for publishing papers.”
Hersey uses low-cost air quality sensors developed by QuantAQ, an air quality company based in Somerville. The sensors are used to detect particulate matter (PM) all the way down to PM 2.5, which is the smallest type of particulate matter currently regulated by the Environmental Protection Agency.
Hersey and his team established an air quality monitoring network in 2019 to record pollution levels in communities around East Boston, Winthrop and Chelsea near the Boston Logan International Airport.
“They’re running 100% of the time,” Hersey said. “They’ve been running for a couple of years at this point. They provide real-time air quality data to those communities and they can access the data on their phones to see what it’s like.”
David Hagan, the co-founder of QuantAQ, said HEPA air filters are the best way forward to prevent air pollution from affecting more disenfranchised communities.
“We spend most of our time indoors and you generally have a lot more control over your indoor environment,” Hagan said. “With HEPA filter interventions, even if this stuff [air pollution] is coming indoors, it’s getting pulled out of the air pretty quickly.”
QuantAQ builds cost-effective air quality sensors and operates a software platform that manages large sensor networks. The company works across a variety of sectors and provides its services to businesses, governments and community stakeholders.
“We’re building these sensors that are far cheaper than the status quo and we think work as well,” Hagan said. “And we also make the data analysis and all of that far easier by building all of these software tools. This helps the people making the measurements and making the decisions since they get the data they need. Then they can make their decisions or disseminate it whatever way they want.”
Hagan blends technical expertise in computer science with his knowledge of atmospheric chemistry to try and improve air quality in Somerville and across the world. This is a major part of the work being done at QuantAQ.
“We do a lot of work with source apportionment, which is basically trying to identify where different types of pollution came from,” Hagan said. “Those algorithms are just inherently heavier and harder to run so they require more computing power. We are always trying to bridge together these new algorithms and machine learning with what we know about how the air works. It is really powerful.”
Hagan and Hersey share similar outlooks when it comes to the role research should play.
“We want to actually make meaningful long-term change,” he said. “We eventually want to put out a million air quality sensors.”
In the meantime, Hersey said he plans to continue advocating for human-centered research while helping communities to take charge of their health and futures.
“There is a need for researchers to be dedicated to that kind of work that gives communities real decision-making power and agenda,” he said.
