CLIMATE ACTIVISTS opposing the expansion of the largest private jet airport in New England are turning their ire on a venture capitalist heading the companies that proposed the expansion.

Jeffrey Leerink, best known for his investment in health care and life sciences, is also a principal of North Airfield Ventures and Runway Realty Ventures, two firms that along with the Massachusetts Port  Authority are proposing to build 27 more hangars for private jets at Hanscom Field in Bedford. 

“From now on, Jeffrey Leerink is going to be attached to this project and the harms that are going to be caused by the expansion of Hanscom,” said Chuck Collins, one of the organizers of a protest that took place on Thursday outside of Leerink’s office in downtown Boston.

Leerink is a founder and owner of an investment bank that mainly funds clients in the biotech, healthcare, and life sciences industries. At the protest, activists pointed out what they consider to be a hypocrisy in Leerink’s self-positioning as someone who has created a specialized firm in health care to “make a difference to patients” and as someone who is investing in a project that will, according to them, raise carbon emissions and contribute to global warming, a public health issue.

“As we have been saying all day, he built his legacy investing in health care. Don’t burn it down investing in catastrophic climate change,” said Alex Chatfield, another organizer of the protest.  

Leerink couldn’t be reached for comment Thursday.

Critics of the Hanscom expansion, including state lawmakers, local officials, and climate advocates, have raised concerns that an expansion will encourage the use of more private jets and lead to higher carbon emissions at a time when the state is working to aggressively curb emissions. 

The expansion plan proposed by Massport is currently undergoing a state  environmental review to assess the impact the project will have on public health and fossil fuel emissions.  

A DC-based think tank, the Institute for Policy Studies, released a report analyzing 18 months of flight data on private jet flights from Hanscom Field. The report estimated that, over an 18-month period, private jets accounted for 106,676 tons of carbon emissions. Private jets emit at least 10 times more pollutants per passenger than commercial airplanes. The report also found that about half of all private jet flights were recreational or luxury travel.

The protest on Thursday was a followup to a rally that the climate coalition, Stop Private Jet Expansion at Hanscom or Anywhere, held at the State House last month where they urged Gov. Maura Healey to stop the expansion project. They brought 10,000 signatures to support their petition to the governor.

Now activists are appealing to the private investors in the project.

“We want [Leerink] to know we are keeping an eye on him,” said Collins. “We’re not just watching Massport. We’re not just watching the governor. We are watching Jeffrey Leerink as the driving investor of this project and how he acts.”