Entrepreneurs / Startups / Women in tech

These Penn grads are trying to reduce microplastic pollution in water, one load of laundry at a time

As young women in the startup industry, Julia Yan and Sarah Beth Gleeson of Baleena said they’re learning about confidence and how to filter through feedback.

Julia Yan and Sarah Beth Gleeson. (Courtesy Baleena)

In the world of entrepreneurship, you’re less likely to run into a founding team of 20-something women.

Yet after four years of studying material sciences and engineering at the University of Pennsylvania, Sarah Beth Gleeson, Julia Yan and Shoshana Weintraub chose to take the leap and start their own company, Baleena, as fresh graduates.

The cofounders, who were recently named to Forbes’ 30 Under 30 list in the energy category, did their senior capstone project together on microplastic pollution. In their research, they learned that 35% of microplastic pollution in the ocean came from laundry.

They wanted to find a way that college students could tackle microplastics pollution, so they came up with the idea for a product that would filter pollutants in the washing machine, COO Gleeson told

“In undergrad, we were really drawn to bio-inspired design, and we really want to look to nature to solve a problem that exists today,” CEO Yan said. So the founders looked to sea sponges and other natural filters.

Growing a sustainability-minded startup

Gleeson, Yan and Weintraub graduated from Penn in 2022 and won the Penn President’s Sustainability prize — and an accompanying $250,000 — that spring to support working on their company full-time for a year. During this first year, the team was based at the Pennovation Center where they had access to Pennovation’s resources, participated in its accelerator and won the 2022 pitch day.

“It was really like a first vote of confidence from our university that kind of inspired us to become entrepreneurs for the first time,” Yan said.

Sarah Beth Gleeson and Julia Yan. (Courtesy Baleena)

Now based at CIC in University City, Baleena is developing a consumer product that attaches to the inside of a washing machine drum and filters microfibers in the water. The product has a hard outer shell and soft inner filter. Gleeson said they’re at a prototype stage for this filter, but so far have been seeing positive test results.

The team has broadened its vision to look at microplastic pollution throughout the entire fashion supply chain, not just laundry. Ultimately, they want to work with large companies and brands to reduce pollution in textile manufacturing, Gleeson said.

Baleena raised $460,500 from a pre-seed round in June 2023. Some of this funding came from grants and prizes, but some was awarded by the gener8tor Sustainability Accelerator, which the company completed last spring.

The company plans to start raising a seed round this March, Yan said. Weintraub left the company to pursue her Ph.D. in engineering, so part of this funding round will go toward expanding the team.

On being young entrepreneurs

During her college career, Yan interned with an early-stage healthtech startup and loved the environment. She thought then that she would pursue a startup eventually — but didn’t think it would happen so quickly.

“I think it was like the perfect opportunity for us to really get the chance to explore and fail and learn a lot,” she said. “And so, while it was earlier than I intended, I think it definitely was the right move for me.”

Gleeson, however, was more interested in pursuing research after college and didn’t interact with business or startup programming much while she attended Penn. Now that she’s in the startup world, she’s come to appreciate the industry and how it interacts with other fields.

Starting a company right out of college and being an all-women founding team has been a lesson in confidence building, Yan said. They have had to learn how to listen to feedback, take what seems valuable and leave what doesn’t.

Yan and Gleeson said they offer a fresh perspective to the startup world, both as women and as recent college grads.

Yan’s advice for other young women in a similar position: Don’t be intimidated by external opinions if you’re passionate about your business.

Sarah Huffman is a 2022-2024 corps member for Report for America, an initiative of The Groundtruth Project that pairs young journalists with local newsrooms. This position is supported by the Lenfest Institute for Journalism.
Companies: Pennovation Center / University of Pennsylvania

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