Known as the SHERO pad, it is 100 percent biodegradable, while also thinner and more comfortable than similar products and made of materials that women could grow themselves or find readily available. Developed by Bates and four U. engineering undergraduates, each pad is composed of raw cotton, super-absorbent agarose gel made from brown algae and corn-based material, making them compostable as well.
A 2016 study estimated that nearly 20 billion sanitary pads, tampons and applicators are discarded in North America landfills each year, often taking centuries to decompose. But a reduced environmental impact is only part of the SHERO pad's potential benefit.
Bates said he began working on an early iteration of the pad after SHEVA, a nonprofit group in Guatemala, contacted him about the challenges women and girls in the Central American nation face over of their menstrual periods. Many Guatemalan women stay at home for a week each month because there aren't many affordable, comfortable or accessible feminine care products available.
Many also live in areas lacking public sanitation, Bates said, making it crucial that discarded sanitary pads break down quickly. The SHERO pad takes 45 days to six months to biodegrade completely.
"I hope this product will help empower those women to do what they want in their own communities," Bates said.
The U. team hopes to start testing the invention this year and getting it to U.S. markets and some developing counties by next year — pending Food and Drug Administration approval.
Coming months, Bates said, will be spent fine-tuning the product's adhesives and packaging, conducting market research and creating a cost-efficient way to synthesize the agarose gel.
Several environmentally conscious feminine care products are available in the U.S. Bates said the pad's biodegradable and absorbent hydrogel isn't present in other brands.
Bates said he initially had graduate students working to create super-absorbent biodegradable materials. But after his spilled rice epiphany, he said, he decided to bring undergraduate students into the fold for materials testing — to great success.
Senior Amber Barron said she's been inspired by the socially beneficial potential of the pad.
"I have always been interested in sustainability and am motivated by a sense of what we can do for our planet and the people around us," said Barron, a material science and engineering major. "I value the social aspects of this project, and I love seeing the direct social benefit and impact it can have."
Eventually, Bates wants to open a manufacturing site in Guatemala where women can use the SHERO model to make pads out of locally available materials.