Cornstarch sanitary pads cheap enough to avoid tonnes of ocean plastics

A new lifecycle study published in IOP Publishing’s journal Sustainability Science and Technology has discovered a promising alternative to plastic sanitary products, potentially leading to far reduced sanitary waste. Sanitary pads made with cornstarch are 17 times more environmentally friendly compared to plastic equivalents.

The high concentration of plastic in disposable products is a direct threat to the environment. An estimated 200,000 tonnes of sanitary products are disposed of every year, and the vast majority of them end up in the ocean.

Key statistics:

• Sanitary pads made with cornstarch are 17 times more environmentally friendly compared to plastic equivalents.
• Each menstruating person uses approximately 120kg of menstrual products in their lifetime
• Sanitary pads are made from 90% plastic, corresponding to about 4 plastic bags
• 55,000 tonnes of plastic sanitary waste per year ends up in North American bodies of water

Scientists found that, over the course of one year, using a cornstarch derived biodegradable material called polylactic acid (PLA) to create sanitary products reduced environmental impact by 17 times compared to the plastic equivalent. The PLA based pads exhibit lower global warming potential and far reduced toxicity due to the material’s more sustainable manufacturing processes compared to fossil-based plastics.

Even taking into account that the production of PLA contributes to higher land use, the overall renewable sourcing and lower environmental footprint mitigate the environmental impacts, in comparison to disposable plastic products.

Sustainable alternatives to traditional sanitary products remain underused by large companies, as they require commercial quantities to make these high-street products viable and affordable. Cornstarch based products are easily producible and can be scaled so that large companies could use it as an effective and sustainable alternative.

Corn is one of the most widely grown crops in the world and is used for a variety of purposes, including food for humans and livestock, biofuel production, and as a raw material in many industrial products. The global trade of corn involves many countries, making it a significant player in the international trade market and enabling large companies to buy large quantities.

Alice Medeiros de Lima, corresponding author of the study, says: “Research into sustainable sanitary materials has consistently shown that while many alternatives to traditional products exist, the key to widespread adoption lies in ease of production, price and scalability. Given the detrimental effects of plastic based sanitary products on the environment, transitioning to cornstarch- based products can significantly reduce waste and provide a more sustainable solution for the future.”

ENDS

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About the authors
This research was led by Prof. Alice Medeiros Lima from the Department of Chemical Engineering at the Federal University of São Carlos (UFSCar), in collaboration with Prof. Sandra Cristina Dantas from the Federal University of Triângulo Mineiro (UFTM). The study was developed as part of the research line on Sustainable Process Systems Engineering, with a focus on life cycle assessment (LCA) and bio-based alternatives. It involved the contribution of undergraduate students who were actively engaged in research activities and have since progressed to work in major chemical industries in Brazil. The project reflects a shared institutional commitment to advancing sustainable technologies and strengthening academia–industry connections.