NDSU professor receives NSF Award to help manage PFAS in compost

Syeed Iskander, NDSU assistant professor of civil, construction and environmental engineering, has received a U.S. National Science Foundation award of $419,850 for his project “Mechanistic Insights into Polyfluoroalkyl substances Distribution and Leaching in Compost – a Unique Environmental Matrix.”

The research project aims to better understand how harmful chemicals called PFAS (per- and polyfluoroalkyl substances) move, change and leak out in compost. Compost is becoming more critical in waste management, especially with new laws encouraging less organic waste in landfills. It’s crucial to know how PFAS behave in compost to keep it safe for use.

“PFAS are persistent environmental pollutants linked to health risks, and their presence in compost raises concerns about human exposure and environmental dissemination,” Iskander said. “Receiving this NSF award is a recognition of the importance and innovation of our research on PFAS in solid waste management processes. It provides critical funding to investigate how these harmful chemicals move in compost, a widely used organic waste product. This award allows us to explore mechanistic insights into PFAS leaching from mature compost, and the knowledge will help us develop safer composting practices.”

Iskander said the research goal is to make composting safer by understanding how PFAS move through compost.

“We want to identify the best storage methods for mature compost to reduce PFAS contamination. The findings will help develop simple treatment methods, like compost washing, to remove PFAS before compost is used,” Iskander said. “We'll also share science-based guidelines with regulators and teach compost facilities and the public how to prevent PFAS from entering compost in the first place. By doing this, we can keep composting as an eco-friendly way to recycle organic waste while protecting people's health and the environment. This work fills important gaps in waste management science and supports NSF's goal of creating research that benefits society.”

PFAS are thousands of human-made chemicals used in consumer products, dating back to the 1940s, including water-resistant fabrics and carpeting, cleaning products, paints and fire-fighting foams. According to the FDA website, the widespread use of PFAS and their persistence in the environment means that PFAS from past and current uses have resulted in increasing levels of air, water and soil contamination, leading to negative impacts on human health.

Iskander’s team has found PFAS contamination in yard-waste compost. That research found that PFAS have a unique distribution pattern in a mature compost pile with a higher concentration at deeper layers.

“Our team discovered concerning levels of PFAS in yard waste compost, along with distinctive distribution patterns,” said Biraj Saha, an NDSU Ph.D. student who led the preliminary study which culminated in the NSF award. “With this NSF support, we will elucidate the mechanisms driving PFAS movement in compost and focus on the implications for agricultural systems.”

Key factors influencing PFAS mobility include dissolved organic matter, moisture and temperature gradients.

“This project will study three key aspects of PFAS behavior in compost,” Iskander said. “First, we'll examine how compost characteristics like porosity, organic matter content and temperature influence PFAS movement during rainfall. Second, we'll investigate how freeze-thaw cycles in cold climates affect PFAS release from compost. Finally, we'll analyze differences in how linear and branched forms of PFAS move through compost.”

“This important research addresses a growing public health concern and exemplifies the kind of innovative, real-world impact our faculty are making,” said NDSU Dean of Engineering Alan Kallmeyer. “By uncovering how PFAS chemicals behave in compost, this project will help protect our environment, inform policy and improve the safety of a practice used by millions of households. We’re proud to support Dr. Iskander’s work that combines cutting-edge science with meaningful outreach and student engagement.”

Freeze-thaw cycles happen when the air temperature drops low enough to freeze water and then increases enough for it to thaw again. In North Dakota, Iskander said the colder climate makes freeze-thaw cycles a major driver of PFAS leaching from compost because of their downward movement from ice thaw and their chemical properties. This research will work to improve compost management practices at local facilities.

“By understanding PFAS risks, the project will help protect the state’s agricultural sector, where compost is widely used to enrich soils, ensuring safer crops and livestock,” Iskander said. “Additionally, community outreach efforts — such as distributing informational leaflets at Fargo composting sites — will raise awareness and reduce PFAS contamination in yard waste. Beyond the state, the findings will inform national composting regulations and industry best practices, including techniques like compost washing to mitigate contamination. The research also contributes to broader environmental health by reducing PFAS spread into water and soil systems.”

This research is funded by NSF Award #2530466.