Faculty Fanfare: Eliane El Hayek


Two UNM researchers have published an article on microplastics toxicity that was selected as the June 2023 Extramural Paper of the Month by the National Institute of Environmental Health Sciences.


The article, “Photoaging of polystyrene microspheres causes oxidative alterations to surface physicochemistry and enhances airway epithelial toxicity, is a collaborative work between Drs. Eliane El Hayek of UNM’s College of Pharmacy and Eliseo Castillo of UNM’s Department of Internal Medicine and additional collaborators. It is published in the journal Toxicological Sciences.


The work is a collaboration between UNM, UNMHSC, and Oklahoma State University, and considers the health risks posed by human exposure to plastic debris or microplastics. It is part of ongoing research on how the chemistry of miniscule plastic fragments can be altered by environmental factors including ultraviolet light. Such changes, which can also come from humidity or high temperatures, potentially increase the toxicity of the plastics to lung cells. 


El Hayek said the work is important because microplastics can be present in dust, water, and food and can be ingested or inhaled.


As part of the research, commercially available polystyrene microspheres were weathered with ultraviolet light for five weeks.


Researchers exposed lung cells to the aged microspheres as well as to spheres that had not been weathered. Using spectroscopy, researchers saw that the UV exposure affected the particle’s chemical structure. The aged microspheres caused more biological responses in lung cells than pristine microspheres. Responses in the lung cells included a slowing of healing from wounds, alterations in cell metabolism, and an increase in the number of cells in earlier stages of growth and division. The latter is a sign that lung cancer could be forming. 


“Environmental weathering, such as UV light, affects the microplastics’ surface chemistry and reactivity exacerbating their toxicity,” El Hayek said.


“Such processes are of concern given the widespread presence and long persistence of microplastics in the environment where they can get prolonged and continuous exposure to sunlight. The study highlights that understanding the influence of weathering, along with that of size, shape, and chemistry, across the lifespan of plastics may be an important consideration for the types of plastics incorporated into plastic products that people use in their daily life, such as food containers, cosmetics, clothing, etc,” she said.


The publication relates to work El Hayek is doing as part of her 2022 Women in STEM Award, called 

“Fibers Pollution During Critical Periods of Climate Change: an Overlooked Enhancer of Chronic Respiratory Inflammations?” 


That work, which is ongoing, also explores the role of fiber pollution in respiratory inflammation. El Hayek in July 2023 received a pilot award from the New Mexico Integrative Science Program Incorporating Research in Environmental Sciences Center (NM-INSPIRES P30 Center) that will support the funding of her project.


“Daily human exposure to plastic and fiber particles is occurring, yet the toxicological consequences of this exposure are still underestimated,” El Hayek said when the award was announced. “The goal of my project is to develop a novel approach to detecting the enhancement of chronic respiratory inflammations caused by exposure to fiber particles.”