#0149 Pulmonary disorder induced by cross-linked polyacrylic acid
Cross-Linked Polyacrylic Acid May Cause Lung Disorders
From foods and shampooes to paints and pharmaceuticals, organic polymers appear in a wide variety of daily-use products. Cross-linked polyacrylic acid (CL-PAA), a polymer synthesized from acrylic acid monomers, is one such polymer whose absorbency and viscosity makes for a wide range of applications.
Unlike inorganic polymers, exposure to organic polymers like CL-PAA is presumed to be safe. In the recent past, however, some cases of allergic reactions and interstitial pneumonia following exposure to organic polymers have been reported. while these reports do not directly associate organic polymers with inflammatory effects, they suggest that the inhalation of organic polymers may be linked to lung diseases.
Against this backdrop, researchers from Japan conducted a study to identify the inflammatory potential of CL-PAA and the mechanism that may lead to lung disorders. They used a rat model in their study and emulated exposure to CL-PAA by delivering the polymer directly to the rat’s trachea via intratracheal instillation.
The effects of exposure were examined for two CL-PAA doses, with rats receiving distilled water used as controls for comparison. To better understand the long-term and short-term effects of exposure to CL-PAA, lung fluids and tissues from rats were examined after different periods of exposure.
The researchers observed an increase in the concentration of chemokines (small proteins that regulate immune response) along with an increase in the number of neutrophils( immune cells playing an essential role in the inflammatory response). Offering a possible mechanism of inflammation, the researchers suggested that the chemokines could be involved in the movement of neutrophils to the lungs upon CL-PAA exposure.
Moreover, the researchers observed a sustained increase in the concentrations of several other inflammatory markers, which indicated the presence of infection and inflammation. Lastly, observation of lung tissues under a powerful microscope revealed fibrotic and inflammatory changes, occurring as quickly as 3 days after CL-PAA exposure and continuing for up to 6 months after exposure.
These results, thus, suggest that CL-PAA may be associated with inflammogenic and fibrotic effects. While the exposure was induced non-physiologically, the outcomes provide evidence of the inflammatory and fibrotic potential of CL-PAA.
Link to original journal article:
https://academic.oup.com/joh/article/64/1/e12369/7249454
Title of the paper:
Pulmonary disorder induced by cross-linked polyacrylic acid
Authors:
Yasuyuki Higashi, Yasuo Morimoto, Chinatsu Nishida, Taisuke Tomonaga, Hiroto Izumi, Ke-Yong Wang, Hidenori Higashi, Ryohei Ono, Kazuki Sumiya, Kazuo Sakurai, Kei Yamasaki, Kazuhiro Yatera
