Comparative Analysis of Physical and Polymer Characteristics of Microplastics Detected in Human Colorectal Cancer Samples From the United States and Malaysia
Nur Sakinah Roslan, Yeong Yeh Lee, Sabiqah Tuan Anuar, Ku Mohd Kalkausar Ku Yusof, Teresa A. Brentnall, Lisa A. Lai, Ahmad Ammarluddin Mohd Ali, Yusof Shuaib Ibrahim
Abstract
BACKGROUND AND AIMS: Previous studies have detected microplastics in bowel tissues, but have been limited by small sample sizes. Our study expanded the data collection from two countries at different time points (United States from 1993 to 1999 and Malaysia from 2023 to 2024) with the aim of comparing the physical and polymer characteristics of microplastics found in colorectal cancer samples. MATERIALS AND METHODS: Microplastics were extracted from the tissues using a chemical digestion method of 10% potassium hydroxide, and examined under a stereomicroscope. Further surface morphology and polymeric composition were analyzed with a scanning electron microscope and micro-Fourier transform infrared spectroscopy. RESULTS: Microplastics were detected in all 50 samples (25 from the United States and 25 from Malaysia), with a higher abundance found in the Malaysian samples (32.2 ± 48.14 particles/g) compared to the American samples (25.00 ± 40.57 particles/g). Both population samples exhibited similar shapes, with fibers being the most abundant. American samples have longer microplastics (Category II = 501-1000 µm) than the Malaysian samples (Category I = < 500 µm). Both population samples exhibited surface roughness on their microplastics and similar polymer types including polyethylene (PE), polypropylene (PP), polyamide (PA) and polycarbonate (PC). Acrylonitrile butadiene styrene (ABS) was only observed in the American samples. CONCLUSION: Microplastics are detected in colorectal cancer samples of both populations collected from two different time points but with similar and also distinct physical and polymer characteristics.