New technology allows scientists to detect nano and microplastics in water
The topic of microplastics and nanoplastics is prevalent now more than ever with the recent developments of technology that detected thousands of tiny bits of plastic in common single-use bottles of water. Recently, a team of researchers at Columbia University, developed a new stimulated Raman scattering (SRS) approach to detect micro-and nanoplastics (1).
The science behind this research is incredibly novel and would inherently be expensive to duplicate. Currently, no commercial drinking water testing exists for nanoplastics, but we can use the evidence established to draw some assumptions related to filtration performance.
Microplastics vs Nanoplastics
Microplastics and nanoplastics are both tiny pieces of plastic, but they differ in size.
Microplastics are tiny plastic particles generally ranging from 5 mm to 1 micron in size. They can be intentionally made for specific uses, like microbeads in cosmetics, or can result from when larger plastic items break down due to weathering, material breakage, or mechanical forces. Additionally, microplastics can originate from synthetic fibers shedding off textiles during washing and use.
In comparison, nanoplastics are even smaller than microplastics, measuring less than 0.1 μm (micrometer). Nanoplastics can originate from the degradation of larger plastics, as well as from the breakdown of microplastics themselves. They are at the nanoscale, which means they are smaller than what can be seen with a standard microscope and often require more advanced techniques to be observed.
Using the new SRS approach developed to detect micro- and nanoplastics, researchers determined that they could spot particles smaller than 1 μm (1).
Microplastics and Nanoplastics in drinking water
83 percent of tap water worldwide contains microplastics, according to an in-depth study by State University of New York at Fredonia. The United States has the highest presence: 94 percent of U.S. tap water is contaminated with microplastics (2). Microplastics have also found their way into bottled water: microplastics were found in 93 percent of 11 popular water bottle brands around the world (3).
Most recently, a research team led by Drs. Wei Min and Beizhan Yan of Columbia University and reported by the National Institute of Health used a novel technique to identify 240,000 tiny pieces of plastic in a 1L water bottle of which 90% were estimated to be nanoplastics. The depth and impact of nanoplastics in drinking water is still largely unknown.