• Dr. Timothy Smith

Microplastics—Found in People Even Infants


Photo Source: Pixabay


The loving act of giving a baby a warm bottle of formula happens every day in millions of homes around the world. Still, research shows that babies may also get, along with the milk, an invisible contaminant known as microplastics. Microplastics, small pieces of plastic under five millimeters long, have found their way to the farthest reaches of the Earth, from remote Antarctica to the bottom of the oceans (NOAA) and even into our bodies.


Scattered by wind and water currents, tiny fragments of plastic from various sources such as water bottles, single-use medical devices, and the thousands of other plastic products and byproducts made over the past seventy years have dispersed to the four corners of the Earth. We also find them in living things. According to a review in The International Journal of Environmental Research and Public Health, the global distribution of microplastics marks a new era in geological sediment analysis. Geologists now call it the Plasticine Period. (nih.gov)


Just as sand results from the relentless pressure of erosion on rocks, microplastics result from the breakdown of plastic products through erosion, sunlight, heating, and friction. Many types of action create microplastics at home or work, such as feet walking on a carpet containing plastic fibers, the sleeve of a polar fleece resting on an armchair, or the heating and cleaning of plastic food and beverage containers. Researchers examined plastic baby bottles in an alarming paper published in Nature Food. They found that babies drinking formula from polypropylene plastic bottles consume up to 16,200,000 microplastic particles per liter (33 oz) of formula. (nature.com). They concluded that the heating and cleaning of the bottles produced the most polypropylene particles. Research has shown that plants and animals that we eat contain microplastics that they have accumulated from their environment. For example, research summarized in a UN report illustrated the presence of microplastics in fruits and vegetables, meat, salt, bottled water, and seafood such as fish, mollusks, and crustaceans. (cbd.int) Studies have shown that animals eating other animals, plants, or plankton absorb microplastics from their prey.


Recent studies demonstrate that microplastics can penetrate the human digestive tract and are found in the blood. In a paper published on March 24, 2022, titled “Discovery and quantification of plastic particle pollution in human blood,” Dutch scientists found microplastics in human blood using sophisticated analytical tools. (sciencedirect.com) Analyzing blood from twenty-two healthy volunteers revealed four types of microplastics, including polyethylene and polystyrene. The most widely used plastic in the world, polyethylene, constitutes many products from food wrap to detergent bottles. The average individual in the study had 1.6 micrograms of microplastics per ml of blood. Interestingly, they looked for polypropylene, another popular plastic material, but found it below the level of detection for their technique.


Naturally, we must ask if these microplastic pollutants threaten human health, but insufficient research in this area leaves us without definitive answers. However, mounting evidence in other species indicates potential risk. Authors reviewed the literature and published a paper titled “A Detailed Review Study on Potential Effects of Microplastics and Additives of Concern on Human Health.” (nih.gov) Although inert in many respects, plastics can harm one’s health in several ways. Some plastics contain chemicals that can leach out of the plastic as it erodes. Polycarbonate plastics use BPA in the production of popular food containers. BPA has toxic properties for the endocrine system, which regulates growth and reproduction in animals, including humans and links to childhood obesity. Microplastics can also act as rafts for other chemicals such as poisonous heavy metals such as lead and mercury or as rafts for microorganisms. Additionally, tiny plastic fragments can get into tissue and cause chronic irritation the way asbestos does. Such chronic inflammation can lead to cancer. (nature.com)


Human creativity and the golden age of chemistry in the middle of the 20th century gave us plastics that have impacted every aspect of life, from easily transportable food and water containers to strong, lightweight materials used in manufacturing automobiles and airplanes to tools and computers. Just as stone erodes into sand, plastics degrade through physical action and sunlight into smaller and smaller particles. These tiny particles, or microplastics, have contaminated the entire globe and our bodies. For example, baby formula mixed in polypropylene plastic bottles contains millions of microplastic particles. Microplastics do not just pass through but circulate through our bodies in the blood. Elements of plastic such as BPA have known toxic properties, but microplastics' effects on human health need more study to understand the implication fully. But in the meantime, glass baby bottles need to make a comeback.



Dr. Smith’s career in scientific and information research spans the areas of bioinformatics, artificial intelligence, toxicology, and chemistry. He has published a number of peer-reviewed scientific papers. He has worked over the past seventeen years developing advanced analytics, machine learning, and knowledge management tools to enable research and support high-level decision making. Tim completed his Ph.D. in Toxicology at Cornell University and a Bachelor of Science in chemistry from the University of Washington.



You can buy his book on Amazon in paperback and in kindle format here.