When plastic was introduced in the 20th century, it revolutionized nearly every industry. However, it was little known how this wondrous invention would go on to pervade every part of our lives. From landmasses and deep oceans to living organisms, the water bottle in your hand and the water within have not even spared the infamous chicken nuggets!
The fate of plastics after their “intended” use is a serious cause for concern. Their indiscriminate production and disposal have led to widespread pollution of our terrestrial and aquatic ecosystems, as plastics can take hundreds of years to break down. Plastics may exude ‘resilience’ and ‘persistence’, traits we admire in people, but in our environment, they have overstayed their welcome.
As larger plastics break down through natural or artificial processes, they generate microplastics – particles smaller than 5 millimeters, and even smaller nanoplastics that are invisible to the naked eye. Microplastics can be found in common household and personal care products such as glitter, microbeads, and microfibers. Because of their extremely small size, detecting these particles often requires specialized laboratory techniques.
While microplastics can enter the body through skin contact and inhalation, the most common route of microplastic exposure is through ingestion. The idea of plastic quietly becoming an uninvited ingredient in our food is particularly disturbing. After all, we are what we eat. According to a study published in the Environmental Science & Technology journal2, an average person consumes up to 52,000 microplastics per year. In a 2020 study3, researchers detected microplastics in fruits and vegetables purchased from local markets in Catania, Italy. Of the tested samples, apples and carrots had the highest levels. Microplastics have also been found in protein-rich food products, including animal- and plant-derived proteins such as seafood, pork, beef, chicken, and tofu4, as well as in salt, tea, and bottled water. In fact, a recent study found that a liter of bottled water contained 240,000 nanoplastic particles5.
It is not just what we eat; how we store, handle, and consume food may also aggravate this problem. Studies have shown that reusable plastic food containers heated in the microwave for just three minutes could release up to 4.22 million microplastic particles and 2.11 billion nanoplastic particles from a single square centimeter6. Moreover, storing food at room temperature or in refrigeration may introduce micro- and nanoplastics into food. Even the use of plastic (polyethylene)-coated paper cups, especially when exposed to hot liquids, can release microplastics into beverages.7 Such findings raise questions about whether these so-called ‘paper-based’ alternatives are truly sustainable.
The long-term effects of micro- and nano-particles on the human body are still not fully understood, but the existing evidence paints a concerning picture. Microplastics have been detected in the human placenta8, blood9, as well as in the reproductive systems of animals10. Researchers suggest that microplastics may affect the digestive and respiratory systems, trigger inflammation and oxidative stress in tissues and organs, and contribute to endocrine disruptions, potentially impacting metabolic, developmental, and reproductive health. Several studies have also reported toxic effects at the cellular level, including physical stress and damage, necrosis, and inflammation1. Beyond human health, microplastics also have environmental implications, affecting marine and freshwater organisms and soil, eventually entering food chains that sustain all life forms.
How do we address a threat that has already entered our food, water, and even our bodies?
Plastics were invented to ease human life, but their rampant, often avoidable use poses a global challenge that calls for systemic solutions, rather than quick, superficial fixes. This includes reducing unnecessary plastic use, developing truly sustainable alternatives, revamping waste-management systems at both individual and societal levels, and strengthening regulations on how we produce, use, and discard plastic. More research is also needed to understand the long-term effects of microplastics on both human health and the environment.
Convenience has a price. Plastics have crept into all aspects of our modern lives. Perhaps the seemingly harmless dinner table question, ‘Are we having plastic for food again?’ warrants more thought.
References:
[1] Yee MS-L et al. Impact of Microplastics and Nanoplastics on Human Health. Nanomaterials. 2021; 11(2):496.
[2] Cox K.D. et al. Human Consumption of Microplastics. Environ. Sci. Technol. 2019; 53 (12), 7068-7074.
[3] Conti G.O. et al. Micro- and nano-plastics in edible fruit and vegetables. The first diet risks assessment for the general population. Environ Res. 2020; 187, 109677.
[4] Milne M.H. et al. Exposure of U.S. adults to microplastics from commonly-consumed proteins, Environ Pollution 2024; 343:123233.
[5] Qian N. et al. Rapid single-particle chemical imaging of nanoplastics by SRS microscopy. Proc. National Academy of Sciences 2024; 121(3), e2300582121.
[6] Hussain K.A. et al. Assessing the Release of Microplastics and Nanoplastics from Plastic Containers and Reusable Food Pouches: Implications for Human Health. Environ. Sci. Technol. 2023; 57(26), 9782-9792.
[7] Tianlong Z. et al. Identification and characterisation of microplastics released from plastic-coated paper cups using micro-Raman spectroscopy. Food Control 2023; 153:109901.
[8] Ragusa A. et al. Plasticenta: first evidence of microplastics in human placenta. Environ Int 2021; 146:106274
[9] Leslie et al. 2022
[10] D’Angelo S et al. Microplastics: A Threat for Male Fertility. Int J Environ Res Public Health 2021; 18(5):2392.
Author-
Dr. Mahima Sharma is a biomedical engineering research scientist whose work focuses on leveraging light-based technologies for clinical and translational applications. She completed her PhD at the Indian Institute of Technology Madras before pursuing postdoctoral research at Vanderbilt University. She is currently continuing her work at the Indian Institute of Technology Hyderabad, India, and enjoys exploring the intersection of science, storytelling, and everyday life.
Illustrator-
Vithur Varenya is an aspiring developmental biologist currently working as a Junior Research Fellow at SRMIST. Her passion for art began with observational sketching, and she especially enjoys illustrating elements of nature, often decorating her notes with creative doodles. Outside the laboratory, she spends her time exploring new subjects, experimenting with new art styles, and reading books.
